Effect of some cover crops and their secondary metabolites on nitrous oxide (N2O) emission by Pseudomonas denitrifiers isolated from chemically fertilized corn farm soil
Abstract—Using a Pseudomonas denitrifying bacterium, which had been isolated from Japanese Andisol corn farm as an active nitrous oxide (N2O) emitter and likely to be missing nosZ gene, we investigated denitrification-regulating activity of some cover crops or green manure plants against this N2O emitter. In the preliminary screening, root exudates from the 10 seedlings of yellow flowering leaf mustard (Brassica juncea) and crimson clover (Trifolium incarnatum) showed 50% repression of the N2O emission by an incomplete denitrifier Pseudomonas sp. 05CFM15-6D. When direct extracts of the seedling roots with MeOH were assayed, however, only the seedlings of B. juncea showed a remarkable inhibition of bacterial cell growth and N2O emission at concentration equivalent to 10 seedlings. The root extract from B. juncea equivalent to 2 to 4 seedlings maintained inhibiting activity toward N2O emission, while it did not affect bacterial cell growth. Conversely, water-soluble fraction from aboveground of European small radish (Raphanus sativus var. sativus) sprouts showed statistically significant acceleration of N2O emission (P<0.01) with slight but insignificant cell growth activation. As some secondary metabolites are uniquely contained in these cover crops, suppressing or accelerating activity of such phytochemicals in N2O emission was also investigated. Allyl isothiocyanate at 30 µM markedly inhibited N2O emission of the Pseudomonas denitrifier but not suppressed its cell growth. In contrast, methyl isothiocyanate sinigrin, cyanamide, and betanin did not affect on N2O emission of the denitrifier at 150-300 µM.
The IOSR Journal of Pharmacy (IOSRPHR) is an open access online & offline peer reviewed international journal, which publishes innovative research papers, reviews, mini-reviews, short communications and notes dealing with Pharmaceutical Sciences( Pharmaceutical Technology, Pharmaceutics, Biopharmaceutics, Pharmacokinetics, Pharmaceutical/Medicinal Chemistry, Computational Chemistry and Molecular Drug Design, Pharmacognosy & Phytochemistry, Pharmacology, Pharmaceutical Analysis, Pharmacy Practice, Clinical and Hospital Pharmacy, Cell Biology, Genomics and Proteomics, Pharmacogenomics, Bioinformatics and Biotechnology of Pharmaceutical Interest........more details on Aim & Scope).
All manuscripts are subject to rapid peer review. Those of high quality (not previously published and not under consideration for publication in another journal) will be published without delay.
Isolation and characterization of biosurfactants producing bacteria from oil ...Alexander Decker
This document summarizes a study that isolated and characterized bacteria from oil-polluted soil samples that can produce biosurfactants. Two bacterial species were isolated - Bacillus subtilis and Pseudomonas aeruginosa. These isolates were screened for biosurfactant production using oil displacement and blood hemolysis tests. Isolates X4 and X8 produced the largest zones of clearance, indicating greatest biosurfactant production. The biosurfactants were characterized using thin layer chromatography and were identified as rhamnolipid and surfactin. P. aeruginosa and B. subtilis were confirmed as effective producers of glycolipid and lipopeptide biosurfactants, respectively.
Effect Of Mat(Cyprus Rotundis) Industry Effluents On Biomolecules In Leaves O...iosrjce
IOSR Journal of Environmental Science, Toxicology and Food Technology (IOSR-JESTFT) multidisciplinary peer-reviewed Journal with reputable academics and experts as board member. IOSR-JESTFT is designed for the prompt publication of peer-reviewed articles in all areas of subject. The journal articles will be accessed freely online.
1) The study compared the production of biosurfactants by two bacterial strains (Strain 1 and Strain 2) using different carbon sources and concentrations.
2) The results showed that Strain 1 produced more biosurfactants than Strain 2. Dextrose as a carbon source at a concentration of 1.5% resulted in the highest biosurfactant yield for both strains.
3) Increasing the concentration of carbon sources from 0.5% to 1.5% generally increased biosurfactant production, indicating that higher concentrations favored biosurfactant production by the bacteria.
This document summarizes a study on the adsorption and kinetics of two pesticides, abamectin and imidacloprid, in greenhouse soil from Palestine. Key findings include:
1) The highest removal percentages for imidacloprid and abamectin were 13.4% and 7.5% respectively, occurring at a soil dosage of 3.0 g.
2) pH affected adsorption, with imidacloprid removal highest at pH 1.5 and lowest at pH 12, while abamectin removal was highest at pH 12 and lowest around pH 7.
3) Temperature also impacted adsorption, with binding generally increasing at higher temperatures from 15-47
Isolation and Screening for Citric Acid Production by Aspergillus Niger Using...ijtsrd
The numerous applications of citric acid have increased its demand. It is of great importance to produce citric acid using adequate monosaccharides and dissacharides as they have proven to be easily catabolyzed and decomposed by Fungi when compared to polysaccharides. The superiority of sucrose to other sugars is a result of strong extracellular mycelium bound invertase of A.niger which rapidly hydrolyses sucrose at low pH. This project was undertaken to isolate, screen and produce citric acid in a submerged fermentation by four different strains of Aspergillus niger using sucrose. Aspergillus niger was isolated and characterized from garden soil. Citric acid production from Aspergillus niger in a submerged basal medium was quantitatively determined using titrimetric method. Aspergillus niger strain HUS1 ASHUS1 , Aspergillus niger strain HUS7 ASHUS7 , Aspergillus niger strain HG49 ASHG49 and Aspergillus niger strain AN8 ASAN8 showed significant accumulation of citric acid from the submerged basal medium, of which ASHUS 1 significantly a 0.05 recorded the most yield from the production after 9 days of incubation. Mbah, O. G | Okpalla, J. O | Osuala, O. J | Okoye, P. O | Alagbu, P. O "Isolation and Screening for Citric Acid Production by Aspergillus Niger Using Sucrose as a Carbon Source" Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-5 | Issue-5 , August 2021, URL: https://www.ijtsrd.com/papers/ijtsrd46260.pdf Paper URL: https://www.ijtsrd.com/biological-science/microbiology/46260/isolation-and-screening-for-citric-acid-production-by-aspergillus-niger-using-sucrose-as-a-carbon-source/mbah-o-g
Plant growth promoting characterization of soil bacteria isolated from petrol...Agriculture Journal IJOEAR
Abstract— Contaminant-degrading bacteria can be included among the plant-growth promoting bacteria; because the presence of contaminants, in general produce negatively effects on plant’s growth; thus, the elimination of the inhibiting contaminants will benefit them. Although contaminant-degrading strains have been traditionally isolated from various environments; the number of studies that reported the isolation and identification of soil bacteria with contaminant- degrading abilities have increased. The aim of this study was to characterized microbial strains isolated from petroleum contaminated soil by plant growth promotion traits to recommend them as potential bioinoculants. In this work, five of the six soil isolates were classified as Indole Acetic Acid higher producers and only one of them as lower producer. Sporosarcina aquimarina strain -Q3 and Bacillus cereus strain +F2 tested in Axonopus affinis plantlets bioassay, showed that these isolates were the most effective promoters of this plant species; therefore, these soil bacteria with possible hydrocarbon degradation ability could be considered as potential bioinoculants and can be recommended with a practical importance for the rhizoremediation of petroleum contaminated sites and plant growth promotion.
Poly-훽-hydroxybutyrate degradation by Aspergillus fumigates isolated from soi...IOSRJPBS
Poly-β-hydroxybutyrate acid (PHB) is thermoplastic biopolymers, synthesized by some bacterial genera under stress conditions. The degradation of PHB was detected in Petri dish by formation of a clear zone around the fungal colonies due to production of depolymerase enzyme which has interesting role in PHB degradation process. The most active PHB degrader fungi was selected and identified as Aspergillus fumigates using morphological characters. The highest PHB degradation in Petri dish by A. fumigates was at pH 5, 30ᵒC and 7days. In liquid medium, degradation by A. fumigates was studied using enzyme assay method (U/ml). All the experiments were performed enzyme activities were monitored. After 3 days of incubation, maximum PHB depolymerase production was at pH 5 and 30°C. In conclusion, PHB can be degraded in solid and liquid medium using fungal depolymerase enzyme.
The IOSR Journal of Pharmacy (IOSRPHR) is an open access online & offline peer reviewed international journal, which publishes innovative research papers, reviews, mini-reviews, short communications and notes dealing with Pharmaceutical Sciences( Pharmaceutical Technology, Pharmaceutics, Biopharmaceutics, Pharmacokinetics, Pharmaceutical/Medicinal Chemistry, Computational Chemistry and Molecular Drug Design, Pharmacognosy & Phytochemistry, Pharmacology, Pharmaceutical Analysis, Pharmacy Practice, Clinical and Hospital Pharmacy, Cell Biology, Genomics and Proteomics, Pharmacogenomics, Bioinformatics and Biotechnology of Pharmaceutical Interest........more details on Aim & Scope).
All manuscripts are subject to rapid peer review. Those of high quality (not previously published and not under consideration for publication in another journal) will be published without delay.
Isolation and characterization of biosurfactants producing bacteria from oil ...Alexander Decker
This document summarizes a study that isolated and characterized bacteria from oil-polluted soil samples that can produce biosurfactants. Two bacterial species were isolated - Bacillus subtilis and Pseudomonas aeruginosa. These isolates were screened for biosurfactant production using oil displacement and blood hemolysis tests. Isolates X4 and X8 produced the largest zones of clearance, indicating greatest biosurfactant production. The biosurfactants were characterized using thin layer chromatography and were identified as rhamnolipid and surfactin. P. aeruginosa and B. subtilis were confirmed as effective producers of glycolipid and lipopeptide biosurfactants, respectively.
Effect Of Mat(Cyprus Rotundis) Industry Effluents On Biomolecules In Leaves O...iosrjce
IOSR Journal of Environmental Science, Toxicology and Food Technology (IOSR-JESTFT) multidisciplinary peer-reviewed Journal with reputable academics and experts as board member. IOSR-JESTFT is designed for the prompt publication of peer-reviewed articles in all areas of subject. The journal articles will be accessed freely online.
1) The study compared the production of biosurfactants by two bacterial strains (Strain 1 and Strain 2) using different carbon sources and concentrations.
2) The results showed that Strain 1 produced more biosurfactants than Strain 2. Dextrose as a carbon source at a concentration of 1.5% resulted in the highest biosurfactant yield for both strains.
3) Increasing the concentration of carbon sources from 0.5% to 1.5% generally increased biosurfactant production, indicating that higher concentrations favored biosurfactant production by the bacteria.
This document summarizes a study on the adsorption and kinetics of two pesticides, abamectin and imidacloprid, in greenhouse soil from Palestine. Key findings include:
1) The highest removal percentages for imidacloprid and abamectin were 13.4% and 7.5% respectively, occurring at a soil dosage of 3.0 g.
2) pH affected adsorption, with imidacloprid removal highest at pH 1.5 and lowest at pH 12, while abamectin removal was highest at pH 12 and lowest around pH 7.
3) Temperature also impacted adsorption, with binding generally increasing at higher temperatures from 15-47
Isolation and Screening for Citric Acid Production by Aspergillus Niger Using...ijtsrd
The numerous applications of citric acid have increased its demand. It is of great importance to produce citric acid using adequate monosaccharides and dissacharides as they have proven to be easily catabolyzed and decomposed by Fungi when compared to polysaccharides. The superiority of sucrose to other sugars is a result of strong extracellular mycelium bound invertase of A.niger which rapidly hydrolyses sucrose at low pH. This project was undertaken to isolate, screen and produce citric acid in a submerged fermentation by four different strains of Aspergillus niger using sucrose. Aspergillus niger was isolated and characterized from garden soil. Citric acid production from Aspergillus niger in a submerged basal medium was quantitatively determined using titrimetric method. Aspergillus niger strain HUS1 ASHUS1 , Aspergillus niger strain HUS7 ASHUS7 , Aspergillus niger strain HG49 ASHG49 and Aspergillus niger strain AN8 ASAN8 showed significant accumulation of citric acid from the submerged basal medium, of which ASHUS 1 significantly a 0.05 recorded the most yield from the production after 9 days of incubation. Mbah, O. G | Okpalla, J. O | Osuala, O. J | Okoye, P. O | Alagbu, P. O "Isolation and Screening for Citric Acid Production by Aspergillus Niger Using Sucrose as a Carbon Source" Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-5 | Issue-5 , August 2021, URL: https://www.ijtsrd.com/papers/ijtsrd46260.pdf Paper URL: https://www.ijtsrd.com/biological-science/microbiology/46260/isolation-and-screening-for-citric-acid-production-by-aspergillus-niger-using-sucrose-as-a-carbon-source/mbah-o-g
Plant growth promoting characterization of soil bacteria isolated from petrol...Agriculture Journal IJOEAR
Abstract— Contaminant-degrading bacteria can be included among the plant-growth promoting bacteria; because the presence of contaminants, in general produce negatively effects on plant’s growth; thus, the elimination of the inhibiting contaminants will benefit them. Although contaminant-degrading strains have been traditionally isolated from various environments; the number of studies that reported the isolation and identification of soil bacteria with contaminant- degrading abilities have increased. The aim of this study was to characterized microbial strains isolated from petroleum contaminated soil by plant growth promotion traits to recommend them as potential bioinoculants. In this work, five of the six soil isolates were classified as Indole Acetic Acid higher producers and only one of them as lower producer. Sporosarcina aquimarina strain -Q3 and Bacillus cereus strain +F2 tested in Axonopus affinis plantlets bioassay, showed that these isolates were the most effective promoters of this plant species; therefore, these soil bacteria with possible hydrocarbon degradation ability could be considered as potential bioinoculants and can be recommended with a practical importance for the rhizoremediation of petroleum contaminated sites and plant growth promotion.
Poly-훽-hydroxybutyrate degradation by Aspergillus fumigates isolated from soi...IOSRJPBS
Poly-β-hydroxybutyrate acid (PHB) is thermoplastic biopolymers, synthesized by some bacterial genera under stress conditions. The degradation of PHB was detected in Petri dish by formation of a clear zone around the fungal colonies due to production of depolymerase enzyme which has interesting role in PHB degradation process. The most active PHB degrader fungi was selected and identified as Aspergillus fumigates using morphological characters. The highest PHB degradation in Petri dish by A. fumigates was at pH 5, 30ᵒC and 7days. In liquid medium, degradation by A. fumigates was studied using enzyme assay method (U/ml). All the experiments were performed enzyme activities were monitored. After 3 days of incubation, maximum PHB depolymerase production was at pH 5 and 30°C. In conclusion, PHB can be degraded in solid and liquid medium using fungal depolymerase enzyme.
In a pot culture (2011), aerosols of oxidized nitrogen (NaNO2) @20kgha-1yr-1 (≈200 ppm), reduced nitrogen (NH4Cl) @10kg-1hayr-1 (≈100 ppm) and distilled water (control) were sprayed (1500 cm3plant-1) weekly at different days after sowing (DAS) to study their impacts on physiology of rice varieties (Bishnuprasad, Kanaklata, Joymati, Jyotiprasad and Mulagavaru). In a field trial (2012), the simulated N-aerosols @ 20 & 40 kg ha-1y-1 of each (1000 cm3m-2) along with a control were misted to population of the rice variety, Kanaklata at four different growth stages viz., germination and tillering (0-30 DAS), maximum tillering, (30-60 DAS), panicle initiation (60-90 DAS) and reproductive development (90-120 DAS). In both pot and field experiments, the N- aerosols brought about wide differences in net photosynthesis rates, nitrate reductase activity, nitrogen use efficiency (NUE), membrane permeability in the crop. The aerosols with lower doses at earlier growth stages influenced NUE and economic yield of the crop varieties. Mechanisms of altering membrane permeability either by depletion of Ca2+, or acceleration of peroxidase activity of cell in presence of the aerosols have been elucidated.
Antioxidant and Antimicrobial Activities Of Algerian Populus Nigra L. Buds Ex...bioejjournal
This study is part of a goal to investigate chemical composition, antibacterial, antifungal and antioxidant activities of the flower buds extracts from the Algerian Polulus nigra L., which were collected from Djarifet - mansourah at Tlemcen city in the West Northern of Algeria. In organic extracts, tanins, flavonoïds, coumarins, alkaloids and terpenoïds were the principals secondary metabolites identified from the flower buds of black poplar. Antibacterial and antifungal activities of
extracts were tested using agar-well diffusion method and micro-well determination of MIC assay against
eleven bacteria and two Candida species. It was found that extracts of black poplar buds exhibit
antibacterial and anticandidal activities with agar disk diffusion (7 to 43mm) and MIC methods (MIC=
90.33 µg/ml against several strains of bacteria and MIC=45.16 µg/ml against Candida albicans). The
antioxidant effect of hydroalcoholic extract was evaluated using DPPH and FRAP assays. It was showed good and similar activity than ascorbic acid and BHA by DPPH method: IC50= 220µg/mL for hydroethanol extract.
ANTIOXIDANT AND ANTIMICROBIAL ACTIVITIES OF ALGERIAN POPULUS NIGRA L. BUDS EX...bioejjournal
his study is part of a goal to investigate chemical composition, antibacterial, antifungal and antioxidant activities of the flower buds extracts from the Algerian Polulus nigra L., which were collected from Djarifet - mansourah at Tlemcen city in the West Northern of Algeria. In organic extracts, tanins, flavonoïds, coumarins, alkaloids and terpenoïds were the principals secondary metabolites identified from the flower buds of black poplar. Antibacterial and antifungal activities of extracts were tested using agar-well diffusion method and micro-well determination of MIC assay against eleven bacteria and two Candida species. It was found that extracts of black poplar buds exhibit antibacterial and anticandidal activities with agar disk diffusion (7 to 43mm) and MIC methods (MIC= 90.33 µg/ml against several strains of bacteria and MIC=45.16 µg/ml against Candida albicans). The antioxidant effect of hydroalcoholic extract was evaluated using DPPH and FRAP assays. It was showed good and similar activity than ascorbic acid and BHA by DPPH method: IC50= 220µg/mL for hydroethanol extract.
Analysis of Organophosphate Pesticides Residue on Crops in Abakaliki, Ebonyi ...IOSR Journals
This document analyzes organophosphate pesticide residue found on pumpkin crops in Abakaliki, Ebonyi State, Nigeria. Samples of pumpkin leaves were collected 3 days after being sprayed with organophosphate pesticides and analyzed using gas chromatography. Sample A contained dioxabenzeofos and phenanthrene. Sample B contained chlorethoxyfos, oxydeprofos, sulfotep, phenanthrene, and dioxabenzofos. Sample C contained chlonethoxy fos, oxydeprofos, sulfotep, phenanthrene, and dioxabenzofos. All residues were below the LD50 toxicity range for organophosphates. The
This document discusses a study that screened fungal rot isolates from cocoa for their ability to dissolve phosphate and grow on different media. Nine fungal rot isolates were collected from cocoa plants and tested for phosphate dissolving ability in Pikovskaya broth media using a spectrophotometer. Isolate BPB had the highest ability to dissolve phosphate, followed by isolates JT, BPG, and BPE1. The isolates were also tested for growth on three solid media - Potato Dextrose Agar, Malt Extract Agar, and Malt Peptone Agar. Malt Peptone Agar best supported the fungal mycelial growth compared to the other two media.
Production of Amphiphilic Surfactant Molecule From Saccharomyces Cerevisiae M...inventionjournals
International Journal of Pharmaceutical Science Invention (IJPSI) is an international journal intended for professionals and researchers in all fields of Pahrmaceutical Science. IJPSI publishes research articles and reviews within the whole field Pharmacy and Pharmaceutical Science, new teaching methods, assessment, validation and the impact of new technologies and it will continue to provide information on the latest trends and developments in this ever-expanding subject. The publications of papers are selected through double peer reviewed to ensure originality, relevance, and readability. The articles published in our journal can be accessed online.
This study isolated 10 bacterial isolates from oil-contaminated soil in Hilla City, Iraq that were able to degrade crude oil. 9 isolates were identified as Pseudomonas aeruginosa and 1 as Bacillus spp. All isolates were screened for biosurfactant production using hemolytic activity, emulsification index, lipolytic activity, and oil displacement assays. Most isolates showed biosurfactant activity. PCR was used to detect genes for phenol monooxygenase and xylene monooxygenase. 2 P. aeruginosa isolates tested positive for the phenol monooxygenase gene. This study concluded the isolates have potential to degrade crude oil and produce biosurfactants.
The pilot study on Ibuprofen uptake by carrotiosrjce
IOSR Journal of Environmental Science, Toxicology and Food Technology (IOSR-JESTFT) multidisciplinary peer-reviewed Journal with reputable academics and experts as board member. IOSR-JESTFT is designed for the prompt publication of peer-reviewed articles in all areas of subject. The journal articles will be accessed freely online
This document summarizes a study that isolated and characterized bacteria with the ability to oxidize sulfur and magnesium from soil samples. Specifically:
- Bacillus sp. and Serratia marcescens were found to efficiently oxidize sulfur and magnesium, respectively, as determined by biochemical and 16S rDNA sequencing analysis.
- Biofertilizers containing these isolates significantly enhanced plant growth and nutrient uptake in greenhouse studies when compared to untreated controls.
- The study demonstrates the potential of these bacteria to solubilize important secondary nutrients like sulfur and magnesium and improve soil fertility.
EDTA-enhanced phytoextraction of Cd and Pb in spiked soil with Marigold and a...Agriculture Journal IJOEAR
Abstract— EDTA is a common chelating agent used in phytoextraction for enhancing the trace elements uptake from soil to plants. But application of EDTA can cause ground water contamination, which is potentially a risk for human health. In this study EDTA-enhanced phytoextraction of Cd and Pb by Marigold. was evaluated. Application of EDTA could significantly increase Cd and Pb accumulation in the various part of plants, but EDTA addition also increased the Cd and Pb concentration in leached water about 8 to 12 time and 50 to 75 times respectively compared to the control. So, insitu application of EDTA can be potentially risk to ground water contamination with trace elements.
Biodegradation of dichlorovos (organophosphate pesticide) in soil by bacteria...Alexander Decker
This document summarizes a study that investigated the potential for microbial isolates to biodegrade the organophosphate pesticide dichlorvos in contaminated agricultural soil. A bacterial consortium composed of four strains (Proteus vulgaris, Vibrio sp., Serratia sp., and Acinetobacter sp.) was isolated from soil contaminated with dichlorvos. Both the consortium and individual strains were able to use dichlorvos as their sole carbon source and remove it from the soil. The consortium achieved greater removal of dichlorvos from soil amended with NPK fertilizer compared to NH4NO3 or KH2PO4. The results indicate that these bacterial isolates have potential for bioremediating soils contaminated
PRODUCTION AND CHARACTERIZATION OF BIOSURFACTANTS PRODUCED BY Pseudomonas aer...UniversitasGadjahMada
The biosurfactants are used by several industrial sectors such as petroleum, agriculture, food production, chemistry, cosmetics, and pharmaceuticals. Because of their hydrophobic and hydrophilic moieties, they have potency to reduce surface tension, interfacial tension between water-hydrocarbon systems, and low micelle concentration. Their characteristics strongly depend on the producer strain as well as on the medium composition, such as carbon and nitrogen sources. This study was conducted to investigate the influence of different sources of carbon (n-hexadecane, glycerol and glucose) and nitrogen (urea, NH4Cl and NaNO3 ) for the production of biosurfactants by a new strain of Pseudomonas aeruginosa B031 isolated from a rhizosphere of Paraserianthes falcataria L. Nielsen, a hardwood plant species at a phytoremediation field. The biosurfactant characteristics of the strain were evaluated, particularly its surface-active properties and potential to remove hydrocarbon. Glycerol was found to be the optimum carbon source, with rhamnose concentration, emulsification index, and critical micelle concentration (CMC) of 718 mg/L, 37%, and 35 mN/m, respectively. Sodium nitrate (NaNO3 ) was observed as the optimum nitrogen source, with rhamnose concentration, emulsification index, and CMC of 290 mg/L, 30%, and 24 mN/m, respectively. These biosurfactants efficiently reduced surface tension of culture broth from 42 mN/m to 31 mN/m for the glycerol treatment and from 37 mN/m to 24 mN/m for the sodium nitrate treatment. The crude biosurfactants from the glycerol and sodium nitrate treatments also removed 87.5% and 84%, respectively, of crude oil from sand. These rates were higher than those of the chemical surfactants (SDS and Triton X-100). These findings indicate that the biosurfactants produced by the strain from both glycerol and NaNO3 treatments can efficiently decrease the interfacial tension of culture broth dilution and have a high emulsion index, thus hold promise in hydrocarbon bioremediation application.
Phytochemical Comparative Screening of Aqueous Extracts of the Leaves, Stem b...iosrjce
IOSR Journal of Biotechnology and Biochemistry (IOSR-JBB) covers studies of the chemical processes in living organisms, structure and function of cellular components such as proteins, carbohydrates, lipids, nucleic acids and other biomolecules, chemical properties of important biological molecules, like proteins, in particular the chemistry of enzyme-catalyzed reactions, genetic code (DNA, RNA), protein synthesis, cell membrane transport, and signal transduction. IOSR-JBB is privileged to focus on a wide range of biotechnology as well as high quality articles on genetic engineering, cell and tissue culture technologies, genetics, microbiology, molecular biology, biochemistry, embryology, cell biology, chemical engineering, bioprocess engineering, information technology, biorobotics.
Phosphate and nitrate removal from aqueous solution by carbonated and uncarbo...Alexander Decker
This study investigated the potential for using Monodora myristica shell to remove phosphate and nitrate from wastewater. Four types of shells were tested: untreated raw, treated raw, untreated carbonated, and treated carbonated. The shells were added to solutions containing phosphate and nitrate at concentrations of 2.5%, 5%, and 10%. The solutions were tested over 5 hours. The results showed the shells had no ability to remove phosphate. However, they were effective at removing nitrate, with the untreated carbonated shell achieving the greatest reduction from 231 mg/L to 28.57 mg/L using 10% shell concentration after 3 hours. In general, higher shell concentrations produced better nitrate removal.
Mineralization Of Diesel-Base Engine Oil By Fungi Isolated From Selected Work...inventionjournals
International Journal of Pharmaceutical Science Invention (IJPSI) is an international journal intended for professionals and researchers in all fields of Pahrmaceutical Science. IJPSI publishes research articles and reviews within the whole field Pharmacy and Pharmaceutical Science, new teaching methods, assessment, validation and the impact of new technologies and it will continue to provide information on the latest trends and developments in this ever-expanding subject. The publications of papers are selected through double peer reviewed to ensure originality, relevance, and readability. The articles published in our journal can be accessed online.
Biologically active saponin from seeds of allium ampeloprasumAlexander Decker
This document describes research into isolating and characterizing a biologically active saponin compound from the seeds of Allium ampeloprasum (wild leek). Through a series of extraction and purification steps including column chromatography, the researchers isolated a novel oleanen-type triterpenoid glycoside. Spectroscopic analysis including NMR, IR, MS and acid hydrolysis revealed the compound's structure as a pentaglycoside consisting of glucose, xylose, and rhamnose sugars attached to an oleanolic acid sapogenin core. Testing showed the isolated saponin had significant antimicrobial activity against bacteria and fungi. This is the first report of this saponin's isolation, structure determination, and
Effect of Temperature and Moisture on Degradation of Herbicide Atrazine in Ag...Agriculture Journal IJOEAR
Abstract— Degradation rate and degraded products, deethylatrazine (DEA), deisopropylatrazine (DIA) and atrazine-2-hydroxy (HA), of herbicide atrazine in agricultural soil were determined by ultra-performance liquid chromatography–mass spectrometry. When treating soils for 60d at 25°C, the degradation rate of atrazine increased with the moisture from 5 to 20%. The degradation was fitted one-order kinetic equation and degradation rate constant (k) and Half-life (T1/2) were obtained. T1/2 decreased by 3–4 folds with the increasing temperature from 5 to 35°C and moisture from 5 to 20%. The species and content of the degraded products increased with the temperature and moisture. When treating soil for 60d, the sum content of three degraded products, DEA, DIA and HA is 3–6.8 times greater than atrazine residue. An updated metabolism pathway of atrazine in soil was presented.
This document summarizes a study that used a continuous stirred bed reactor (SBR) to treat textile wastewater through bacterial decolourisation. A mixture of three bacterial strains - Sphingomonas paucimobilis, Bacillus sp., and filamentous bacteria - were introduced to the SBR. The study used a mixture experimental design to optimize the formulation of bacterial strains and assess colour and COD removal. The results found that the highest predictable decolourisation and COD removal rates were 86.72% and 75.06% respectively. Regression analysis showed excellent correlation between the bacterial mixtures and responses of decolourisation and COD removal.
This document discusses soil microbiology and the nitrogen cycle. It begins by explaining that soil contains hundreds of millions to billions of microbes per gram, with bacteria being the most numerous. The growth and activities of soil microbes are controlled by factors like organic carbon, moisture, aeration, pH, temperature, and nutrients. Soil microbes play important roles in soil structure, converting nutrients into plant-available forms, and directly and indirectly promoting plant growth. The nitrogen cycle is then described, including the key processes of nitrogen fixation, nitrification, denitrification, and anammox that transform nitrogen between its different chemical forms and maintain the environment.
The document provides an overview of a training manual for using school gardens as outdoor classrooms. It was developed by the US Department of Agriculture and partners to support academic and food security needs in several African countries. The training manual and accompanying toolkit are meant to train others to teach students using school garden activities integrated into various subjects. The toolkit includes materials like lesson plans, guides, and visual aids available for free online use. The training manual then provides guidance for using participatory teaching methods and the various toolkit materials to train teachers to utilize the school garden approach.
The nitrogen cycle is the biogeochemical cycle by which nitrogen is converted into various chemical forms as it circulates among the atmosphere and terrestrial and marine ecosystems. The conversion of nitrogen can be carried out through both biological and physical processes. Important processes in the nitrogen cycle include fixation, ammonification, nitrification, and denitrification. The majority of Earth's atmosphere (78%) is nitrogen, making it the largest pool of nitrogen. However, atmospheric nitrogen has limited availability for biological use, leading to a scarcity of usable nitrogen in many types of ecosystems. The nitrogen cycle is of particular interest to ecologists because nitrogen availability can affect the rate of key ecosystem processes, including primary production and decomposition. Human activities such as fossil fuel combustion, use of artificial nitrogen fertilizers, and release of nitrogen in wastewater have dramatically altered the global nitrogen cycle.
The document discusses the nitrogen cycle, which is the process by which nitrogen is converted between various chemical forms through biological and non-biological processes. It outlines several key microbial nitrogen transformations: nitrogen fixation by bacteria converts atmospheric nitrogen to ammonia; nitrification converts ammonia to nitrites and nitrates; denitrification converts nitrates back to nitrogen gas; and anammox converts nitrites and ammonium directly to nitrogen gas. It also discusses the enzymes, genes and electrons involved in these transformations, as well as deficiency symptoms from a lack of fixed nitrogen.
In a pot culture (2011), aerosols of oxidized nitrogen (NaNO2) @20kgha-1yr-1 (≈200 ppm), reduced nitrogen (NH4Cl) @10kg-1hayr-1 (≈100 ppm) and distilled water (control) were sprayed (1500 cm3plant-1) weekly at different days after sowing (DAS) to study their impacts on physiology of rice varieties (Bishnuprasad, Kanaklata, Joymati, Jyotiprasad and Mulagavaru). In a field trial (2012), the simulated N-aerosols @ 20 & 40 kg ha-1y-1 of each (1000 cm3m-2) along with a control were misted to population of the rice variety, Kanaklata at four different growth stages viz., germination and tillering (0-30 DAS), maximum tillering, (30-60 DAS), panicle initiation (60-90 DAS) and reproductive development (90-120 DAS). In both pot and field experiments, the N- aerosols brought about wide differences in net photosynthesis rates, nitrate reductase activity, nitrogen use efficiency (NUE), membrane permeability in the crop. The aerosols with lower doses at earlier growth stages influenced NUE and economic yield of the crop varieties. Mechanisms of altering membrane permeability either by depletion of Ca2+, or acceleration of peroxidase activity of cell in presence of the aerosols have been elucidated.
Antioxidant and Antimicrobial Activities Of Algerian Populus Nigra L. Buds Ex...bioejjournal
This study is part of a goal to investigate chemical composition, antibacterial, antifungal and antioxidant activities of the flower buds extracts from the Algerian Polulus nigra L., which were collected from Djarifet - mansourah at Tlemcen city in the West Northern of Algeria. In organic extracts, tanins, flavonoïds, coumarins, alkaloids and terpenoïds were the principals secondary metabolites identified from the flower buds of black poplar. Antibacterial and antifungal activities of
extracts were tested using agar-well diffusion method and micro-well determination of MIC assay against
eleven bacteria and two Candida species. It was found that extracts of black poplar buds exhibit
antibacterial and anticandidal activities with agar disk diffusion (7 to 43mm) and MIC methods (MIC=
90.33 µg/ml against several strains of bacteria and MIC=45.16 µg/ml against Candida albicans). The
antioxidant effect of hydroalcoholic extract was evaluated using DPPH and FRAP assays. It was showed good and similar activity than ascorbic acid and BHA by DPPH method: IC50= 220µg/mL for hydroethanol extract.
ANTIOXIDANT AND ANTIMICROBIAL ACTIVITIES OF ALGERIAN POPULUS NIGRA L. BUDS EX...bioejjournal
his study is part of a goal to investigate chemical composition, antibacterial, antifungal and antioxidant activities of the flower buds extracts from the Algerian Polulus nigra L., which were collected from Djarifet - mansourah at Tlemcen city in the West Northern of Algeria. In organic extracts, tanins, flavonoïds, coumarins, alkaloids and terpenoïds were the principals secondary metabolites identified from the flower buds of black poplar. Antibacterial and antifungal activities of extracts were tested using agar-well diffusion method and micro-well determination of MIC assay against eleven bacteria and two Candida species. It was found that extracts of black poplar buds exhibit antibacterial and anticandidal activities with agar disk diffusion (7 to 43mm) and MIC methods (MIC= 90.33 µg/ml against several strains of bacteria and MIC=45.16 µg/ml against Candida albicans). The antioxidant effect of hydroalcoholic extract was evaluated using DPPH and FRAP assays. It was showed good and similar activity than ascorbic acid and BHA by DPPH method: IC50= 220µg/mL for hydroethanol extract.
Analysis of Organophosphate Pesticides Residue on Crops in Abakaliki, Ebonyi ...IOSR Journals
This document analyzes organophosphate pesticide residue found on pumpkin crops in Abakaliki, Ebonyi State, Nigeria. Samples of pumpkin leaves were collected 3 days after being sprayed with organophosphate pesticides and analyzed using gas chromatography. Sample A contained dioxabenzeofos and phenanthrene. Sample B contained chlorethoxyfos, oxydeprofos, sulfotep, phenanthrene, and dioxabenzofos. Sample C contained chlonethoxy fos, oxydeprofos, sulfotep, phenanthrene, and dioxabenzofos. All residues were below the LD50 toxicity range for organophosphates. The
This document discusses a study that screened fungal rot isolates from cocoa for their ability to dissolve phosphate and grow on different media. Nine fungal rot isolates were collected from cocoa plants and tested for phosphate dissolving ability in Pikovskaya broth media using a spectrophotometer. Isolate BPB had the highest ability to dissolve phosphate, followed by isolates JT, BPG, and BPE1. The isolates were also tested for growth on three solid media - Potato Dextrose Agar, Malt Extract Agar, and Malt Peptone Agar. Malt Peptone Agar best supported the fungal mycelial growth compared to the other two media.
Production of Amphiphilic Surfactant Molecule From Saccharomyces Cerevisiae M...inventionjournals
International Journal of Pharmaceutical Science Invention (IJPSI) is an international journal intended for professionals and researchers in all fields of Pahrmaceutical Science. IJPSI publishes research articles and reviews within the whole field Pharmacy and Pharmaceutical Science, new teaching methods, assessment, validation and the impact of new technologies and it will continue to provide information on the latest trends and developments in this ever-expanding subject. The publications of papers are selected through double peer reviewed to ensure originality, relevance, and readability. The articles published in our journal can be accessed online.
This study isolated 10 bacterial isolates from oil-contaminated soil in Hilla City, Iraq that were able to degrade crude oil. 9 isolates were identified as Pseudomonas aeruginosa and 1 as Bacillus spp. All isolates were screened for biosurfactant production using hemolytic activity, emulsification index, lipolytic activity, and oil displacement assays. Most isolates showed biosurfactant activity. PCR was used to detect genes for phenol monooxygenase and xylene monooxygenase. 2 P. aeruginosa isolates tested positive for the phenol monooxygenase gene. This study concluded the isolates have potential to degrade crude oil and produce biosurfactants.
The pilot study on Ibuprofen uptake by carrotiosrjce
IOSR Journal of Environmental Science, Toxicology and Food Technology (IOSR-JESTFT) multidisciplinary peer-reviewed Journal with reputable academics and experts as board member. IOSR-JESTFT is designed for the prompt publication of peer-reviewed articles in all areas of subject. The journal articles will be accessed freely online
This document summarizes a study that isolated and characterized bacteria with the ability to oxidize sulfur and magnesium from soil samples. Specifically:
- Bacillus sp. and Serratia marcescens were found to efficiently oxidize sulfur and magnesium, respectively, as determined by biochemical and 16S rDNA sequencing analysis.
- Biofertilizers containing these isolates significantly enhanced plant growth and nutrient uptake in greenhouse studies when compared to untreated controls.
- The study demonstrates the potential of these bacteria to solubilize important secondary nutrients like sulfur and magnesium and improve soil fertility.
EDTA-enhanced phytoextraction of Cd and Pb in spiked soil with Marigold and a...Agriculture Journal IJOEAR
Abstract— EDTA is a common chelating agent used in phytoextraction for enhancing the trace elements uptake from soil to plants. But application of EDTA can cause ground water contamination, which is potentially a risk for human health. In this study EDTA-enhanced phytoextraction of Cd and Pb by Marigold. was evaluated. Application of EDTA could significantly increase Cd and Pb accumulation in the various part of plants, but EDTA addition also increased the Cd and Pb concentration in leached water about 8 to 12 time and 50 to 75 times respectively compared to the control. So, insitu application of EDTA can be potentially risk to ground water contamination with trace elements.
Biodegradation of dichlorovos (organophosphate pesticide) in soil by bacteria...Alexander Decker
This document summarizes a study that investigated the potential for microbial isolates to biodegrade the organophosphate pesticide dichlorvos in contaminated agricultural soil. A bacterial consortium composed of four strains (Proteus vulgaris, Vibrio sp., Serratia sp., and Acinetobacter sp.) was isolated from soil contaminated with dichlorvos. Both the consortium and individual strains were able to use dichlorvos as their sole carbon source and remove it from the soil. The consortium achieved greater removal of dichlorvos from soil amended with NPK fertilizer compared to NH4NO3 or KH2PO4. The results indicate that these bacterial isolates have potential for bioremediating soils contaminated
PRODUCTION AND CHARACTERIZATION OF BIOSURFACTANTS PRODUCED BY Pseudomonas aer...UniversitasGadjahMada
The biosurfactants are used by several industrial sectors such as petroleum, agriculture, food production, chemistry, cosmetics, and pharmaceuticals. Because of their hydrophobic and hydrophilic moieties, they have potency to reduce surface tension, interfacial tension between water-hydrocarbon systems, and low micelle concentration. Their characteristics strongly depend on the producer strain as well as on the medium composition, such as carbon and nitrogen sources. This study was conducted to investigate the influence of different sources of carbon (n-hexadecane, glycerol and glucose) and nitrogen (urea, NH4Cl and NaNO3 ) for the production of biosurfactants by a new strain of Pseudomonas aeruginosa B031 isolated from a rhizosphere of Paraserianthes falcataria L. Nielsen, a hardwood plant species at a phytoremediation field. The biosurfactant characteristics of the strain were evaluated, particularly its surface-active properties and potential to remove hydrocarbon. Glycerol was found to be the optimum carbon source, with rhamnose concentration, emulsification index, and critical micelle concentration (CMC) of 718 mg/L, 37%, and 35 mN/m, respectively. Sodium nitrate (NaNO3 ) was observed as the optimum nitrogen source, with rhamnose concentration, emulsification index, and CMC of 290 mg/L, 30%, and 24 mN/m, respectively. These biosurfactants efficiently reduced surface tension of culture broth from 42 mN/m to 31 mN/m for the glycerol treatment and from 37 mN/m to 24 mN/m for the sodium nitrate treatment. The crude biosurfactants from the glycerol and sodium nitrate treatments also removed 87.5% and 84%, respectively, of crude oil from sand. These rates were higher than those of the chemical surfactants (SDS and Triton X-100). These findings indicate that the biosurfactants produced by the strain from both glycerol and NaNO3 treatments can efficiently decrease the interfacial tension of culture broth dilution and have a high emulsion index, thus hold promise in hydrocarbon bioremediation application.
Phytochemical Comparative Screening of Aqueous Extracts of the Leaves, Stem b...iosrjce
IOSR Journal of Biotechnology and Biochemistry (IOSR-JBB) covers studies of the chemical processes in living organisms, structure and function of cellular components such as proteins, carbohydrates, lipids, nucleic acids and other biomolecules, chemical properties of important biological molecules, like proteins, in particular the chemistry of enzyme-catalyzed reactions, genetic code (DNA, RNA), protein synthesis, cell membrane transport, and signal transduction. IOSR-JBB is privileged to focus on a wide range of biotechnology as well as high quality articles on genetic engineering, cell and tissue culture technologies, genetics, microbiology, molecular biology, biochemistry, embryology, cell biology, chemical engineering, bioprocess engineering, information technology, biorobotics.
Phosphate and nitrate removal from aqueous solution by carbonated and uncarbo...Alexander Decker
This study investigated the potential for using Monodora myristica shell to remove phosphate and nitrate from wastewater. Four types of shells were tested: untreated raw, treated raw, untreated carbonated, and treated carbonated. The shells were added to solutions containing phosphate and nitrate at concentrations of 2.5%, 5%, and 10%. The solutions were tested over 5 hours. The results showed the shells had no ability to remove phosphate. However, they were effective at removing nitrate, with the untreated carbonated shell achieving the greatest reduction from 231 mg/L to 28.57 mg/L using 10% shell concentration after 3 hours. In general, higher shell concentrations produced better nitrate removal.
Mineralization Of Diesel-Base Engine Oil By Fungi Isolated From Selected Work...inventionjournals
International Journal of Pharmaceutical Science Invention (IJPSI) is an international journal intended for professionals and researchers in all fields of Pahrmaceutical Science. IJPSI publishes research articles and reviews within the whole field Pharmacy and Pharmaceutical Science, new teaching methods, assessment, validation and the impact of new technologies and it will continue to provide information on the latest trends and developments in this ever-expanding subject. The publications of papers are selected through double peer reviewed to ensure originality, relevance, and readability. The articles published in our journal can be accessed online.
Biologically active saponin from seeds of allium ampeloprasumAlexander Decker
This document describes research into isolating and characterizing a biologically active saponin compound from the seeds of Allium ampeloprasum (wild leek). Through a series of extraction and purification steps including column chromatography, the researchers isolated a novel oleanen-type triterpenoid glycoside. Spectroscopic analysis including NMR, IR, MS and acid hydrolysis revealed the compound's structure as a pentaglycoside consisting of glucose, xylose, and rhamnose sugars attached to an oleanolic acid sapogenin core. Testing showed the isolated saponin had significant antimicrobial activity against bacteria and fungi. This is the first report of this saponin's isolation, structure determination, and
Effect of Temperature and Moisture on Degradation of Herbicide Atrazine in Ag...Agriculture Journal IJOEAR
Abstract— Degradation rate and degraded products, deethylatrazine (DEA), deisopropylatrazine (DIA) and atrazine-2-hydroxy (HA), of herbicide atrazine in agricultural soil were determined by ultra-performance liquid chromatography–mass spectrometry. When treating soils for 60d at 25°C, the degradation rate of atrazine increased with the moisture from 5 to 20%. The degradation was fitted one-order kinetic equation and degradation rate constant (k) and Half-life (T1/2) were obtained. T1/2 decreased by 3–4 folds with the increasing temperature from 5 to 35°C and moisture from 5 to 20%. The species and content of the degraded products increased with the temperature and moisture. When treating soil for 60d, the sum content of three degraded products, DEA, DIA and HA is 3–6.8 times greater than atrazine residue. An updated metabolism pathway of atrazine in soil was presented.
This document summarizes a study that used a continuous stirred bed reactor (SBR) to treat textile wastewater through bacterial decolourisation. A mixture of three bacterial strains - Sphingomonas paucimobilis, Bacillus sp., and filamentous bacteria - were introduced to the SBR. The study used a mixture experimental design to optimize the formulation of bacterial strains and assess colour and COD removal. The results found that the highest predictable decolourisation and COD removal rates were 86.72% and 75.06% respectively. Regression analysis showed excellent correlation between the bacterial mixtures and responses of decolourisation and COD removal.
This document discusses soil microbiology and the nitrogen cycle. It begins by explaining that soil contains hundreds of millions to billions of microbes per gram, with bacteria being the most numerous. The growth and activities of soil microbes are controlled by factors like organic carbon, moisture, aeration, pH, temperature, and nutrients. Soil microbes play important roles in soil structure, converting nutrients into plant-available forms, and directly and indirectly promoting plant growth. The nitrogen cycle is then described, including the key processes of nitrogen fixation, nitrification, denitrification, and anammox that transform nitrogen between its different chemical forms and maintain the environment.
The document provides an overview of a training manual for using school gardens as outdoor classrooms. It was developed by the US Department of Agriculture and partners to support academic and food security needs in several African countries. The training manual and accompanying toolkit are meant to train others to teach students using school garden activities integrated into various subjects. The toolkit includes materials like lesson plans, guides, and visual aids available for free online use. The training manual then provides guidance for using participatory teaching methods and the various toolkit materials to train teachers to utilize the school garden approach.
The nitrogen cycle is the biogeochemical cycle by which nitrogen is converted into various chemical forms as it circulates among the atmosphere and terrestrial and marine ecosystems. The conversion of nitrogen can be carried out through both biological and physical processes. Important processes in the nitrogen cycle include fixation, ammonification, nitrification, and denitrification. The majority of Earth's atmosphere (78%) is nitrogen, making it the largest pool of nitrogen. However, atmospheric nitrogen has limited availability for biological use, leading to a scarcity of usable nitrogen in many types of ecosystems. The nitrogen cycle is of particular interest to ecologists because nitrogen availability can affect the rate of key ecosystem processes, including primary production and decomposition. Human activities such as fossil fuel combustion, use of artificial nitrogen fertilizers, and release of nitrogen in wastewater have dramatically altered the global nitrogen cycle.
The document discusses the nitrogen cycle, which is the process by which nitrogen is converted between various chemical forms through biological and non-biological processes. It outlines several key microbial nitrogen transformations: nitrogen fixation by bacteria converts atmospheric nitrogen to ammonia; nitrification converts ammonia to nitrites and nitrates; denitrification converts nitrates back to nitrogen gas; and anammox converts nitrites and ammonium directly to nitrogen gas. It also discusses the enzymes, genes and electrons involved in these transformations, as well as deficiency symptoms from a lack of fixed nitrogen.
This document provides guidance for teachers on teaching the Exploratory Course on Agricultural Crop Production under the K to 12 Technology and Livelihood Education (TLE) curriculum. It outlines the overall goal of developing 21st century skills in students. TLE aims to develop technological proficiency through knowledge, entrepreneurship concepts, and work values. The 24 TLE exploratory courses focus on basic competencies and each has a learning module consisting of 4-5 lessons. The courses are designed based on Technical Education Skills and Development Authority (TESDA) Training Regulations to help students earn certificates and qualify for lucrative jobs.
This document defines various agricultural terms and tools. It describes farm equipment as machinery used for crop production and land preparation, while farm implements are accessories pulled by animals or farm vehicles. Farm tools are lighter objects used without animals or machinery. Various common hand tools are then listed and described, including hoes, rakes, shovels, and pruning shears. The document also provides examples of farm implements like plows and harrows, as well as farm equipment like tractors. It discusses farm inputs, labor, and basic calculations in agriculture.
Here are the answers to your questions:
1. What is an equipment? (4 points)
An equipment refers to tools, instruments, devices, and machinery used in agricultural crop production operations that require more power than hand tools. They are usually motorized or animal-drawn. (4 points)
2. Give the specific uses and function of the following equipment:
A. Hand tractor (3 points)
A hand tractor is a small tractor powered by a gasoline engine and used for tilling small areas of land. Its functions include plowing, harrowing, and transporting farm inputs and outputs. (3 points)
B. Four wheel tractor (3 points)
A four wheel tractor is a
The document summarizes the nitrogen cycle, which is a process by which nitrogen is converted between its various chemical forms and circulated among air, land, water, and living organisms. Nitrogen is essential for all life and comprises 70-71% of the atmosphere. It enters organisms through eating, drinking, and breathing and is converted to forms such as ammonium, nitrates, and urea that can be used by plants and animals. The nitrogen cycle is linked to the water cycle as nitrogen is absorbed by plants from the soil and returns to the atmosphere.
1. The nitrogen cycle describes how nitrogen is converted between its various forms and moves between the atmosphere, soil, plants, and animals.
2. Atmospheric nitrogen is converted to ammonia or nitrates through nitrogen fixation, which allows plants and animals to use it.
3. Nitrification and ammonification convert ammonia into other nitrogen forms that plants can use, and denitrification returns nitrogen to the atmosphere, completing the cycle.
Similar to Effect of some cover crops and their secondary metabolites on nitrous oxide (N2O) emission by Pseudomonas denitrifiers isolated from chemically fertilized corn farm soil
ABSTRACT- Tagetes erecta L. was raised in pots containing soil treated with various concentrations of Pb(NO3)2 (500, 1000, 1500, 2000 and 2500mg/kg). At maturity plants were separated into root, stem, leaves and inflorescence and lead accumulated in each part was quantified. The effects of lead accumulation on growth was analyzed by the measurement of various growth parameters like root and shoot length, fresh and dry weight of root and shoot and total leaf area per plant. Moreover effect of lead accumulation on biochemical parameters was checked by quantitative estimation of various biochemical parameters like chlorophyll, total protein, free amino acids, total sugar, reducing sugar and starch. Results showed that there is no remarkable negative effect of accumulation of lead on the morphological growth of the plant. Biochemical analysis showed that amount of total protein continuously decreased whereas that of free amino acids continuously increased with increasing concentrations of lead. Amount of chlorophyll, total sugar, reducing sugar and starch contents continuously increased till mid-level i.e., Pb 1500 mg/kg and then continuously decreased at higher concentrations. Results of quantitative estimation of Pb in root, stem, leaves and inflorescence showed that roots accumulated highest amount of Pb followed by stem and leaves, whereas inflorescence contained least amount of Pb.
Key-words- Lead (Pb), Heavy metal, Tagetes erecta L., Accumulation, Phytoremediation
Influence of carbon and nitrogen sources on the spore yield of Trichoderma ha...Open Access Research Paper
The influence of carbon and nitrogen sources on the spore yield of T. harzianum in fed-batch culture was investigated. T. harzianum was cultivated in liquid culture media under the effect of different carbon and nitrogen sources at different concentration using a fed-batch process. It was observed that among the various carbon sources studied, glucose (2.5 g l-1) gave the highest spore yield of 2.81±0.14 while starch (15.0 g l-1) gave the lowest spore yield (0.22±0.17). The effect of nitrogen sources revealed that 1.0 g l-1 of casein enhanced the highest spore yield (2.88±0.02) while the lowest spore yield (0.23±0.02) was recorded in medium containing soy meal (9.0 g l-1) preparation. The results revealed that T. harzianum has the ability to utilize various carbon and nitrogen compounds and produce high spore yield at low carbon and nitrogen concentration. This can be considered during industrial production of T. harzianum spores for biocontrol.
Kasahun's presentation on garlic tissue cultureAmare Kassahun
The document summarizes experiments conducted to optimize a protocol for in vitro propagation of garlic (Allium sativum L.) variety Tseday 92 using basal plate culture. Key findings include:
1) The highest shoot initiation percentage (86.66%) was achieved on medium supplemented with 0.5 or 1.5 mg/L BAP.
2) The maximum number of shoots per explant (9 shoots) was obtained from medium with 1 mg/L BAP and 0.5 mg/L NAA.
3) The highest rooting percentage (100%) and number of roots per explant (10.67) was achieved on medium with 0.5 mg/L NAA.
This document discusses green synthesis methods for producing different types of nanoparticles. It describes using plant extracts, honey, and microorganisms to synthesize silver, gold, zinc oxide, and cadmium sulfide nanoparticles. The green synthesis methods are environmentally friendly and cost effective alternatives to traditional chemical production techniques. Some key advantages of green synthesis include using natural reducing and capping agents, operating at ambient temperatures and pressures, and producing nanoparticles with applications in areas like dentistry, water purification, and environmental remediation.
In order to clean up soils contaminated with hydrocarbons, the bioremediation activity of Pseudomonas putida was studied. Pseudomonas putida is a bacterium that can withstand the harshest environmental conditions. It is able to metabolize a wide range of petroleum hydrocarbons which is used as a source of carbon and energy. Given the potential of this microorganism, an experiment wasconducted on this strain.
For the isolation of this microorganism, a sample ofsoil from the Vakinankaratra region in the urban commune of Antsirabe II, Madagascar was microbiologically analysed. The bacterial identification was based on a study of the morphological, physicochemical and sequential analysis of the 16S rDNA gene.
Use of stable and radio isotopes to understand the plant physiological processRAHUL GOPALE
Introduction
what is isotope ?
Types of Isotopes
Isotopic Labelling
ADVANTAGES AND DISADVANTAGES OF ISOTOPIC STUDY
APPLICATIONS OF ISOTOPES IN AGRICULTURE
Principle isotopes used in plant-soil studies
Case studies
FUTURE THRUSTS OF ISOTOPIC STUDY
CONCLUSIONS
REFERENCES
Response of aquatic fern(Azolla), to watercontaminationKavitha Cingam
The document summarizes a study on the response of the aquatic fern Azolla to contamination by the antibiotic ciprofloxacin (Cipro). The study investigated Azolla's ability to uptake Cipro and the effects on its nitrogen-fixing process. The results showed that Azolla is able to uptake concentrations of Cipro above levels that classify plants as hyperaccumulators. Exposure to Cipro negatively impacted the heterocyst/vegetative cell ratio, nitrogenase activity, total nitrogen, and disrupted photosynthesis. This suggests that Cipro is toxic not only to the nitrogen-fixing cyanobacteria in Azolla but also to Azolla itself, demonstrating its potential use in phytoremediation of Cipro contamination
1. The document describes an experiment to standardize the in vitro regeneration of sugarcane (Saccharum officinarum L.) through micropropagation.
2. Various explants, sterilization techniques, growth hormone concentrations, and media formulations were tested to optimize shoot initiation, multiplication, rooting, and hardening of sugarcane plantlets.
3. The most successful protocol involved sterilization with sodium hypochlorite and mercuric chloride, followed by culture of nodal segments and meristems on shoot initiation medium supplemented with 2-3 mg/L BAP and 1-1.5 mg/L kinetin for shooting, and rooting medium with NAA for development of roots
1) The study examined the effect of chemical composition of plant residues on nitrogen mineralization in soil. 2) It found that plant residues with high nitrogen and low lignin and polyphenol concentrations mineralized nitrogen rapidly, while residues with low nitrogen immobilized nitrogen for long periods. 3) The percentage of nitrogen mineralized from residues was strongly correlated with the nitrogen concentration and other quality parameters involving nitrogen concentration such as C:N ratio.
Treatment of Sewage by Phytoremediation method using Izndian mustard Plantijtsrd
Increasing urbanization, industrialization and over population is one of the leading causes of environmental degradation and pollution. Aquatic bodies are the traditional recipients of sewage containing heavy contaminants, which are released in higher concentrations and cause deleterious effects on organisms. Phytoremediation, an ecofriendly technology which is both ecologically sound and economically viable is an attractive alternative to the current cleanup methods that are very expensive. Phytoremediation technology is a cost effective one as it utilizes plants natural ability to suck the pollutant present in the water. There are many plants having this natural ability to up take the heavy metals and organic pollutants from air, soil and water. In this project we have treated the sewage coming out after primary treatment using phytoremediation techniques. In this project, the sewage which is taken from the primary treatment unit is further treated using phytoremediation technique that is the mustard plant is used for treating the sewage and thereby reducing the contaminants in wastewater to meet the wastewater disposal standards. Among various phytoremediation techniques phytovolatilization found to be effective in removing the pollutant as BOD, COD, Turbidity, Total dissolved solids, Kjeldahl nitrogen. The phytovolatilization showed the best removal of BOD up to 59.44 , COD up to 60.02 , Turbidity up to 97.83 , Total dissolved solids up to 31.35 , Kjeldahl nitrogen 97.46 . Karthika. V "Treatment of Sewage by Phytoremediation method using Izndian mustard Plant" Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-4 | Issue-5 , August 2020, URL: https://www.ijtsrd.com/papers/ijtsrd31644.pdf Paper Url :https://www.ijtsrd.com/engineering/environmental-engineering/31644/treatment-of-sewage-by-phytoremediation-method-using-izndian-mustard-plant/karthika-v
Chromium-induced growth inhibition and alteration of biochemical parameters i...ijtsrd
The hydroponically grown plants of Ocimum basilicum L. were exposed to varying levels of K2Cr2O7 (0, 5, 10, 25 -µM). The plants were tested for various morphological and biochemical parameters on 3rd and 5th day after treatment. Chromium (Cr) resulted in reduction of plant length and biomass. The deleterious effects of the hexavalent chromium on O. basilicum were further confirmed by the reductions in chlorophyll a and b contents, soluble protein and while as the free amino acid and proline contents were increased. The study concludes that chromium causes stress in the Ocimum basilicum plants and thus alters various morphological and biochemical parameters. Ruqaya Jabeen"Chromium-induced growth inhibition and alteration of biochemical parameters in Ocimum basilicum L." Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-2 | Issue-2 , February 2018, URL: http://www.ijtsrd.com/papers/ijtsrd8329.pdf http://www.ijtsrd.com/chemistry/other/8329/chromium-induced-growth-inhibition-and-alteration-of--biochemical-parameters-in-ocimum-basilicum-l/ruqaya-jabeen
In-vitro antioxidant and GC-MS analysis ethanolic extract of poly herbal drugSkyfox Publishing Group
Antioxidants play an important role in inhibiting and scavenging free radicals, thus providing protection to human against
infections and degenerative diseases. Current research is now directed towards natural antioxidants originated from plants due to safe
therapeutics. Poly herbal drugs is used in Indian traditional medicine for a wide range of various ailments. To understand the mechanism
of pharmacological actions, antioxidant properties of the Poly herbal drugs extract were tested using standard in vitro models. The
ethanolic extract of Poly herbal drugs exhibited strong scavenging effect on superoxide, nitric oxide radical and reducing power radical
scavenging assay. The free radical scavenging effect of Poly herbal drugs extract was comparable with that of the reference antioxidants.
The data obtained in the present study suggests that the extract of Poly herbal drugs have potent Invitro antioxidant and Anti Diabetic
activity against free radicals, prevent oxidative damage to major biomolecules and afford significant protection against oxidative damage.
4. optimization of culture condition for enhanced decolorization of reactive ...Darshan Rudakiya
Many synthetic azo dyes and their metabolites are toxic, carcinogenic, and
mutagenic so removal of azo dyes using cost-effective and eco-friendly method is
major aspect.Comamonas acidovorans MTCC 3364 has been routinely reported for
different steroid bioconversion and heavy metal removal. The main purpose of this
study is to check the decolorization efficiency of Comamonas acidovorans MTCC
3364 for different dyes and to optimize the condition which gives maximum
decolorization of Reactive Orange 16 dye. The effect of various physicochemical
parameters including condition, carbon and nitrogen sources, temperature,pH and
dye concentration were studied. The % decolorization of dye was determined by
UV Visible spectroscopy. This bacterial strain efficiently decolorizes Reactive
Orange 16 at 37oC, pH 6.85 within 24 hours giving 99.03 ± 0.5 % dye
decolorization under optimum environmental conditions.
NANOTECHNOLOGY: APPLICATION IN CROP NUTRTIONHARISH J
Nanotechnology can be applied to crop nutrition through the use of nanofertilizers. Nanofertilizers are fertilizers encapsulated in nanoparticles ranging from 1 to 100 nm in size. Their small size allows for slow and controlled release of nutrients, increasing fertilizer use efficiency and reducing environmental pollution. Research has shown nanofertilizers can increase crop yields, nutrient uptake, and enzyme activity compared to conventional fertilizers. However, more research is still needed to fully understand their effects on plants and minimize environmental risks before they can be widely adopted.
This document discusses the potential for nanopesticides to provide more effective and environmentally friendly pest control compared to traditional chemical pesticides. It notes that nanopesticides can utilize nanoencapsulation or nanoparticles of metals like silver, zinc, copper, and titanium dioxide to control pests and pathogens. While showing promise, more research is still needed to fully understand the interactions of nanoparticles with plants, soils, and organisms as well as their environmental impacts. The document advocates for more field studies to validate nanoparticle effects on various crop-pest systems and addresses their potential for nutrient leaching.
International Journal of Engineering and Science Invention (IJESI) is an international journal intended for professionals and researchers in all fields of computer science and electronics. IJESI publishes research articles and reviews within the whole field Engineering Science and Technology, new teaching methods, assessment, validation and the impact of new technologies and it will continue to provide information on the latest trends and developments in this ever-expanding subject. The publications of papers are selected through double peer reviewed to ensure originality, relevance, and readability. The articles published in our journal can be accessed online.
preparation and foliar application of oligochitosanIJEAB
Oligochitosan with weight average molecu-lar weight (Mw) of 5000 g/mol was prepared by gamma Co-60 radiation degradation of 4% chitosan solution containing 0.5% H2O2 at 21 kGy. Nanosilica with size of 10 – 30 nm was synthesized by calcination of acid treated rice husk at 700o C for 2 h. The mixture of 2% oligo-chitosan-2% nanosilica was prepared by dispersion of nanosilica in oligochitosan solution. Oligochitosan, nanosilica and their mixture were characterized by gel permeation chromatography (GPC), transmission electr-on microscopy (TEM), X-ray diffraction (XRD), energy dispersive x-ray spectroscopy (EDX), Ultraviolet-visible spectroscopy (UV-Vis), and Furrier transform infrared spectroscopy (FT-IR). Effect of foliar application of oli-gochitosan and oligochitosan-nanosilica on soybean seed yield was conducted in experimental field. Results indi-cated that soybean seed yield increased 10.5 and 17.0% for oligochitosan and oligochitosan-nanosilica, respect-tively for the control. Radiation degraded oligo-chitosan and its mixture with nanosilica can be potentially used for cultivation of soybean with enhanced seed yield.
1. The study examined the effects of different concentrations of cobalt (50, 100, 150, 200, and 250 mg/kg soil) on biochemical constituents and antioxidant enzyme activities in the green gram plant Vigna radiata.
2. Biochemicals like sugars, starch, amino acids, and proteins decreased with increasing cobalt concentration, while antioxidant enzymes like catalase decreased but peroxidase and polyphenol oxidase increased.
3. The 50 mg/kg cobalt level benefited plant growth and biochemical/antioxidant parameters compared to higher concentrations and the control, suggesting it acts as a beneficial trace element at low levels.
Green Synthesis of ZnO Nanoparticles using Jasminum Fluminense Leaf Extract a...ijtsrd
1) The document describes the green synthesis of Zinc Oxide (ZnO) nanoparticles using the leaf extract of Jasminum Fluminense.
2) The synthesized nanoparticles were characterized using UV-Visible spectroscopy, Fourier Transform Infrared Spectroscopy (FTIR), and Transmission Electron Microscopy (TEM).
3) UV-Visible spectroscopy showed an absorption peak at 289.9 nm confirming the formation of ZnO nanoparticles. TEM images showed the particles were hexagonal and spherical in shape with an average size of 20 nm.
Similar to Effect of some cover crops and their secondary metabolites on nitrous oxide (N2O) emission by Pseudomonas denitrifiers isolated from chemically fertilized corn farm soil (20)
Climate Change All over the World .pptxsairaanwer024
Climate change refers to significant and lasting changes in the average weather patterns over periods ranging from decades to millions of years. It encompasses both global warming driven by human emissions of greenhouse gases and the resulting large-scale shifts in weather patterns. While climate change is a natural phenomenon, human activities, particularly since the Industrial Revolution, have accelerated its pace and intensity
Recycling and Disposal on SWM Raymond Einyu pptxRayLetai1
Increasing urbanization, rural–urban migration, rising standards of living, and rapid development associated with population growth have resulted in increased solid waste generation by industrial, domestic and other activities in Nairobi City. It has been noted in other contexts too that increasing population, changing consumption patterns, economic development, changing income, urbanization and industrialization all contribute to the increased generation of waste.
With the increasing urban population in Kenya, which is estimated to be growing at a rate higher than that of the country’s general population, waste generation and management is already a major challenge. The industrialization and urbanization process in the country, dominated by one major city – Nairobi, which has around four times the population of the next largest urban centre (Mombasa) – has witnessed an exponential increase in the generation of solid waste. It is projected that by 2030, about 50 per cent of the Kenyan population will be urban.
Aim:
A healthy, safe, secure and sustainable solid waste management system fit for a world – class city.
Improve and protect the public health of Nairobi residents and visitors.
Ecological health, diversity and productivity and maximize resource recovery through the participatory approach.
Goals:
Build awareness and capacity for source separation as essential components of sustainable waste management.
Build new environmentally sound infrastructure and systems for safe disposal of residual waste and replacing current dumpsites which should be commissioned.
Current solid waste management situation:
The status.
Solid waste generation rate is at 2240 tones / day
collection efficiently is at about 50%.
Actors i.e. city authorities, CBO’s , private firms and self-disposal
Current SWM Situation in Nairobi City:
Solid waste generation – collection – dumping
Good Practices:
• Separation – recycling – marketing.
• Open dumpsite dandora dump site through public education on source separation of waste, of which the situation can be reversed.
• Nairobi is one of the C40 cities in this respect , various actors in the solid waste management space have adopted a variety of technologies to reduce short lived climate pollutants including source separation , recycling , marketing of the recycled products.
• Through the network, it should expect to benefit from expertise of the different actors in the network in terms of applicable technologies and practices in reducing the short-lived climate pollutants.
Good practices:
Despite the dismal collection of solid waste in Nairobi city, there are practices and activities of informal actors (CBOs, CBO-SACCOs and yard shop operators) and other formal industrial actors on solid waste collection, recycling and waste reduction.
Practices and activities of these actor groups are viewed as innovations with the potential to change the way solid waste is handled.
CHALLENGES:
• Resource Allocation.
Presented by The Global Peatlands Assessment: Mapping, Policy, and Action at GLF Peatlands 2024 - The Global Peatlands Assessment: Mapping, Policy, and Action
Microbial characterisation and identification, and potability of River Kuywa ...Open Access Research Paper
Water contamination is one of the major causes of water borne diseases worldwide. In Kenya, approximately 43% of people lack access to potable water due to human contamination. River Kuywa water is currently experiencing contamination due to human activities. Its water is widely used for domestic, agricultural, industrial and recreational purposes. This study aimed at characterizing bacteria and fungi in river Kuywa water. Water samples were randomly collected from four sites of the river: site A (Matisi), site B (Ngwelo), site C (Nzoia water pump) and site D (Chalicha), during the dry season (January-March 2018) and wet season (April-July 2018) and were transported to Maseno University Microbiology and plant pathology laboratory for analysis. The characterization and identification of bacteria and fungi were carried out using standard microbiological techniques. Nine bacterial genera and three fungi were identified from Kuywa river water. Clostridium spp., Staphylococcus spp., Enterobacter spp., Streptococcus spp., E. coli, Klebsiella spp., Shigella spp., Proteus spp. and Salmonella spp. Fungi were Fusarium oxysporum, Aspergillus flavus complex and Penicillium species. Wet season recorded highest bacterial and fungal counts (6.61-7.66 and 3.83-6.75cfu/ml) respectively. The results indicated that the river Kuywa water is polluted and therefore unsafe for human consumption before treatment. It is therefore recommended that the communities to ensure that they boil water especially for drinking.
Evolving Lifecycles with High Resolution Site Characterization (HRSC) and 3-D...Joshua Orris
The incorporation of a 3DCSM and completion of HRSC provided a tool for enhanced, data-driven, decisions to support a change in remediation closure strategies. Currently, an approved pilot study has been obtained to shut-down the remediation systems (ISCO, P&T) and conduct a hydraulic study under non-pumping conditions. A separate micro-biological bench scale treatability study was competed that yielded positive results for an emerging innovative technology. As a result, a field pilot study has commenced with results expected in nine-twelve months. With the results of the hydraulic study, field pilot studies and an updated risk assessment leading site monitoring optimization cost lifecycle savings upwards of $15MM towards an alternatively evolved best available technology remediation closure strategy.
ENVIRONMENT~ Renewable Energy Sources and their future prospects.tiwarimanvi3129
This presentation is for us to know that how our Environment need Attention for protection of our natural resources which are depleted day by day that's why we need to take time and shift our attention to renewable energy sources instead of non-renewable sources which are better and Eco-friendly for our environment. these renewable energy sources are so helpful for our planet and for every living organism which depends on environment.
Optimizing Post Remediation Groundwater Performance with Enhanced Microbiolog...Joshua Orris
Results of geophysics and pneumatic injection pilot tests during 2003 – 2007 yielded significant positive results for injection delivery design and contaminant mass treatment, resulting in permanent shut-down of an existing groundwater Pump & Treat system.
Accessible source areas were subsequently removed (2011) by soil excavation and treated with the placement of Emulsified Vegetable Oil EVO and zero-valent iron ZVI to accelerate treatment of impacted groundwater in overburden and weathered fractured bedrock. Post pilot test and post remediation groundwater monitoring has included analyses of CVOCs, organic fatty acids, dissolved gases and QuantArray® -Chlor to quantify key microorganisms (e.g., Dehalococcoides, Dehalobacter, etc.) and functional genes (e.g., vinyl chloride reductase, methane monooxygenase, etc.) to assess potential for reductive dechlorination and aerobic cometabolism of CVOCs.
In 2022, the first commercial application of MetaArray™ was performed at the site. MetaArray™ utilizes statistical analysis, such as principal component analysis and multivariate analysis to provide evidence that reductive dechlorination is active or even that it is slowing. This creates actionable data allowing users to save money by making important site management decisions earlier.
The results of the MetaArray™ analysis’ support vector machine (SVM) identified groundwater monitoring wells with a 80% confidence that were characterized as either Limited for Reductive Decholorination or had a High Reductive Reduction Dechlorination potential. The results of MetaArray™ will be used to further optimize the site’s post remediation monitoring program for monitored natural attenuation.
Kinetic studies on malachite green dye adsorption from aqueous solutions by A...Open Access Research Paper
Water polluted by dyestuffs compounds is a global threat to health and the environment; accordingly, we prepared a green novel sorbent chemical and Physical system from an algae, chitosan and chitosan nanoparticle and impregnated with algae with chitosan nanocomposite for the sorption of Malachite green dye from water. The algae with chitosan nanocomposite by a simple method and used as a recyclable and effective adsorbent for the removal of malachite green dye from aqueous solutions. Algae, chitosan, chitosan nanoparticle and algae with chitosan nanocomposite were characterized using different physicochemical methods. The functional groups and chemical compounds found in algae, chitosan, chitosan algae, chitosan nanoparticle, and chitosan nanoparticle with algae were identified using FTIR, SEM, and TGADTA/DTG techniques. The optimal adsorption conditions, different dosages, pH and Temperature the amount of algae with chitosan nanocomposite were determined. At optimized conditions and the batch equilibrium studies more than 99% of the dye was removed. The adsorption process data matched well kinetics showed that the reaction order for dye varied with pseudo-first order and pseudo-second order. Furthermore, the maximum adsorption capacity of the algae with chitosan nanocomposite toward malachite green dye reached as high as 15.5mg/g, respectively. Finally, multiple times reusing of algae with chitosan nanocomposite and removing dye from a real wastewater has made it a promising and attractive option for further practical applications.
Improving the viability of probiotics by encapsulation methods for developmen...Open Access Research Paper
The popularity of functional foods among scientists and common people has been increasing day by day. Awareness and modernization make the consumer think better regarding food and nutrition. Now a day’s individual knows very well about the relation between food consumption and disease prevalence. Humans have a diversity of microbes in the gut that together form the gut microflora. Probiotics are the health-promoting live microbial cells improve host health through gut and brain connection and fighting against harmful bacteria. Bifidobacterium and Lactobacillus are the two bacterial genera which are considered to be probiotic. These good bacteria are facing challenges of viability. There are so many factors such as sensitivity to heat, pH, acidity, osmotic effect, mechanical shear, chemical components, freezing and storage time as well which affects the viability of probiotics in the dairy food matrix as well as in the gut. Multiple efforts have been done in the past and ongoing in present for these beneficial microbial population stability until their destination in the gut. One of a useful technique known as microencapsulation makes the probiotic effective in the diversified conditions and maintain these microbe’s community to the optimum level for achieving targeted benefits. Dairy products are found to be an ideal vehicle for probiotic incorporation. It has been seen that the encapsulated microbial cells show higher viability than the free cells in different processing and storage conditions as well as against bile salts in the gut. They make the food functional when incorporated, without affecting the product sensory characteristics.
Improving the Management of Peatlands and the Capacities of Stakeholders in I...
Effect of some cover crops and their secondary metabolites on nitrous oxide (N2O) emission by Pseudomonas denitrifiers isolated from chemically fertilized corn farm soil
1. International Journal of Environmental & Agriculture Research (IJOEAR) ISSN:[2454-1850] [Vol-2, Issue-2, February- 2016]
Page | 91
Effect of some cover crops and their secondary metabolites on
nitrous oxide (N2O) emission by Pseudomonas denitrifiers
isolated from chemically fertilized corn farm soil
Takaaki Nishiyama1
, Daisuke Haba2
, Yasuyuki Hashidoko3
Faculty of Agriculture, Hokkaido University, Kita 9, Nishi 9, Kita-ku, Sapporo 060-8589, Japan
Abstract—Using a Pseudomonas denitrifying bacterium, which had been isolated from Japanese Andisol corn farm as an
active nitrous oxide (N2O) emitter and likely to be missing nosZ gene, we investigated denitrification-regulating activity of
some cover crops or green manure plants against this N2O emitter. In the preliminary screening, root exudates from the 10
seedlings of yellow flowering leaf mustard (Brassica juncea) and crimson clover (Trifolium incarnatum) showed 50%
repression of the N2O emission by an incomplete denitrifier Pseudomonas sp. 05CFM15-6D. When direct extracts of the
seedling roots with MeOH were assayed, however, only the seedlings of B. juncea showed a remarkable inhibition of
bacterial cell growth and N2O emission at concentration equivalent to 10 seedlings. The root extract from B. juncea
equivalent to 2 to 4 seedlings maintained inhibiting activity toward N2O emission, while it did not affect bacterial cell
growth. Conversely, water-soluble fraction from aboveground of European small radish (Raphanus sativus var. sativus)
sprouts showed statistically significant acceleration of N2O emission (P<0.01) with slight but insignificant cell growth
activation. As some secondary metabolites are uniquely contained in these cover crops, suppressing or accelerating activity
of such phytochemicals in N2O emission was also investigated. Allyl isothiocyanate at 30 µM markedly inhibited N2O
emission of the Pseudomonas denitrifier but not suppressed its cell growth. In contrast, methyl isothiocyanate sinigrin,
cyanamide, and betanin did not affect on N2O emission of the denitrifier at 150-300 µM.
Keywords—cover crops, Brassica juncea, N2O emission, allyl isothiocyanate, Raphanus sativus var. sativus.
I. INTRODUCTION
Nitrous oxide (N2O) is an active greenhouse gas contributing more than 7% of global warming [1]. N2O, one of the most
active greenhouse gases, has a strong global warming potential and contributes to depleting ozone layer in atmosphere [2]. In
global scale, agricultural soils are recognized as major anthropogenic N2O emission sources. In particular, agriculture soil
plays dominant roles in N2O emission with widespread use of nitrogenous fertilizers and manure to drive emission increment
[3,4], in which N cycle, biological denitrification is the most important process [5]. Denitrification is a microbial nitrate
respiration process, in which the oxidized nitrogen compounds served as electron acceptors for energy production in
anaerobic conditions [6,7].
Cover crops, including some Brassicaceae and Fabaceae plants are often introduced into farmland to be subjected to crop
rotation or maintain soils before leaving idle. The cover crops often play a role of green manure to reserve mineral nutrition
in the soil, while they are often cultivated for the purpose of repression and regulation of weeds [8,9] or soil-borne disease
causative soil microorganisms [10,11]. In particular, yellow flowering leaf mustard (Brassica juncea), white mustard
(Sinapis alba) [12], and hairry vetch (Vicia villosa) [13] are cover crops used worldwide for biofumigation and weed control.
If any annual plants can suppress N2O emission from the farmland soil, such cover crops are useful for cleaning of
denitrifiers from the cropland soils. As cover crops are generally plowed into soil for fertilization, it may affect on
denitrification processes in soil if plant tissues contained secondary metabolites active against denitrification-associated
enzymes. In this paper, we wish to report unique responses of methanolic extracts from seedlings of some cover crops on an
active N2O emitter isolated from Andisol of corn farmland in Shicizunai, Japan. Also, we further discuss on soil management
strategy to minimize N2O emission from fertilized soils in croplands.
II. MATERIAL AND METHOD
2.1 Plant seeds and seedlings: Plant seeds used in this study are as follows: yellow flowering leaf mustard (Brassica
juncea cv. Kibananochikara) and crimson clover (Trifolium incarnatum cv. Strawberry Candle) were purchased from Takii
Seed Ltd. (Kyoto, Japan), and European small radish (Raphanus sativus var. sativus cv. Sakuranbohatsukadaikon) was from
Atariya Noen Ltd. (Katri, Chiba Prefecture, Japan). Hairy vetch (Vicia villosa cv. Mamesuke) was from Snow Seed Co
(Sapporo, Japan). As phytochemicals used, allyl isothiocyanate, methylisothiocyanate, and cyanamide were purchased from
2. International Journal of Environmental & Agriculture Research (IJOEAR) ISSN:[2454-1850] [Vol-2, Issue-2, February- 2016]
Page | 92
Wako (Osaka, Japan), whereas sinigrin hydrate was from TCI (Tokyo, Japan). Betanin was extracted from red beetroot
cultivated by ourselves and isolated using a reverse-phase column chromatograph technique [14].
2.2 N2O emission assay: To investigate the main causative microorganisms of N2O production in autumn,
Winogradsky’s mineral solution-based, a gellan gum soft gel medium [15] was used. As mineral N for the substrate of N2O
production, KNO3 (each 500 mg L-1
) was added to the Winogradsky’s mineral solution [16]. The pH of the solution was
adjusted to 6.0 with 1 M H2SO4, followed by filtration through a polytetrafluoroethylene (PTFE) membrane (pore size, 0.45
µm; Merck Millipore, Billerica, MA, USA) to remove insoluble mineral residues. Gellan gum powders was 0.3 % (w/v), and
powders of the gelling matrix was heated until melted, mixed well, and then cooled to room temperature. A 10.0 mL portion
of the medium was poured into a 30-mL gas chromatographic vial (Nichiden-Rika Glass Co., Kobe, Japan) sealed with a
butyl rubber plug and screw cap septum, and then autoclaved at 121 °C for 15 min. The headspace volume is 22.6 mL [17].
To obtain fresh inoculates for N2O emission assay, Pseudomonas sp. was shake-cultured in 50 mL of Winogradsky’s medium
supplemented with 0.5% sucrose at 110 rpm at 20 °C for 24 h in dark. Inoculates were collected from 50 mL cultured
medium by centrifuging at 8000 ×g at 4 °C for 10 min, washed with Milli-Q water several times, and then dissolved with
sterilized water. Only for the preliminary assay, bacterial cells pre-cultured on potato-dextrose agar (Nissui, Tokyo, Japan)
for 2 days at 25 °C were suspended into sterilized MilliQ water. The bacterial cell suspension (approximately 106
cells mL−1
,
OD660 of 0.4) was added to Winogradsky’s medium in the 30-mL gas chromatographic vials. After 7 days incubation at 20
°C in dark, the headspace gas was analyzed with GC. The initial medium containing 0.05% of sucrose and adjusted to pH
6.0, from which the N2O emitters were selected for further incubation to analyze optimum pH and N2O emission assay under
relatively poor nutrient conditions.
A 100 µL portion of cell suspension of Pseudomonas sp. 05CFM15-6D was inoculated to the assay medium and vortexted
for 1 min. After incubation at 20 °C for 7 days in dark, 1 mL of the headspace gas was analyzed with a gas chromatograph
(Shimadzu GC-14B, Kyoto, Japan) equipped with an electron capture detector (ECD) (Shimadzu ECD-2014) using a 1 m
Porapak N column (Waters, Milford, MS, USA) [18].
2.3 Assay conditions for N2O production: Pseudomonas sp. 05CFM15-6D (accession no. LC007968.1) used for
the culture-based N2O emission assay was an incomplete denitrifier isolated from thawing soil of corn farms as a culturable
and active N2O emitter. Identification and characteristics of this isolate was described in another paper [19]. As this
bacterium is likely a heterotrophic saprophyte, it grew well in potato-dextrose medium.
To evaluate effect of allyl isothiocyanate on N2O emitters, a 100-µL portion of 2-30 mM allyl isothiocyanate in MeOH was
added to 10 mL of Winogradsky’s medium supplemented with 5 mg KNO3. The final concentration of allyl isothiocyanate
was 20-300 µM. In the same process, methyl isothiocyanates, a glucosinolate sinigrin hydrate, and cyanamide, an
allelopathic principle of hairy vetch, were dissolved in MeOH and also tested at 150, 1000, and 300 µM respectively, while
betanin dissolved in water was subjected to dilution into 500 µM for final concentration in the assay medium. For these
phytochemicals initially dissolved in MeOH, the control medium contained 100 µL MeOH.
III. RESULTS
3.1 Effect of root extracts from seedlings of cover crops on bacterial N2O emission: Using the culture-based
N2O emission assay to evaluate activity in regulation of N2O emission by Pseudomonas sp. 05CFM15-6D, extracts from
seedlings of some cover crops showed slight repression of N2O emission, particularly the root extracts from the 6 seedlings
of yellow flowering leaf mustard (B. juncea) and 12 seedlings of hairy vetch (V. villosa) (Table 1 and Fig. 1). However, the
extracts precisely adjusted as equivalent to 10 seedlings showed less activity in the N2O emission. As marked activities, only
the root extracts from B. juncea and crimson clover (T. incarnatum) seedlings showed statistically significant inhibition of
N2O emission (P <0.001 and <0.01 respectively). Inhibition ratio of the root extract from B. juncea was more than 90%,
while only 35% in the extract of T. incarnatum (Fig. 2).
TABLE 1
SEEDLINGS OF COVER CROPS USED FOR PRELIMINARY N2O EMISSION ASSAY
Cover crop seedling Root biomass (dry weight, g) Seedling number Metabolites from root Amount (mg)
Brassica juncea 2.68 59
extract
exudate
56
72
Raphanus sativus var. sativus 1.60 110
extract
exudate
48
44
Trifolium incarnatum 1.24 187
extract
exudate
46
45
Vicia villosa 4.85 122
extract
exudate
41
39
3. International Journal of Environmental & Agriculture Research (IJOEAR) ISSN:[2454-1850] [Vol-2, Issue-2, February- 2016]
Page | 93
FIG. 1. EFFECT OF ROOT EXTRACT/EXUDATE FROM COVER CROPS ON N2O EMISSION BY PSEUDOMONAS SP. 05CFM15-
6D.
Amount of extracts of these seedlings (B. juncea, R. sativus var. sativus, T, incarnatum, and V. villosa) applied to the N2O
emission assay is equivalent to 5.9, 11.0, 18.7, 12.2 seedlings respectively. Incubation was done at 25 °C, for 6 days. Bar is ±
standard deviation. Replication, n=5.
FIG. 2. EFFECT OF MEOH EXTRACTS FROM Brassica juncea AND Trifolium incarnatum ON N2O EMISSION.
MeOH extracts of cover crops (B. juncea and T. incarnatum) were equivalent to 10 seedlings. Amounts of the extracts
applied to the N2O emission assay from root extract, root exudate, and aboveground of T. incarnatum seedlings are 3.8, 6.2,
and 23.6 mg, while root extracts and root exudates from B. juncea root are 3.2 and 11.4 mg respectively. Incubation was
done at 25 °C, for 3 days. Bar is ± standard deviation. Replication, n=3. **P<0.01, ***P<0.001.
The root exudate equivalent to 4 seedlings cultivated in an approximately 10-times larger scale of the seedlings did not show
any N2O emission-suppressing activity. Only the aboveground of B. juncea extracted with MeOH showed the relatively clear
inhibition of N2O emission by Pseudomonas sp. strain 05CFM15-6D. Conversely, methanolic extract from the aboveground
of European small radish (R. sativus var. sativus) showed statistically significant stimulating activity twice as large as
4. International Journal of Environmental & Agriculture Research (IJOEAR) ISSN:[2454-1850] [Vol-2, Issue-2, February- 2016]
Page | 94
untreated control (Fig. 3). This activity was found only in water-soluble fraction, which had passed through a C18-reverse
phase silica gel with water.
FIG. 3. EFFECT OF MEOH EXTRACTS EQUIVALENT TO FOUR SEEDLINGS OF Brassica juncea AND Rahanus sativus cv.
sativus ON N2O EMISSION BY Pseudomonas SP. 05CFM15-6D.
MeOH extracts of two cover crops (B. juncea and R. sativus var. sativus, as the root and aboveground parts respectively)
were divided into MeOH soluble and insolubles. The latter was re-dissolved in water. All the extracts equivalent to 4
seedlings were subjected to N2O emission assay. Incubation was done at 25 °C, for 4 days. Bar is ± standard deviation.
Replication, n=5. *P<0.05, **P<0.01, ***P<0.001.
3.2 Effect of phytochemicals to characterize family and species of cover crops tested: At 30 µM or higher,
allyl isothiocyanate, a major isothocyanate responsible for the pungent taste of brassicaceous mustard, radish, horseradish,
and wasabi [20,21], completely inhibited N2O emission (Fig. 4). Up to concentration of 150 µM, allyl isothiocyanate visibly
allowed cell growth of Pseudomonas sp. 05CFM15-6D (data not shown). As the N2O emitter used for this assay is a highly
motile bacterium, this bacterium generally forms haze-like colonies in the soft gel medium. However, bacterial cells cultured
upon exposure to 30-150 µM at pH 6.0, the bacterial cells grown in the soft gel medium had lost their swimming ability to
form particle-like colonies [15].
FIG. 4. EFFECT OF ALLYL ISOTHIOCYANATE ON N2O EMISSION.
5. International Journal of Environmental & Agriculture Research (IJOEAR) ISSN:[2454-1850] [Vol-2, Issue-2, February- 2016]
Page | 95
A 100-µL portion of ally isothiocyanate dissolved in medium. To the control (MeOH), 100 µL MeOH was added, while
another control (water) contained no organic solvent. Filled arrow shows the threshold concentration of allyl isothiocyanate
for complete inhibition of N2O emission by Pseudomonas sp. 05CFM15-6D. Incubation was done at 25 °C, for 6 days. Bar is
± standard deviation. Replication, n=5.
In contrast, a glucosinolate sinigrin that is a precursor of allyl isothiocyanate did not suppress N2O emission and cell growth
performance of Pseudomonas sp. 05CFM15-6D even at 1000 µM (Fig. 5A). Methyl isothiocyanate showed activity at 300
µM, but not at 150 µM. Similarly, both cyanamide and betanin were inactive at 300 µM and 500 µM respectively (Fig. 5B,
C, and D).
FIG. 5. EFFECT OF SOME OTHER PHYTOCHEMICALS ON N2O EMISSION.
Incubation was done at 25 °C, for 3-6 days. Bar is ± standard deviation.
IV. DISCUSSION
As oxidation of ammonia in soil known as nitrification is leads to nitrogen loss due to provision of nitrate, substrate for
denitrification process in soil. Hence, some synthetic nitrification inhibitors, such as dicyandiamide, nitrapyrin, and thiourea,
have long been studied [22-24]. In current needs for sustainable food production, however, eco-friendly nitrification inhibitor
is awaited. One milestone is a discovery of a naturally-occurring nitrification inhibitor, brachialactone, from the root-exudate
of the poaceous grass Brachiaria humidicola [25]. Another important discovery is nitrification inhibitors from a cropping
plant, sorghum. Sakuranetin (4',5-dihydroxy-7-methoxyflavanone) and sorgoleone (2-hydroxy-5-methoxy-[(8Z,11Z)-8,11,14-
pentadecatriene]-p-benzoquinone) produced by the roots of sorghum selectively inhibited ammonia monooxygenase of
Nitrosomonas (ED80 0.6 and 13.0 µM respectively) [26].
As our previous research revealed that 2 µM paraquat suppressed N2O emission by Pseudomonas denitrifiers, biological
resources for denitrification inhibitors to repress N2O emission was also predicted as the next target for the screening of
naturally occurring substances [16]. Thus, main purpose of this study is to demonstrate some possibilities of secondary
metabolites uniquely contained in cover crops cultivable for biofumigation or green manure. Some cover crops are important
candidates to relieve soil microbial community in the fertilized farm soil where N2O is actively emitted, because some cover
crops are known to change soil microbial community structures [27].
Both isothiocyanate and cyanamide possessed a ketene-like 1,2-double bond in the molecule, and these chemical structures
are similar with N2O (Fig. 5). We therefore tested isothiocyanates and cyanamide as candidates for repressing agent against
N2O emission. Allyl isothiocyanate showed a clear repressive activity in N2O emission by the Pseudomonas denitrifier (Fig.
4). However, methyl isothiocyanate did not show any inhibitory effect on the N2O emitter at 150 µM (Fig. 5B). The inactive
action of methyl isothiocyanate implied that isothiocyanate moiety is not fundamental in allyl isothiocyanate as the inhibiting
agent against N2O emission. In the same assay system, we also tested cyanamide, obtainable as allelopathic substances from
6. International Journal of Environmental & Agriculture Research (IJOEAR) ISSN:[2454-1850] [Vol-2, Issue-2, February- 2016]
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hairy vetch [13]. Although some biological activities of cyanamide have been reported, this compound did not affect N2O
emission at 300 µM (Fig. 5C).
As betanin that is richly contained in red beetroot is an outstanding antioxidant phytochemical, we estimated that betanin
could inhibit N2O emission by denitrifiers because nitrate respiration is a series of redox-reaction on inorganic nitrogen
molecules and electron donors [6]. However, neither repressing nor accelerating effect of betanin was observed at 500 µM in
our culture-based N2O emission assay (Fig. 5D).
Not only seedlings but also mature plants of B. juncea are rich in sinigrin, a precursor of allyl isothiocyanate [28]. Therefore,
after the tillage of this cover crop with topsoil, a large amount of allyl isothiocyanate would be released effectively to the
tilled farm soil du to mechanical damages. Our culture-based N2O emission assay using Pseudomonas sp. 05CFM15-6D
implied that allyl isothiocyanate selectively represses nitrate respiration-associating enzymes. Together with the effect of B.
juncea as cover crop that stimulates soil microbial diversity and population density, allyl isothiocyanate may practically
suppress N2O emission from cropland soils.
As 1000 µM sinigrin did not repress N2O production of Pseudomonas sp. 05CFM15-6D in the culture-based N2O assay (Fig.
5A), it is obvious that Pseudomonas sp. 05CFM15-6D does not possess bacterial myrosinase. This speculation is acceptable
because not many proteobacteria possess bacterial myrosinase that degrades sinigrin to release allyl isothiocyanate from the
substrate [29]. Hence, effect of B. juncea on biofumigation for the tilled soil is probably due to plant myrosinase activated
after the mechanical damage by the tillage to provide allyl isothiocyanate in micro/macro-pore space of soil.
V. CONCLUSION
The N2O emitter Pseudomonas sp. 05CFM15-6D is a facultative anaerobe, and its N2O emission progresses under anaerobic
conditions with an excessive organic matter utilizable for the copiotrophic and saprophytic denitrifier [19]. Therefore, green
manure as a possible accelerator for N2O emission from the tilled soil is great concern. Indeed, we found that MeOH extract
from the aboveground of R. sativum var. sativum seedlings accelerated N2O emission by the incomplete denitrifiers in this
study (Fig. 3), while allyl isothiocyanate from B. juncea showed marked suppression of N2O emission by an incomplete
denitrifier in the culture-based bioassay (Fig. 4). We therefore imply necessity of risk management for such tilling the green
manure and pre-harvest vegetable crops.
ACKNOWLEDGEMENTS
This research was supported by Grants-in-Aid for Scientific Researches A and B (26252058 and 26304042 to YH) from the
Japan Society for the Promotion of Science.
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