This study isolated Shewanella oneidensis from soil in Basra, Iraq. S. oneidensis showed high resistance to cadmium (1000 mg/L) and lead (700 mg/L). It effectively accumulated both metals at different concentrations and exposure times. Transmission electron microscopy confirmed S. oneidensis accumulated cadmium and lead intracellularly, causing morphological changes. The results suggest S. oneidensis has potential for bioremediating sites contaminated with heavy metals like cadmium and lead.
Phylogenetic Analysis of the Potential Microorganism for Remediation of Heavy...CSCJournals
The present research work has been carried out to study the waste disposal contaminated site for its physico chemical and microbial characterization and identification of potential microorganism capable of bioaccumulation and biodegradation of heavy metals. The ambient conditions present in the metal contaminated environment shows the values: pH(5.4),temperature(30°C), moisture(11.71%), nutrients; Nitrogen(0.2mg/l), phosphorus(22.65mg/l) and sulphur(559.3mg/l) respectively. The biological parameters studied indicate Dissolved oxygen (7.4mg/l), Biological oxygen demand (3.8 mg/l), Chemical oxygen demand (64.6 mg/l). The microbial consortium identified was found to survive and multiply in the present environmental conditions. Microbial consortium was sequenced and compared using Bioinformatics tools like BLAST, ClustalW and PHYLIP. In order to identify potential microorganism, microbial consortium was exposed to increasing concentrations of heavy metals viz 5mg/l, 25mg/l, 50mg/l, 100mg/l up to 800mg/l with special reference to Iron. At a concentration of 500mg/l, only one microorganism was found survived and multiplied. This shows that potential microorganism was only survived at higher concentration of iron. The 16SrRNA sequence and phylogenetic tree characterized the organism as Klebsiella pneumoniae, which was also confirmed by biochemical tests. The potential microorganism identified by BLAST technique can be used for remediation of the heavy metal from contaminated environment.
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
Removal of Cr (VI) Through the Use of the Agroindustrial Residue of the Perse...CrimsonpublishersMCDA
We analyzed the Chromium (VI) removal capacity in aqueous solution by the Persea americana biomass, using the diphenyl carbazide method to evaluate the metal concentration. Biosorption at different pH (1, 2, 3, and 4) was evaluate for different times. We too studied the effect of temperature in the range of 28 to 60 °C and the removal at different initial concentrations of Cr (VI) of 200 to 1000mg/L. Therefore, the highest biosorption of the metal (50mg/L) occurs within 270 minutes, at pH of 1.0 and 28 °C. According to temperature, the highest removal was observing at 60 °C, in 45 minutes, when the metal is completely adsorbed. At the analyzed concentrations of Cr (VI), fungal biomass, showed excellent removal capacity, besides it removes efficiently the metal in situ (100% removal in earth and water contaminated, after 5 and 6 days of incubation, 5 and 10g of biomass, 10g of earth and 100mL of water; so, it can be used to eliminate it from industrial wastewater.
https://crimsonpublishers.com/mcda/fulltext/MCDA.000570.php
For more open access journals in Crimson Publishers please click on link: https://crimsonpublishers.com
For more articles on journal of agronomy and crop science please click on below link: https://crimsonpublishers.com/mcda/
Triclosan Persistence in Environment and Its Potential Toxic Effects on AlgaeAJASTJournal
Triclosan (TCS) is widely used as an antibacterial agent in various industrial products, such as textile goods, soap, shampoo, liquid toothpaste and cosmetics, and often detected in wastewater effluent. Triclosan is highly toxic to aquatic animals, and is particularly highly toxic to the algae, which was used as a test organism in this study. Algae represent the first nutritional base on the aquatic food chain due to their ability to synthesize organic molecules using sunlight and carbon dioxide. Thus, the cultivation of algae has been an integral part for the production of commercially important species on aquaculture. This has been the reason to make great efforts in order to understand effect of triclosan to natural periphyton communities (algae). However, there is a paucity of data on the toxicity of triclosan and its effects on aquatic organisms. In this study, the toxicity of triclosan to a microalga was examined. The present investigation showed that “chlorophyll a” pigment in control algae was 5.92 mg/L and it decreased, when algae was treated with different concentration of triclosan (10-50 ppm). The study revealed that, as the concentration of triclosan increased then algae growth declined. It was observed that conductivity also increased because of decreased “chlorophyll a” and decreased phytoplankton levels. This result indicates that triclosan exerts a marked influence on algae, which are important organisms being the first-step producers in the ecosystem; therefore, the possible destruction of the balance of the ecosystem is expected if triclosan is discharged into the environment at high levels. The bioaccumulation of TCS in human impregnation from foodstuff exposure (in particular fish) and likely risk for human population also.
Phylogenetic Analysis of the Potential Microorganism for Remediation of Heavy...CSCJournals
The present research work has been carried out to study the waste disposal contaminated site for its physico chemical and microbial characterization and identification of potential microorganism capable of bioaccumulation and biodegradation of heavy metals. The ambient conditions present in the metal contaminated environment shows the values: pH(5.4),temperature(30°C), moisture(11.71%), nutrients; Nitrogen(0.2mg/l), phosphorus(22.65mg/l) and sulphur(559.3mg/l) respectively. The biological parameters studied indicate Dissolved oxygen (7.4mg/l), Biological oxygen demand (3.8 mg/l), Chemical oxygen demand (64.6 mg/l). The microbial consortium identified was found to survive and multiply in the present environmental conditions. Microbial consortium was sequenced and compared using Bioinformatics tools like BLAST, ClustalW and PHYLIP. In order to identify potential microorganism, microbial consortium was exposed to increasing concentrations of heavy metals viz 5mg/l, 25mg/l, 50mg/l, 100mg/l up to 800mg/l with special reference to Iron. At a concentration of 500mg/l, only one microorganism was found survived and multiplied. This shows that potential microorganism was only survived at higher concentration of iron. The 16SrRNA sequence and phylogenetic tree characterized the organism as Klebsiella pneumoniae, which was also confirmed by biochemical tests. The potential microorganism identified by BLAST technique can be used for remediation of the heavy metal from contaminated environment.
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
Removal of Cr (VI) Through the Use of the Agroindustrial Residue of the Perse...CrimsonpublishersMCDA
We analyzed the Chromium (VI) removal capacity in aqueous solution by the Persea americana biomass, using the diphenyl carbazide method to evaluate the metal concentration. Biosorption at different pH (1, 2, 3, and 4) was evaluate for different times. We too studied the effect of temperature in the range of 28 to 60 °C and the removal at different initial concentrations of Cr (VI) of 200 to 1000mg/L. Therefore, the highest biosorption of the metal (50mg/L) occurs within 270 minutes, at pH of 1.0 and 28 °C. According to temperature, the highest removal was observing at 60 °C, in 45 minutes, when the metal is completely adsorbed. At the analyzed concentrations of Cr (VI), fungal biomass, showed excellent removal capacity, besides it removes efficiently the metal in situ (100% removal in earth and water contaminated, after 5 and 6 days of incubation, 5 and 10g of biomass, 10g of earth and 100mL of water; so, it can be used to eliminate it from industrial wastewater.
https://crimsonpublishers.com/mcda/fulltext/MCDA.000570.php
For more open access journals in Crimson Publishers please click on link: https://crimsonpublishers.com
For more articles on journal of agronomy and crop science please click on below link: https://crimsonpublishers.com/mcda/
Triclosan Persistence in Environment and Its Potential Toxic Effects on AlgaeAJASTJournal
Triclosan (TCS) is widely used as an antibacterial agent in various industrial products, such as textile goods, soap, shampoo, liquid toothpaste and cosmetics, and often detected in wastewater effluent. Triclosan is highly toxic to aquatic animals, and is particularly highly toxic to the algae, which was used as a test organism in this study. Algae represent the first nutritional base on the aquatic food chain due to their ability to synthesize organic molecules using sunlight and carbon dioxide. Thus, the cultivation of algae has been an integral part for the production of commercially important species on aquaculture. This has been the reason to make great efforts in order to understand effect of triclosan to natural periphyton communities (algae). However, there is a paucity of data on the toxicity of triclosan and its effects on aquatic organisms. In this study, the toxicity of triclosan to a microalga was examined. The present investigation showed that “chlorophyll a” pigment in control algae was 5.92 mg/L and it decreased, when algae was treated with different concentration of triclosan (10-50 ppm). The study revealed that, as the concentration of triclosan increased then algae growth declined. It was observed that conductivity also increased because of decreased “chlorophyll a” and decreased phytoplankton levels. This result indicates that triclosan exerts a marked influence on algae, which are important organisms being the first-step producers in the ecosystem; therefore, the possible destruction of the balance of the ecosystem is expected if triclosan is discharged into the environment at high levels. The bioaccumulation of TCS in human impregnation from foodstuff exposure (in particular fish) and likely risk for human population also.
Comparison of three different Bioleaching systems for Li recovery from lepido...Suby Mon Benny
Nature article about Lithium Bioextraction by J. Sedlakova-Kadukova, R. Marcincakova, A. Luptakova, M. Vojtko, M. Fujda and P. Pristas explained in a simple manner.
Evaluation of Cadmium tolerant Fungi in the dying Staff and their removal Pot...AI Publications
Cadmium tolerance and bioremediation capacity of seven isolates including Aspergilus versicolor, Aspergillus fumigatus, Paecilomyces sp.9, Paecilomyces sp.G, Terichoderma sp, Microsporum sp,Cladosporium sp were determined. Minimum inhibitory concentration values among 2,000-6,000 mg lˉ1proved great ability of isolated strains to survive in cadmium polluted environments. The most tolerant fungi, Aspergilus versicolor, showed tolerance index of 0.93 in 100 mg lˉ1 cadmium agar media. Fungal resistance against cadmium is depended directly on strain’s biological function. A. versicolor was found to bioaccumulation over 7.67mg of cadmium per 1 g of mycelium, followed by 6.546, 6.354, and 6.286, 6.134 by Paecilomyces sp, Aspergilus fumigatus, Microsporum sp and Terichoderma sp, respectively. It can be noted that tolerance of the strains appears to be independent from bioaccumulation capacity. Finally, the results indicated that A. versicolor could be a prospective candidate for bioremediation processes.
Research Inventy : International Journal of Engineering and Scienceinventy
Research Inventy : International Journal of Engineering and Science is published by the group of young academic and industrial researchers with 12 Issues per year. It is an online as well as print version open access journal that provides rapid publication (monthly) of articles in all areas of the subject such as: civil, mechanical, chemical, electronic and computer engineering as well as production and information technology. The Journal welcomes the submission of manuscripts that meet the general criteria of significance and scientific excellence. Papers will be published by rapid process within 20 days after acceptance and peer review process takes only 7 days. All articles published in Research Inventy will be peer-reviewed.
In recent years, nanoparticles that have size of 1-100 nm is widely used for textile, pharmacy,
cosmetic and treatment of industrial wastewater. Producing and using of nanoparticles widely, causes
important accumulation in nature and toxicity on ecosystem. Knowledge of potential toxicity of nanoparticles is
limited. In this study, six different nanoparticles nano-zinc oxide, nano-silicon dioxide, nano-cerium oxide,
nano-aluminum oxide, nano-hafnium oxide, and nano-tantalum oxide which used commonly, were studied to
investigate toxic impacts on organisms. We studied nine different acute toxicity test (bacteria – Escherichia coli
(gram negative bacteria) ; bacteria – Bacillus cereus (gram positive bacteria) ; bacteria – Vibrio fischeri
(bioluminescences bacteria) ; methane Archae Bacteria ; yeast – Candida albicans ; mold – Aspergillus niger ;
algae – Chlorella sp. ; Crustacea – Daphnia magna ; lepistes - Poecillia reticula) for the effect of
nanoparticles to different trophic levels. In general, the most toxic nanoparticle is nano-zinc oxide and the least
toxic nanoparticle is nano-hafnium oxide. Among the used organisms in acute toxicity test; the most sensitive
organism is algae - Chlorella sp ;the most resistant organism is fish- Poecillia reticula.
Secondary Metabolites of the Entomopathogenic Fungus, Cladosporium cladospori...Premier Publishers
Cladosporium cladosporioides is one of the promising entomopathogenic fungi acting as insect-pathogenic microorganism or can be used as a source of toxins against insect pests. Ethyl acetate extract of the secondary metabolites of C. cladosporioide was obtained, and its volatile constituents were characterized using GC/MS technique. Also, two major compounds were isolated and identified as 3-phenyl propanoic acid (6) and 3-(4β-hydroxy-6-pyranonyl)-5-isopropylpyrrolidin-2-one (7). It's worthy to mention that this isolated compound (7), is reported from C. cladosporioides for the first time. Also, the toxicity of the ethyl acetate extract of the secondary metabolites of C. cladosporioides against both adults and nymphs of cotton aphid, A. gossypii was determined. Data showed that C. cladosporioides ethyl acetate extract was most effective against nymphs showing LC50 of 24.5827 ppm, LC90 of 128.7385 ppm and toxicity index of 100%, while, it showed LC50 of 36.6959 ppm, LC90 of 154.4394 ppm and toxicity index of 76.69% against adults.
The International Journal of Engineering & Science is aimed at providing a platform for researchers, engineers, scientists, or educators to publish their original research results, to exchange new ideas, to disseminate information in innovative designs, engineering experiences and technological skills. It is also the Journal's objective to promote engineering and technology education. All papers submitted to the Journal will be blind peer-reviewed. Only original articles will be published.
The papers for publication in The International Journal of Engineering& Science are selected through rigorous peer reviews to ensure originality, timeliness, relevance, and readability.
Comparison of three different Bioleaching systems for Li recovery from lepido...Suby Mon Benny
Nature article about Lithium Bioextraction by J. Sedlakova-Kadukova, R. Marcincakova, A. Luptakova, M. Vojtko, M. Fujda and P. Pristas explained in a simple manner.
Evaluation of Cadmium tolerant Fungi in the dying Staff and their removal Pot...AI Publications
Cadmium tolerance and bioremediation capacity of seven isolates including Aspergilus versicolor, Aspergillus fumigatus, Paecilomyces sp.9, Paecilomyces sp.G, Terichoderma sp, Microsporum sp,Cladosporium sp were determined. Minimum inhibitory concentration values among 2,000-6,000 mg lˉ1proved great ability of isolated strains to survive in cadmium polluted environments. The most tolerant fungi, Aspergilus versicolor, showed tolerance index of 0.93 in 100 mg lˉ1 cadmium agar media. Fungal resistance against cadmium is depended directly on strain’s biological function. A. versicolor was found to bioaccumulation over 7.67mg of cadmium per 1 g of mycelium, followed by 6.546, 6.354, and 6.286, 6.134 by Paecilomyces sp, Aspergilus fumigatus, Microsporum sp and Terichoderma sp, respectively. It can be noted that tolerance of the strains appears to be independent from bioaccumulation capacity. Finally, the results indicated that A. versicolor could be a prospective candidate for bioremediation processes.
Research Inventy : International Journal of Engineering and Scienceinventy
Research Inventy : International Journal of Engineering and Science is published by the group of young academic and industrial researchers with 12 Issues per year. It is an online as well as print version open access journal that provides rapid publication (monthly) of articles in all areas of the subject such as: civil, mechanical, chemical, electronic and computer engineering as well as production and information technology. The Journal welcomes the submission of manuscripts that meet the general criteria of significance and scientific excellence. Papers will be published by rapid process within 20 days after acceptance and peer review process takes only 7 days. All articles published in Research Inventy will be peer-reviewed.
In recent years, nanoparticles that have size of 1-100 nm is widely used for textile, pharmacy,
cosmetic and treatment of industrial wastewater. Producing and using of nanoparticles widely, causes
important accumulation in nature and toxicity on ecosystem. Knowledge of potential toxicity of nanoparticles is
limited. In this study, six different nanoparticles nano-zinc oxide, nano-silicon dioxide, nano-cerium oxide,
nano-aluminum oxide, nano-hafnium oxide, and nano-tantalum oxide which used commonly, were studied to
investigate toxic impacts on organisms. We studied nine different acute toxicity test (bacteria – Escherichia coli
(gram negative bacteria) ; bacteria – Bacillus cereus (gram positive bacteria) ; bacteria – Vibrio fischeri
(bioluminescences bacteria) ; methane Archae Bacteria ; yeast – Candida albicans ; mold – Aspergillus niger ;
algae – Chlorella sp. ; Crustacea – Daphnia magna ; lepistes - Poecillia reticula) for the effect of
nanoparticles to different trophic levels. In general, the most toxic nanoparticle is nano-zinc oxide and the least
toxic nanoparticle is nano-hafnium oxide. Among the used organisms in acute toxicity test; the most sensitive
organism is algae - Chlorella sp ;the most resistant organism is fish- Poecillia reticula.
Secondary Metabolites of the Entomopathogenic Fungus, Cladosporium cladospori...Premier Publishers
Cladosporium cladosporioides is one of the promising entomopathogenic fungi acting as insect-pathogenic microorganism or can be used as a source of toxins against insect pests. Ethyl acetate extract of the secondary metabolites of C. cladosporioide was obtained, and its volatile constituents were characterized using GC/MS technique. Also, two major compounds were isolated and identified as 3-phenyl propanoic acid (6) and 3-(4β-hydroxy-6-pyranonyl)-5-isopropylpyrrolidin-2-one (7). It's worthy to mention that this isolated compound (7), is reported from C. cladosporioides for the first time. Also, the toxicity of the ethyl acetate extract of the secondary metabolites of C. cladosporioides against both adults and nymphs of cotton aphid, A. gossypii was determined. Data showed that C. cladosporioides ethyl acetate extract was most effective against nymphs showing LC50 of 24.5827 ppm, LC90 of 128.7385 ppm and toxicity index of 100%, while, it showed LC50 of 36.6959 ppm, LC90 of 154.4394 ppm and toxicity index of 76.69% against adults.
The International Journal of Engineering & Science is aimed at providing a platform for researchers, engineers, scientists, or educators to publish their original research results, to exchange new ideas, to disseminate information in innovative designs, engineering experiences and technological skills. It is also the Journal's objective to promote engineering and technology education. All papers submitted to the Journal will be blind peer-reviewed. Only original articles will be published.
The papers for publication in The International Journal of Engineering& Science are selected through rigorous peer reviews to ensure originality, timeliness, relevance, and readability.
«СОВЕТНИК» – современный клубный дом в стенах исторического особняка начала XX века.
«СОВЕТНИК» расположен на одной из старинных и красивейших улиц Москвы по адресу: Большая Дмитровка 7/5 строение 2.
Особенное звучание старинной московской улице задают ритмы исторических фасадов, линии кованых фонарей, тени террас уличных кафе и свет элегантных залов ресторанов.
Большая Дмитровка архитектурно открывает нам центр Старого города с великой историей, который сегодня стал современным европейским центром, центром успешной жизни с его неповторимой энергетикой.
27 квартир, пентхаус, с террасы которого открываются виды на исторический центр Москвы, стильный интерьер лобби, внимание к каждой детали – это «СОВЕТНИК».
An investigation on heavy metal tolerance properties of bacteria isolated fro...AbdullaAlAsif1
The presence of high concentration of toxic heavy metals in industrial waste directly leads to contamination of receiving soil and water bodies and has deleterious impact on both human health and aquatic life. In the present study samples from textile mill effluent from different areas of Jessore city were analyzed for the identification and characterization of bacteria which shows tolerance to Copper, Mercury and Zinc. The bacterial isolates were characterized on the basis of their morphological and physiological studies including size and shape of the organisms, arrangement of the cells, presence or absence of spores, regular or irregular forms, gram reaction, cultural characteristics, IMViC test, H 2S production, nitrate reduction, deep glucose agar test etc. All the bacterial isolates belonged to 3 genera Bacillus, Enterobacter and Pseudomonas. All the gram positive isolates used in our study showed highest level of tolerance to Zn and moderate level of tolerance to Cu while gram negative isolates showed higher tolerance to Zn in comparison with Cu in nutrient broth. But all of the isolates showed almost no tolerance to Hg. So, our bacterial isolates have the probability to use in the treatment of industrial effluent containing heavy metals and thus pollution due to heavy metal can be controlled. The goal of this study was to identify heavy metal tolerant bacteria from the textile effluent. This kind of study is very significant for broader investigation to obtain data about metal tolerant bacteria considering their potential use for bioremediation and about the interactions between metals and bacteria.
Removal of heavy metals (Cr, Cd, Ni and Pb) using fresh water algae (Utricula...Innspub Net
A study was conducted to check the efficiency of different fresh water algae for removing heavy metals (Cr, Cd, Ni and Pb) from contaminated water. The three most abundant indigenous algal species namely Ulothrix tenuissima, Oscillatoria tenuis and Zygogonium ericetorum were collected from fresh water channels of Parachinar, Pakistan and brought to the laboratory of Soil and Environmental Sciences Department at the University of Agriculture, Peshawar Pakistan for proper identification. To check the efficiency for removing heavy metals artificial contaminated water was prepared and was inoculated with mix culture of above mentioned algae and incubated for 10 days. After incubation algal species were removed from water through centrifugation and was dried, digested and analyzed for heavy metals. The results showed that the concentration of all heavy metals was substantially reduced in the algal inoculated contaminated water. The analysis of algal biomass showed that considerable amount of metals and other elements were recovered in algae. Among the tested algal species, Zygogonium ericetorum showed maximum removal Ni(99.40ug) and Cr(66.84ug) from contaminated water followed by Oscillatoria tenuis with 84ug(Ni) and 64.83ug(Cr) respectively. However Oscillatoria tenuis showed maximum removal of Cd(41.00ug) than the other algal species. Similarly Zygogonium ericetorum showed maximum removal of Pb (451ug) followed by Ulothrix tenuissima where 441ug was recorded. Highest amount Cd, and Ni were recovered in Zygogonium ericetorum biomass while highest amount of Cr and Pb were recorded in the biomass of Oscillatoria tenuis. Finally it could be concluded that algae have efficiently removed heavy metals from contaminated water. Further research is needed to test other algal species for removal of heavy metal and other elements from the contaminated water.
Introduction
The food and water contamination with heavy metals is increasing due to the environmental pollutions. Heavy metals are the elements with the density of more than 5 g/cm3 and have become a serious problem as a result of the urbanization and industrialization. These toxic metals pollute water, soil, plants, and eventually foodstuffs and our bodies. Several methods exist to remediate heavy metal pollution in waters such as membrane filtration, ion exchange mechanisms, or by precipitation. Yet, these techniques are not cost effective, in some cases, and do produce wastes that need to be properly disposed of. Microbial bioremediation could be an alternative. The use of microbes for remediation of heavy metals has been well studied. Some microorganisms, especially soil bacteria, have the ability to tolerate these contaminants. In addition, certain bacterial strains are capable of binding to heavy metals or transforming them into less toxic forms. Low operating costs, usable in foodstuffs, selective removal for specific toxic metals, minimal use of chemicals (resulting in low sludge production) and high efficiencies at very low levels of heavy metals are some of the advantages of biosorption methods. In this regard, the purpose of this study was to investigate the ability of active and passive absorption of heavy metals by a number of Lactic Acid Bacteria (LAB) strains in laboratory environment and food.
Materials and Methods
Seven LAB isolates including Lacticaseibacillus casei (RTCC 1296-3), Lacticaseibacillus rhamnosus (RTCC 1293-2), Lactiplantibacillus plantarum (RTCC 1290), Limosilactobacillus fermentum (RTCC 1303), Enterococcus faecium (RTCC 2347), Lactobacillus helveticus (RTCC 1304) and Lactobacillus acidophilus (RTCC 1299) were obtained from Razi type culture collection (RTCC), located at Razi vaccine and Serum Research Institute, Iran. All isolates were cultured in MRS (Scharlau, Spain) broth medium, at 37 °C for 24 hours, under anaerobic conditions. Pure cultures were preserved for long term by freezing at -70°C with 20% Glycerol. Heavy metals including Nitrate of Pb (II), Cd (II) and Ni (II) were purchased from Merck (Darmstadt, Germany). All standard solutions were prepared from the stock solutions containing 1000 mgl-1 in distilled water. Other chemicals used in study including Nitric acid (65%) and Hydrogen peroxide (37%), were also purchased from Merck, Germany. This study was conducted in two in- vitro and in-vivo phases; in the in- vitro phase, seven strains of bacteria with probiotic properties (L. casei, L. rhamnosus, L. plantarum, L. fermentum, Ent. facium, L. helveticus and L. acidofilous) were screened and then their ability to bind to cadmium (Cd), Lead (Pb) and nickel (Ni) in aqueous solution was investigated. Then, in the in-vivo stage, three probiotic strains that had the highest biosorption efficiency in the previously stage were selected and their effect with a ratio of 1:1:1 and contact time of 15 and 30 min
Health risk assessment of consuming heavy metal contaminated benthic seafood,...Premier Publishers
This study evaluated health risks associated with the consumption of a seafood (bivalve - Anadara (Senilia) senilis) contaminated with some heavy metals in southern Nigeria. Atomic absorption spectrophotometry was used for metal analysis. Mean metal concentrations (µgg-1) was in the order of Zn(12.96±1.0)> Pb(4.69±0.6)> Cr(2.91±0.7)> Ni(2.47±0.2)> Cu(2.03±0.3)> Cd(1.68±0.2). Mean concentrations of Cr, Cu and Zn were below their respective FAO/WHO recommended limits while those of Ni, Cd and Pb exceeded. The Estimated daily intake-EDI values of all metals were less than their respective reference oral doses-RFD implying minimal health risk. The target hazard quotient (non-carcinogenic) and hazard index-HI had values <1suggesting minimal health risk of non-carcinogenic origin but HI value showed potency of increase. The value of Incremental Lifetime Cancer Risk-ILCR ranged from 10-5-10-2 with Ni and Cd within the acceptable range of 10-4-10-6 while Cr and Pb exceeded the limit. The target cancer risk-TR had values of 10-3 indicating moderate to high risk according to the New York State Department of Health classification. The study concluded the presence of moderate to high carcinogenic risk due to Cr and Pb for consumers of heavy metal contaminated seafood (bivalves) in southern Nigeria. Minimal consumption and further action are advised with regular monitoring to detect changes.
Removal of Lead Ion Using Maize Cob as a BioadsorbentIJERA Editor
The intensification of industrial activity and environmental stress greatly contributes to the significant rise of
heavy metal pollution in water resources making threats on terrestrial and aquatic life. The toxicity of metal
pollution is slow and interminable, as these metal ions are non bio-degradable. The most appropriate solution for
controlling the biogeochemistry of metal contaminants is sorption technique, to produce high quality treated
effluents from polluted wastewater. Maize cob readily available was used as sorbent for the removal of lead ions
from aqueous media. Adsorption studies were performed by batch experiments as a function of process
parameters such as sorption 500ppm,2.5g, 400minutes, 400 rpm and 5 PH. Concentration, Dosage, time, rpm,
and pH. I have found that the optimized parameters are Freundlich model fits best with the experimental
equilibrium data among the three tested adsorption isotherm models. The kinetic data correlated well with the
Lagergren first order kinetic model for the adsorption studies of lead using maize cob. It was concluded that
adsorbent prepared from maize cob as to be a favorable adsorbent and easily available to remove the heavy
metal lead (II) is 95 % and can be used for the treatment of heavy metals in wastewater.
The present study intended to compare the efficiency of the wetland plants Phragmites australis (cav.)
Trin. ex Steudel and Cyperus papyrus L. for the accumulation of heavy metals. Maximum accumulation
of the heavy metals Pb (132.5-175 μg/g DW), Zn (97.5-100 μg/g DW) and Cr (80.5-90 μg/g DW) was
recorded in roots of the two wetland plants C. papyrus and P. australis, respectively. Cadmium showed
the lowest metal accumulation in the tissues of both plants (0.55-5.5 μg/g DW). C. papyrus roots
accumulated higher levels of most metals than those of P. australis. Heavy metals were shown to be not
only accumulated in roots of both plants but also were translocated to the shoots and accumulated in the
harvestable plant parts. The results showed variation in the levels of the heavy metals accumulated in the
different parts of C. papyrus and P. australis, in spite of being planted at the same site and subjected to
the same conditions. The potential use of Phragmites australis and Cyperus papyrus in phytoremediation
is also discussed.
Objectives :-
* Characterization and study of biochar.
*To examine biochar adsorption capacity.
*To determine the effect of KMnO4 as modifying agent on biochar adsorption.
A pilot study on effect of copper and cadmium toxicity in Tilapia Mossambicusresearchanimalsciences
Cu and Cd is trace element for most organisms including fish, but above certain limit Cu and Cd will be toxic. The present study was conducted to evaluate the toxic effect of Cu and Cd on Tilapia mossambicus via estimating the acute 96h median lethal concentration (LC50) value. A total 120 number of Tilapia mossambicus fingerlings were subjected to 12 numbers 20-L aquaria. Fish were exposed to 0.0, 2.0, 4.0, 6.0, 8.0 and 10.0mg Cu and Cd/L for 4 days. Each dose was represented by two aquaria. Fish was daily observed and dead fish were removed immediately. The data obtained were evaluated using Behrens-Karber’s Method. The 96 h LC50 value of Cu for Tilapia mossambicus was calculated to be 6.0mg Cu/L with Behrens-Karber’s Method. The 96 h LC50 value of Cd for Tilapia mossambicus was calculated to be 4.8mg Cd/L with Behrens-Karber’s Method. The behavioral changes of Tilapia mossambicus were primarily observed. It could be concluded that Tilapia mossambicus species slightly sensitive to Cu and Cd when compare both metal cadmium is more toxic than copper for the fish species.
Article Citation:
Anushia C, Sampath kumar P and Selva Prabhu A.
A Pilot Study on Effect of Copper and Cadmium Toxicity in Tilapia Mossambicus.
Journal of Research in Animal Sciences (2012) 1(1): 020-027.
Full Text:
http://janimalsciences.com/documents/AS0008.pdf
A Pilot Study on Effect of Copper and Cadmium Toxicity in Tilapia Mossambicus researchanimalsciences
Cu and Cd is trace element for most organisms including fish, but above certain limit Cu and Cd will be toxic. The present study was conducted to evaluate the
toxic effect of Cu and Cd on Tilapia mossambicus
via estimating the acute 96h median lethal concentration (LC 50 ) value. A total 120 number of
Tilapia mossambicus fingerlings were subjected to 12 numbers 20 L aquaria. Fish were exposed to 0.0, 2.0,
4.0, 6.0, 8.0 and 10.0mg Cu and Cd/L for 4 days. Each dose was represented by two aquaria. Fish was daily observed and dead fish were removed immediately. The data obtained were evaluated using Behrens - Karber’s Method. The 96 h LC 50 value of Cu for Tilapia mossambicus was calculated to be 6.0mg Cu/L with Behrens - Karber’s Method. The 96 h LC
50 value of Cd for Tilapia mossambicus was calculated to be 4.8mg Cd/L with Behrens - Karber’s Method. The behavioral changs of Tilapia mossambicus
were primarily observed. It could be concluded that Tilapia mossambicus species slightly sensitive to Cu and Cd when compare both metal
cadmium is more toxic than copper for the fish species.
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.
2. pollution is presently attracting more attention from
environmentalists worldwide.
Lead (II) is a heavy metal poison which forms
complexes with oxo-groups in enzymes to affect nearly
all steps in the process of hemoglobin synthesis and
porphyrin metabolism. Toxic levels of Pb (II) in man have
been associated with encephalopathy appropriations and
mental delay (Ademorati, 1996). Conventional physico-
chemical methods such as electrochemical treatment, ion
exchange, precipitation, reverse osmosis evaporation
and sorption (Kadirvelu et al., 2001, 2002) have been
used for removing heavy metals but are economically
expensive and have disadvantages. Bioremediation is a
natural process which depends on bacteria, fungi and
plants to altering pollutants as these organisms perform
their normal life functions. These organisms have the
ability of exploiting chemical contaminants as an energy
source in their metabolic processes. Therefore,
bioremediation affords alternative tool to destroy or
reduce the risky contaminants through biological activity
with an effective cost (Salem et al., 2012).
Microbial populations in metal polluted environments
become metals resistant (Prasenjit and Sumathi, 2005)
so the response of microorganisms towards toxic heavy
metals is of importance in view of the interest in the
reclamation of polluted sites (Shankar et al., 2007).
Microorganisms uptake metals either actively
(bioaccumulation) and/or passively (biosorption)
(Shumate and Strandberg, 1985; Anders and Hubert,
1992; Hussein et al., 2004). Bioaccumulation is the active
method of metal accumulation by living cells. The
capacity of living cells to remove metal ions from
environment is influenced by environmental growth
conditions, as temperature, pH and biomass
concentrations (Abd-El-Raheem et al., 2013).
TEM is a useful technique that can help to localize and
to identify metals deposited within or around microbial
cells. Identification of the site of accumulation is important
as it can give clues to the biochemical mechanisms
driving metal accumulation. Biological materials which
are largely composed of light elements such as C, N, H,
O, P, and S, do not deflect the electron beam to the same
degree. Thus, it is possible to visualize metals against the
faint image of a bacterial cell (Lloyd and Macaskie, 2002).
The present study, aims at isolating S. oneindensis
from Basra soil, south of Iraq, and evaluating metals
bioaccumulation ability, and also studying the effect of
metals initial concentration, contact times, and determine
the cellular localization of accumulated metals within this
bacterium by using Transmission electron microscope.
MATERIALS AND METHODS
Isolation of bacteria
Three soil samples (30 g each) were collected from AL-Zubair
district west of Basra city- Iraq during January 2013. The samples
were collected using a sterile plastic bag and transferred within 2 h
Jaafar et al. 371
to laboratory for analysis. One gram of air dried soil sample was
serially diluted using sterilized distilled water and spread over
nutrient agar. The plates were incubated at 30°C for 24 h.
Bacterial characterization
Properties of the bacteria included gram stain, citrate utilization,
indole production, methyl red, nitrate reduction, Voges Proskauer,
catalase, dextrose, mannitol and sucrose utilization, starch
hydrolysis, and gelatin liquefaction tests were determined according
to Sneath et al. (1986).
S16 rRNA gene based identification
The isolates were identified by sequencing of the 16S rRNA gene.
To determine the identification of bacterial isolates, the amplified
16S rRNA gene PCR products obtained from total genomic DNA
using primer set 27F (5′ AGAGTTTGATCCTGGCTCAG-3′) and
72.1492R (5′ GGTTACCTTGTTACGACTT-3′), (Lane et al., 1985)
were sequenced commercially. DNA sequences obtained were
compared to sequences available online in a GenBank database
(http://www.ncbi.nlm.nih.gov). Homology search was performed
using Bioinformatics tools available online BLASTn
www.ncbi.nlm.nih.gov/BLA (Altschul et al., 1997).
Determination of minimal inhibitory concentrations (MIC) for
Pb and Cd
The minimum inhibitory concentration (MIC) of Cd and Pb of
bacteria were determined by disc diffusion method. The
concentrations of Cd and Pb were between 40 to 2500 mgl-1
. Filter
paper discs were saturated with heavy metals for 30 min, and then
placed on nutrient agar plates and incubated for 24 h at 30°C. Pb
(NO3)2 and CdCl2 were used to prepare mother solution of these
metals in sterile distilled water and were used in various
concentrations. The lowest concentrations of Cd and Pb that
completely prevented growth of each bacterium were considered as
the MIC (Sethuraman and Kumar, 2011).
Bioaccumulation of heavy metals by bacteria
Bacteria were grown in LB broth containing 5, 10, 25 and 50 mgl-1
of lead and for cadmium 10, 20, 50 and 100 mgl-1
then incubated
for 2, 4, 6, 24 and 48 h at 30°C in a shaker incubator at 150 rpm.
Three replicates for each concentration have been done, and one
as a control. The bacterial cells were harvested by centrifugation at
6000 rpm for 15 min, and suspended in 1 ml of distilled water,
oven-dried at 80°C for 1 h and weighted. Metal concentrations were
measured by atomic absorption spectrophotometer. Control was
represented by the same microbial culture without heavy metals.
Each metals concentration is measured with two replicates
(Sprocati et al., 2006).
Transmission electron microscope
By centrifuging samples broth culture for 10 min at 3000 rpm, and
decanting the supernatant, fixing pellet with 4% gutaraldehyde for 4
h at 4°C and centrifuged again, decanting fixative and adding an
appropriate quantity animal serum to submerge sample, and
allowing serum to clot. It was washed three times with 0.1 M
Cacodylate buffer for 10 min. and Posted fix in 1% Osmium
tetrroxide for 2 h at 4°C. Also, it was washed again three times with
0.1 M Cacodylate buffer for 10 min. Dehydrating in series of
3. 372 Afr. J. Microbiol. Res.
Table 1. Biochemical characteristics of S. oneidensis isolate from
soils.
Tests Characteristics observed
Oxidase test +
Catalase test +
Indole formation -
Nitrate reduction -
Production of H2S +
Gelatin liquefaction +
Fermentation of
Sucrose +
Fructose +
D-glucose +
"+"and "-" indicate positive and negative reactions, respectively.
acetone of 35, 50, 75, 95, and 100% for 10, 10,10, 10 and 15 min
respectively. Finally, we make infiltration of the specimen with
acetone and resin:
Acetone: Resin Time
1 : 1 1 h
1 : 3 2 h
100% Overnight
100% 2 h
Embedding: Specimens were placed into beam capsule filled with
resin. Polymerization: polymerized in oven at 60°C for 24 h. Make
ultrasectioning, by choosing an area of interest, then cut for
ultrathin section, selecting the silver section, picking up a section
with a grid, then drying with filter paper. Finally staining with Uranyl
acetate for 15 min, and washed double distills water. Lead stained
for 10 min, and washed twice in distilled water. This work was done
at the Electron Microscope Laboratory Institute of Bioscience,
University Putra Malaysia.
RESULTS AND DISCUSSION
Characterization and molecular identification of
isolated bacteria
The selected bacterium was characterized and identified
by using conventional morphological, physiological and
biochemical tests (Table 1). It was presumptively
identified as Shewanella sp (Holt et al., 2005). The
sequence of 16S rRNA gene of this bacterium was
submitted to Blastn database 16S ribosomal RNA
sequences (Bacteria and Archaea) Megablast
http://www.ncbinlm.nih.gov/blast. It indicated a close
genetic relatedness of this bacterium with the rDNA
sequence of Shewanella oneidensis (Holt et al., 2005).
Minimum inhibitory concentration (MIC)
The MIC is the lowest concentration of the heavy metals
that completely inhibited bacterial growth (Froidevaux et
al., 2001) S. oneindensis showed significant resistance to
high concentrations of Pb and Cd (700 and 1000 mgl
-1
)
respectively. This may be considered new finding, that
the other studies showed different results. Chihomvu et
al. (2014) recorded MIC for Pb by Shewanella (4 Mm),
while MIC was 0 for Cd. Francis and Dodge (1988) and
Toes et al. (2008) demonstrated that, the tolerances
inhibited growth of different Shewanella strains
completely at 150 µM Co, 150 - 400 µM Zn, 75 - 150 µM
Cd, and 150 µM Cu when cultivated aerobically in 10%
LB broth. The effect of the medium on metal toxicity was
demonstrated in a study by Toes et al. (2008) where
higher tolerances of Cu by Shewanella between 75 and
750 µM in more nutrient rich media and the presence of
manganese oxides also reduce the toxicity of Cu.
Bioaccumulation
S. oneidensis as sulfate reducing bacteria has the
potential to enhance metal retention via extracellular
binding, cellular uptake and accumulation of metals,
oxidation/reduction processes, and surface mediated
mineral precipitation (Burkhardt, 2010). From results of
the present study, S. oneindensis was able to accumulate
Cd than Pb (26.77 and 3.98 mgg
-1
) at 48 h and at
concentrations 50 and 100 mgl
-1
respectively (Figures 1
and 2). The differences in this accumulation ability for
these two metals may be related to different toxicity of
these metals to this bacterium. From the results, the
accumulation of both metals increases with increasing
the time. Varghese et al. (2012) showed that, with
increasing time, the biomass of the bacterial strains
increased. Likewise, with an increase in biomass, the
heavy metals bioaccumulation also increased. The
results of the present study showed that the high amount
of accumulation occurs with high metals concentration
(50 and 100 mgl
-1
). These results agree with the results
reported by Odokuma and Akponah (2010), where they
concluded an increasing uptake pattern observed in the
respective test isolates as the initial concentration of the
various heavy metal salts were increased. These
observations suggested that metal uptake may involve
diffusion phenomenon, whereby metal ions move from
regions of high to low concentrations.
Transmission electron microscope
Cells were evaluated by TEM to observe the locations of
precipitate of metals in relation to the S. oneidensis cells.
In order to differentiate whether extracellular or
intracellular reduction occurred, the cells were stained
with uranyl acetate. Figure 3 has shown the cells before
being exposed to the metals (a). Dark precipitate can be
seen around the inside of the cell membrane, indicating
4. Jaafar et al. 373
Figure 1. Bioaccumulation of Pb by S. oneidensis during different incubation periods and
different concentrations.
Figure 2. Bioaccumulation of Cd by S. oneidensis during different incubation periods and
different concentrations.
intracellular Cd and Pb reduction has occurred (b and c).
Also, from Figure (3b and c) there were changes in size
and shape of cells and some cells have been lysed.
These results could add to the toxicity of the substance,
and ultimately results in cell death.
The cell surface morphology considerably changed
after metals exposure. The cellular localization of the
metals bound by the cells of the bacterium was located
mainly within the cell membrane. However, some
intracellular metal accumulates were also identified in the
cytoplasm of the bacterial cells. Merroun et al. (2005)
reported that, the cellular localization of the uranium
bound by the cells of three types of Acidithiobacillus
ferrooxidans was studied using TEM. Also, El-Helow et
al. (2000) reported that, cell surfaces of cultures treated
with cadmium chloride tended to be rough, suggesting
that the cell increased its surface to improve the
interaction of toxic substances with the cell surface.
Also, Singh et al. (2013), reported cell surface
morphological changes in Cryptococcus sp. after
exposure to heavy metals, and which could be observed
by the presence of shrunken and distorted cell wall in the
presence of Cd and depressions in the presence of Pb
and Zn.
Secretion of extracellular polymeric substance by
Desulfovibrio desulfuricans during biosorption of Zn and
Cu was reported to modify its cell surface morphology
(Chen et al., 2000). Similarly, El-Meleigy et al. (2013)
reported that, high dark dense cytoplasm due to Co
2+
precipitation is partially emptied with a very thick cell
wall; changing in the morphology of vegetative cells of
Bacillus firmus and Bacillus subtilis.
0
1
2
3
4
2 4 6 24 48
Bioaccumulation(ppm)
Time(hr)
Bioaccumulation of Pb
con. 5
con. 10
con. 25
con 50
control
Time (h)
0
5
10
15
20
25
30
Bioaccumulation(ppm)
2 4 6 24 48
Time( hr)
Bioaccumulation Cd
con 10
con20
con 50
con 100
control
Time (h)
5. 374 Afr. J. Microbiol. Res.
Figure 3. Transmission electron micrographs of S. oneidensis a: control, b: treated with 50 mgl-1
of Cd for
24 h, c: Treated with 50 mgl-1
of Pb for 24 h (Scale of bar 0.5 and 2 µm).
Conflict of interests
The authors have not declared any conflict of interests.
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