The document discusses optimizing the preparation of clove oil nanoemulsions as an effective antibacterial agent. It used the Taguchi method to determine the optimal conditions for producing nanoemulsions with droplets less than 50 nm that are stable and have low polydispersity. The key parameters optimized were clove oil concentration, emulsifier concentration, hydrophilic-lipophilic balance number, and ultrasonication time. The optimal conditions found were 50 nm droplet size, 0.49 polydispersity index, and -40.7 mV zeta potential. Testing showed the optimized nanoemulsion inhibited Escherichia coli and Bacillus cereus at 16 and 32 μg/ml respectively and killed them at 16
Removal of basic dye from aqueous solution by adsorption on melon husk inAlexander Decker
This document discusses a study that investigated the adsorption behavior of the cationic dye methylene blue in single, binary, and ternary solutions using melon husk as an adsorbent. Experiments showed that adsorption equilibrium was reached within 120 minutes for all systems. Kinetic data fit best to a pseudo-second order model. Isotherm data fit best to the Langmuir model for single systems and Freundlich model for binary and ternary systems. Adsorption was found to be thermodynamically feasible and exothermic for single and binary systems but endothermic for ternary systems.
Removal of Methylene Blue from Aqueous Solution by Adsorption using Low Cost ...ijsrd.com
The present study deals with removal of methylene blue (basic dye)from aqueous solution using a low cost activated carbon prepared from Delonix regia(gulmohar seed pods).Batch adsorption studies were conducted by varying the contact time adsorbent dosage and pH
This document summarizes a study on using natural coagulants from Moringa, corn, green bean, and tamarind seeds to decolorize textile wastewater. The study tested the coagulation efficiency of the different seeds at removing dyes under varying conditions of pH, coagulant dose, and contact time. Moringa seed extract showed the highest color removal rate of 86.45% and produced the lowest sludge content. The natural coagulants were found to be effective and environmentally-friendly alternatives to chemical coagulants for treating textile wastewater.
IRJET- Comparative Study on the Removal of Zinc from Synthetic Wastewater by ...IRJET Journal
This document studies the removal of zinc from synthetic wastewater using activated sawdust as an adsorbent. Sawdust was collected and activated through either acid activation using sulfuric acid or base activation using sodium hydroxide. Batch adsorption experiments were conducted to determine the optimal process parameters for zinc removal. The effects of adsorbent dosage, pH, contact time, and initial zinc concentration were evaluated. Maximum zinc removal of 98.68% for acid-activated sawdust and 99.58% for base-activated sawdust occurred at a dosage of 5g, pH of 5, contact time of 120 minutes, and initial concentration of 10ppm. The results indicate activated sawdust is an
This document discusses the adsorption of textile waste using biomass. Adsorption is the adhesion of atoms, ions, or molecules from a gas, liquid, or dissolved solid onto a surface. Certain methods are being introduced to adsorb materials through plant biomasses like mosses, leaves, and fruit waste or seeds. The parameters that affect adsorption include pH, adsorbent dose, contact time, initial concentration, temperature, and adsorbent size. Characterization techniques like SAM, FTIR, and XRD are used. Experiments are conducted to prepare synthetic dyes and measure their interaction and removal percentage with adsorbents. This process uses waste biomass, making it cost effective
Aimed to investigate the potential of untreated jute stick charcoal as an alternative adsorbent for the treatment of dye containing wastewater. Removal of methylene blue dye from aqueous solution using jute stick charcoal has been investigated. Liquid phase adsorption experiments were conducted. Batch adsorption studies are carried out by observing the effect of experimental parameters, namely, pH, adsorbent dose, contact time and initial methylene blue concentration. The maximum removal of MB dye was 90.57% at pH 9, contact time 120 min, adsorbent dose 3 g/L and 20 mg/L initial dye concentration. Kinetic studies showed that the biosorption of MB followed Pseudo second-order kinetics. The adsorption isotherms are described by the Langmuir and Freundlich isotherms. It was found that the Freundlich equation fit better than the Langmuir equation. The maximum adsorption capacity obtained from Langmuir isotherm equation at was 29.33 mg/g. To conclude, jute stick charcoal holds promise for methylene blue removal from aqueous solution and can be used for other dyes removal and applicable in dyeing industries in Bangladesh where centralized effluent treatment plant is absent.
Dye removal by adsorption on waste biomass - sugarcane bagasseMadhura Chincholi
This document discusses the use of bagasse as an adsorbent for removing dyes from wastewater. It provides background on dyes, their usage, and the issues they cause when discharged in wastewater. The document examines using raw and chemically activated bagasse to adsorb the dye methylene blue. It explores the adsorption process and how parameters like pH, contact time, adsorbent dose, and dye concentration affect adsorption. The results found chemically activated bagasse was more effective at lower pH levels, and equilibrium was reached within 45 minutes with optimal removal achieved using 12g/L of the chemically activated bagasse.
This document summarizes a graduation thesis on removing ibuprofen from aqueous solutions using adsorption on lentil and rice husk. It discusses the materials and methods used, including the adsorbents (rice husk and lentil husk), adsorbate (ibuprofen), and experimental procedures. The results and discussion section analyzes the effect of pH, adsorbent concentration, and temperature on ibuprofen adsorption. Optimum removal conditions were found to be pH 3, 20g/L rice husk concentration, and room temperature. Adsorption data fitted the Langmuir isotherm model well.
Removal of basic dye from aqueous solution by adsorption on melon husk inAlexander Decker
This document discusses a study that investigated the adsorption behavior of the cationic dye methylene blue in single, binary, and ternary solutions using melon husk as an adsorbent. Experiments showed that adsorption equilibrium was reached within 120 minutes for all systems. Kinetic data fit best to a pseudo-second order model. Isotherm data fit best to the Langmuir model for single systems and Freundlich model for binary and ternary systems. Adsorption was found to be thermodynamically feasible and exothermic for single and binary systems but endothermic for ternary systems.
Removal of Methylene Blue from Aqueous Solution by Adsorption using Low Cost ...ijsrd.com
The present study deals with removal of methylene blue (basic dye)from aqueous solution using a low cost activated carbon prepared from Delonix regia(gulmohar seed pods).Batch adsorption studies were conducted by varying the contact time adsorbent dosage and pH
This document summarizes a study on using natural coagulants from Moringa, corn, green bean, and tamarind seeds to decolorize textile wastewater. The study tested the coagulation efficiency of the different seeds at removing dyes under varying conditions of pH, coagulant dose, and contact time. Moringa seed extract showed the highest color removal rate of 86.45% and produced the lowest sludge content. The natural coagulants were found to be effective and environmentally-friendly alternatives to chemical coagulants for treating textile wastewater.
IRJET- Comparative Study on the Removal of Zinc from Synthetic Wastewater by ...IRJET Journal
This document studies the removal of zinc from synthetic wastewater using activated sawdust as an adsorbent. Sawdust was collected and activated through either acid activation using sulfuric acid or base activation using sodium hydroxide. Batch adsorption experiments were conducted to determine the optimal process parameters for zinc removal. The effects of adsorbent dosage, pH, contact time, and initial zinc concentration were evaluated. Maximum zinc removal of 98.68% for acid-activated sawdust and 99.58% for base-activated sawdust occurred at a dosage of 5g, pH of 5, contact time of 120 minutes, and initial concentration of 10ppm. The results indicate activated sawdust is an
This document discusses the adsorption of textile waste using biomass. Adsorption is the adhesion of atoms, ions, or molecules from a gas, liquid, or dissolved solid onto a surface. Certain methods are being introduced to adsorb materials through plant biomasses like mosses, leaves, and fruit waste or seeds. The parameters that affect adsorption include pH, adsorbent dose, contact time, initial concentration, temperature, and adsorbent size. Characterization techniques like SAM, FTIR, and XRD are used. Experiments are conducted to prepare synthetic dyes and measure their interaction and removal percentage with adsorbents. This process uses waste biomass, making it cost effective
Aimed to investigate the potential of untreated jute stick charcoal as an alternative adsorbent for the treatment of dye containing wastewater. Removal of methylene blue dye from aqueous solution using jute stick charcoal has been investigated. Liquid phase adsorption experiments were conducted. Batch adsorption studies are carried out by observing the effect of experimental parameters, namely, pH, adsorbent dose, contact time and initial methylene blue concentration. The maximum removal of MB dye was 90.57% at pH 9, contact time 120 min, adsorbent dose 3 g/L and 20 mg/L initial dye concentration. Kinetic studies showed that the biosorption of MB followed Pseudo second-order kinetics. The adsorption isotherms are described by the Langmuir and Freundlich isotherms. It was found that the Freundlich equation fit better than the Langmuir equation. The maximum adsorption capacity obtained from Langmuir isotherm equation at was 29.33 mg/g. To conclude, jute stick charcoal holds promise for methylene blue removal from aqueous solution and can be used for other dyes removal and applicable in dyeing industries in Bangladesh where centralized effluent treatment plant is absent.
Dye removal by adsorption on waste biomass - sugarcane bagasseMadhura Chincholi
This document discusses the use of bagasse as an adsorbent for removing dyes from wastewater. It provides background on dyes, their usage, and the issues they cause when discharged in wastewater. The document examines using raw and chemically activated bagasse to adsorb the dye methylene blue. It explores the adsorption process and how parameters like pH, contact time, adsorbent dose, and dye concentration affect adsorption. The results found chemically activated bagasse was more effective at lower pH levels, and equilibrium was reached within 45 minutes with optimal removal achieved using 12g/L of the chemically activated bagasse.
This document summarizes a graduation thesis on removing ibuprofen from aqueous solutions using adsorption on lentil and rice husk. It discusses the materials and methods used, including the adsorbents (rice husk and lentil husk), adsorbate (ibuprofen), and experimental procedures. The results and discussion section analyzes the effect of pH, adsorbent concentration, and temperature on ibuprofen adsorption. Optimum removal conditions were found to be pH 3, 20g/L rice husk concentration, and room temperature. Adsorption data fitted the Langmuir isotherm model well.
1. The document discusses supercritical carbon dioxide (CO2) dyeing as an alternative to conventional water-based dyeing.
2. Supercritical CO2 dyeing eliminates the use of water, chemicals, and auxiliaries in the dyeing process. It also reduces energy requirements compared to conventional dyeing.
3. The key advantages are that it produces no wastewater, reduces costs, and is more environmentally friendly than conventional dyeing.
Adsorption of Methylene blue and Malachite Green in Aqueous Solution using Ja...IJEAB
The adsorption of mixture of two basic dyes methylene blue and malachite green in aqueous solution onto jack fruit leaf ash in a batch system with respect to initial dye concentrations, pH, contact time, shaker speed and adsorbent doses was investigated.. The pseudo-first-order and pseudo-second- order kinetics model were used to describe the kinetic data. The rate constants at different pH values (3-9.1) were evaluated. The experimental data fitted well with the pseudo-second-order kinetic model. Equilibrium isotherms were analyzed by Langmuir, Freundlich and Temkin isotherm models. Maximum adsorption capacity was 20.41mg/g was achieved by Langmuir isotherm model. Error analysis was done to find the best model that described the experimental data well and it was the Langmuir model. The result indicated that jack fruit leaf ash could be fruitfully employed as low cost adsorbent for the removal of mixture of two basic dyes MB and MG from the wastewater.
Comparative Study for Adsorptive Removal of Coralene Blue BGFS Dye from Aqueo...IJERA Editor
Textile industries represent biggest impact on the environment due to high water consumption and waste water discharge as government control water pollution by setting strength regulation for waste water discharge, removal of color from waste water becomes more and more essential and attractive. Adsorption technology is very efficient in treatment of textile effluent. In this paper comparison of adsorption phenomena of textile dye Anthraquinone blue onto two different adsorbents MgO nano powder and Fe2O3 amorphous powder has been studied for removal of said dye from aqueous solutions. The adsorption of Anthraquinone blue on adsorbents occurs by studying the effects of adsorbent amount, dye concentration, contact time and pH of solution. All results found that MgO nano powder and Fe2O3 provide a fairly high dye adsorption capacity, which combined with their fulfilment of pollution control board’s standards, lack of pollution, lower environmental hazard and low-cost makes them promising for future applications. The present work also provides information on optimum value of different operating parameter for dye removal by two adsorbent.
ADSORPTION OF CONGO RED DYE AND METHYLENE BLUE DYE USING ORANGE PEEL AS AN A...Ajay Singh
This document discusses dyes and their adsorption using orange peel extract. It provides information on types of dyes and their harmful effects on wastewater. The document then describes an experiment where Congo red dye and methylene blue dye were adsorbed using orange peel extract over different time intervals. The percentage removal of Congo red dye was highest (23.25%) at 100 minutes, while methylene blue dye reached the highest removal rate (11.25%) at 20 minutes. In conclusion, the percentage dye removal increased with contact time and further experiments could explore additional dyes and adsorbents.
This document discusses using bagasse ash, a byproduct of sugar production, to treat industrial wastewater. It provides background on wastewater treatment technologies like biological, chemical, and physical methods. Adsorption using activated carbon from bagasse ash is proposed, which could remove 89% of acid orange dye from water. Producing activated carbon from a low-cost agricultural byproduct like bagasse ash makes it three times cheaper than conventional activated carbon. Further studies on column tests and regeneration are needed before commercializing bagasse ash activated carbon for industrial wastewater treatment.
Project report on Textile effluent treatment by electrochemical processBrijmohan Sharma
This document provides an overview of a student project on treating textile effluent water using an electrochemical process. It includes a certificate verifying the students conducted the project, an acknowledgements section thanking those who helped with the project, and a preface describing how the project helped the students learn. The contents section outlines the document, which explores using electrochemical treatment to make textile wastewater safer before discharge by reducing parameters like BOD, COD and suspended solids. The aim is to compare electrochemical treatment to conventional ETP methods and reduce treatment costs.
Decolorization of mixture of dyes: A critical reviewGJESM Publication
Water plays a vital and essential role in our ecosystem. This natural resource is becoming scarce, making
its availability a major social and economic concern. Use of a large variety of synthetic dyes in textile industries has raised an hazardous environmental alert. About 17 - 20% of freshwater pollution is caused by textile effluents. These effluents are recalcitrant to biodegradation and cause acute toxicity to the receiving water bodies, as these comprised of various types of toxic dyes, which are difficult to remove. Decolorisation of textile wastewater is therefore important before releasing it into the nearby local waterways. It therefore becomes essential to degrade the toxic chemicals of textile wastewater, so as to avoid the hazardous environmental effects. Several treatment methods have been employed to embark upon the problem of dye removal but degradation becomes further more difficult for effluents containing dye matrix. The
review study has been an attempt to present the different diversified attempts used for decolorisation of a mixture of dyes.
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.
This document discusses various methods for removing color from textile effluents, which is an environmental concern. It covers physical methods like membrane filtration and adsorption. Chemical methods include coagulation and advanced oxidation processes, though they produce sludge. Biological methods like fungal and microbial degradation are most economical. Specifically, phytoremediation uses plants to uptake and degrade dyes, while photodegradation employs TiO2 and radiation like sunlight to break down dyes. Plant surface morphology impacts accumulation and different plant types may work best for specific dyes.
The document describes an experiment to study the adsorption of Congo Red dye from aqueous solutions using pine bark as an adsorbent. Batch experiments were conducted by varying adsorbent dosage, initial dye concentration, pH, contact time and temperature. The effects of these parameters on dye removal efficiency were analyzed. Equilibrium adsorption isotherms and kinetic models were applied to the experimental data to understand the adsorption mechanism. The overall aim was to determine the efficiency of pine bark for removing toxic Congo Red dye from wastewater.
This document discusses the estimation of sterol content in various edible oils and ghee samples. Sterols were estimated using a UV spectrophotometer and the Liberman-Burchard reaction, which produces a green color with sterols. The sterol contents were determined to be highest in gingelly oil (84 mg/gm) and lowest in coconut oil (13 mg/gm). Sterol contents of various ghee samples ranged from 23-30 mg/gm. In conclusion, foods with higher sterol contents like gingelly oil can increase cholesterol levels and risk of heart disease, while a vegetarian diet is associated with lower cholesterol levels.
This document discusses several common insecticides used to control mosquitoes and other insects, including their chemical composition, physical properties, mode of action, effective dosage, and period of effectiveness. The insecticides described are DDT, Abate, Malathion, Fenthion, Mineral Oil, Pyrethrum, BHC, Paris Green, and Diazinon.
This document summarizes Wong Shi Ting's research project on the biosorption of the dye methylene blue using sugarcane bagasse. The research aims to characterize sugarcane bagasse using FTIR spectroscopy, study the factors affecting dye adsorption using two-level factorial design and response surface methodology, and determine the optimum adsorption conditions. Key findings include sugarcane bagasse having an adsorption capacity of 26.58 mg/g for methylene blue under optimal conditions identified by RSM. FTIR analysis also confirmed electrostatic interactions between the dye and sugarcane bagasse fibers during adsorption.
The document summarizes research on extracting rotenone from Derris elliptica roots. It discusses the plant's background and uses of rotenone. The study aims to optimize extraction parameters like solvent, particle size and ratio to maximize rotenone yield and content. Experiments use a central composite design and response surface methodology to identify significant factors. Rotenone concentration is determined using HPLC while biological activity is assessed via brine shrimp lethality assays. Statistical analysis of the results helps evaluate the effects of different extraction parameters.
An Experimental Investigation on Treatment of Tannery Effluent Using Azadirac...IJEAB
A preliminary investigation was carried out for the feasibile use of Azadirachta indica leafs powder as a natural coagulant to the treatment of tannery effluent. In this paper, Azadirachta indica leafs powder of 1, 2, 3 and 4mg/L dosages were used. Floc formation in coagulation process had been studied in the laboratory scale to determine the optimum dosage of natural coagulant. The above dosages were used in pre-treated tannery effluent with coagulants were considered to evaluate the percentage removal efficiency on the major pollutants of concern in in tannery effluent such as turbidity, TSS, TDS, COD and BOD. From the observed results, dosage of 3 mg/L gives better removal efficiencies with respect to turbidity, TSS, TDS, COD and BOD and appears to be suitable for tannery effluent treatment, when compared with other dosages.
The document summarizes a study that investigated the effects of Strobilanthes crispus extract on lipid profiles, antioxidant status, and toxicity in hypercholesterolemic rabbits. Specific objectives were to determine the extract's effects on total cholesterol, triglycerides, LDL, HDL, lipid peroxidation, liver enzymes, and atherosclerotic lesions. Rabbits were fed one of four diets for 12 weeks: control, high-cholesterol, high-cholesterol with 0.2% extract, or high-cholesterol with simvastatin. Blood and tissue samples were analyzed for biomarkers.
The document discusses nanoemulsions, which are liquid dispersions of two immiscible liquids (oil and water) with droplet sizes typically between 5-100 nm. Nanoemulsions can be oil-in-water, water-in-oil, or bi-continuous. They are thermodynamically stable and increase drug absorption. The key components are an oil phase, surfactants, and sometimes co-surfactants. Methods to prepare nanoemulsions include high-pressure homogenization, microfluidization, and ultrasonication. Nanoemulsions show potential for various applications like parenteral, topical, ocular, cosmetic, transdermal, and biotechnology uses due to
Formulation and Evaluation of W/O/W Multiple Emulsions with Diclofenac SodiumSagar Savale
Multiple emulsion is novel approach of drug delivery system
for enhancement of bioavailability and pharmacological
activity. It is important to prevent the problem of oral drug
delivery system and they are stabilized by using of combination
of hydrophilic and lipophilic surfactant. The specific ratio of
surfactant concentration is responsible for maintaining the
stability of multiple emulsions, the importance of this study was
to prepare multiple emulsion of Diclofenac sodium by using
two step emulsification process, by using the non-ionic
surfactant units. In multiple emulsion, the stability of multiple
emulsion was evaluated, percent entrapment efficiency as well
as in vitro studies are conducted. The process of primary and
secondary emulsification was optimized to get the stable
multiple emulsion with the high entrapment efficiency. Multiple
emulsion to improve bioavailability with the hypothesis that
improvement of drug release profile will reflect the
enhancement of bioavailability of the drug.
1. The document discusses supercritical carbon dioxide (CO2) dyeing as an alternative to conventional water-based dyeing.
2. Supercritical CO2 dyeing eliminates the use of water, chemicals, and auxiliaries in the dyeing process. It also reduces energy requirements compared to conventional dyeing.
3. The key advantages are that it produces no wastewater, reduces costs, and is more environmentally friendly than conventional dyeing.
Adsorption of Methylene blue and Malachite Green in Aqueous Solution using Ja...IJEAB
The adsorption of mixture of two basic dyes methylene blue and malachite green in aqueous solution onto jack fruit leaf ash in a batch system with respect to initial dye concentrations, pH, contact time, shaker speed and adsorbent doses was investigated.. The pseudo-first-order and pseudo-second- order kinetics model were used to describe the kinetic data. The rate constants at different pH values (3-9.1) were evaluated. The experimental data fitted well with the pseudo-second-order kinetic model. Equilibrium isotherms were analyzed by Langmuir, Freundlich and Temkin isotherm models. Maximum adsorption capacity was 20.41mg/g was achieved by Langmuir isotherm model. Error analysis was done to find the best model that described the experimental data well and it was the Langmuir model. The result indicated that jack fruit leaf ash could be fruitfully employed as low cost adsorbent for the removal of mixture of two basic dyes MB and MG from the wastewater.
Comparative Study for Adsorptive Removal of Coralene Blue BGFS Dye from Aqueo...IJERA Editor
Textile industries represent biggest impact on the environment due to high water consumption and waste water discharge as government control water pollution by setting strength regulation for waste water discharge, removal of color from waste water becomes more and more essential and attractive. Adsorption technology is very efficient in treatment of textile effluent. In this paper comparison of adsorption phenomena of textile dye Anthraquinone blue onto two different adsorbents MgO nano powder and Fe2O3 amorphous powder has been studied for removal of said dye from aqueous solutions. The adsorption of Anthraquinone blue on adsorbents occurs by studying the effects of adsorbent amount, dye concentration, contact time and pH of solution. All results found that MgO nano powder and Fe2O3 provide a fairly high dye adsorption capacity, which combined with their fulfilment of pollution control board’s standards, lack of pollution, lower environmental hazard and low-cost makes them promising for future applications. The present work also provides information on optimum value of different operating parameter for dye removal by two adsorbent.
ADSORPTION OF CONGO RED DYE AND METHYLENE BLUE DYE USING ORANGE PEEL AS AN A...Ajay Singh
This document discusses dyes and their adsorption using orange peel extract. It provides information on types of dyes and their harmful effects on wastewater. The document then describes an experiment where Congo red dye and methylene blue dye were adsorbed using orange peel extract over different time intervals. The percentage removal of Congo red dye was highest (23.25%) at 100 minutes, while methylene blue dye reached the highest removal rate (11.25%) at 20 minutes. In conclusion, the percentage dye removal increased with contact time and further experiments could explore additional dyes and adsorbents.
This document discusses using bagasse ash, a byproduct of sugar production, to treat industrial wastewater. It provides background on wastewater treatment technologies like biological, chemical, and physical methods. Adsorption using activated carbon from bagasse ash is proposed, which could remove 89% of acid orange dye from water. Producing activated carbon from a low-cost agricultural byproduct like bagasse ash makes it three times cheaper than conventional activated carbon. Further studies on column tests and regeneration are needed before commercializing bagasse ash activated carbon for industrial wastewater treatment.
Project report on Textile effluent treatment by electrochemical processBrijmohan Sharma
This document provides an overview of a student project on treating textile effluent water using an electrochemical process. It includes a certificate verifying the students conducted the project, an acknowledgements section thanking those who helped with the project, and a preface describing how the project helped the students learn. The contents section outlines the document, which explores using electrochemical treatment to make textile wastewater safer before discharge by reducing parameters like BOD, COD and suspended solids. The aim is to compare electrochemical treatment to conventional ETP methods and reduce treatment costs.
Decolorization of mixture of dyes: A critical reviewGJESM Publication
Water plays a vital and essential role in our ecosystem. This natural resource is becoming scarce, making
its availability a major social and economic concern. Use of a large variety of synthetic dyes in textile industries has raised an hazardous environmental alert. About 17 - 20% of freshwater pollution is caused by textile effluents. These effluents are recalcitrant to biodegradation and cause acute toxicity to the receiving water bodies, as these comprised of various types of toxic dyes, which are difficult to remove. Decolorisation of textile wastewater is therefore important before releasing it into the nearby local waterways. It therefore becomes essential to degrade the toxic chemicals of textile wastewater, so as to avoid the hazardous environmental effects. Several treatment methods have been employed to embark upon the problem of dye removal but degradation becomes further more difficult for effluents containing dye matrix. The
review study has been an attempt to present the different diversified attempts used for decolorisation of a mixture of dyes.
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.
This document discusses various methods for removing color from textile effluents, which is an environmental concern. It covers physical methods like membrane filtration and adsorption. Chemical methods include coagulation and advanced oxidation processes, though they produce sludge. Biological methods like fungal and microbial degradation are most economical. Specifically, phytoremediation uses plants to uptake and degrade dyes, while photodegradation employs TiO2 and radiation like sunlight to break down dyes. Plant surface morphology impacts accumulation and different plant types may work best for specific dyes.
The document describes an experiment to study the adsorption of Congo Red dye from aqueous solutions using pine bark as an adsorbent. Batch experiments were conducted by varying adsorbent dosage, initial dye concentration, pH, contact time and temperature. The effects of these parameters on dye removal efficiency were analyzed. Equilibrium adsorption isotherms and kinetic models were applied to the experimental data to understand the adsorption mechanism. The overall aim was to determine the efficiency of pine bark for removing toxic Congo Red dye from wastewater.
This document discusses the estimation of sterol content in various edible oils and ghee samples. Sterols were estimated using a UV spectrophotometer and the Liberman-Burchard reaction, which produces a green color with sterols. The sterol contents were determined to be highest in gingelly oil (84 mg/gm) and lowest in coconut oil (13 mg/gm). Sterol contents of various ghee samples ranged from 23-30 mg/gm. In conclusion, foods with higher sterol contents like gingelly oil can increase cholesterol levels and risk of heart disease, while a vegetarian diet is associated with lower cholesterol levels.
This document discusses several common insecticides used to control mosquitoes and other insects, including their chemical composition, physical properties, mode of action, effective dosage, and period of effectiveness. The insecticides described are DDT, Abate, Malathion, Fenthion, Mineral Oil, Pyrethrum, BHC, Paris Green, and Diazinon.
This document summarizes Wong Shi Ting's research project on the biosorption of the dye methylene blue using sugarcane bagasse. The research aims to characterize sugarcane bagasse using FTIR spectroscopy, study the factors affecting dye adsorption using two-level factorial design and response surface methodology, and determine the optimum adsorption conditions. Key findings include sugarcane bagasse having an adsorption capacity of 26.58 mg/g for methylene blue under optimal conditions identified by RSM. FTIR analysis also confirmed electrostatic interactions between the dye and sugarcane bagasse fibers during adsorption.
The document summarizes research on extracting rotenone from Derris elliptica roots. It discusses the plant's background and uses of rotenone. The study aims to optimize extraction parameters like solvent, particle size and ratio to maximize rotenone yield and content. Experiments use a central composite design and response surface methodology to identify significant factors. Rotenone concentration is determined using HPLC while biological activity is assessed via brine shrimp lethality assays. Statistical analysis of the results helps evaluate the effects of different extraction parameters.
An Experimental Investigation on Treatment of Tannery Effluent Using Azadirac...IJEAB
A preliminary investigation was carried out for the feasibile use of Azadirachta indica leafs powder as a natural coagulant to the treatment of tannery effluent. In this paper, Azadirachta indica leafs powder of 1, 2, 3 and 4mg/L dosages were used. Floc formation in coagulation process had been studied in the laboratory scale to determine the optimum dosage of natural coagulant. The above dosages were used in pre-treated tannery effluent with coagulants were considered to evaluate the percentage removal efficiency on the major pollutants of concern in in tannery effluent such as turbidity, TSS, TDS, COD and BOD. From the observed results, dosage of 3 mg/L gives better removal efficiencies with respect to turbidity, TSS, TDS, COD and BOD and appears to be suitable for tannery effluent treatment, when compared with other dosages.
The document summarizes a study that investigated the effects of Strobilanthes crispus extract on lipid profiles, antioxidant status, and toxicity in hypercholesterolemic rabbits. Specific objectives were to determine the extract's effects on total cholesterol, triglycerides, LDL, HDL, lipid peroxidation, liver enzymes, and atherosclerotic lesions. Rabbits were fed one of four diets for 12 weeks: control, high-cholesterol, high-cholesterol with 0.2% extract, or high-cholesterol with simvastatin. Blood and tissue samples were analyzed for biomarkers.
The document discusses nanoemulsions, which are liquid dispersions of two immiscible liquids (oil and water) with droplet sizes typically between 5-100 nm. Nanoemulsions can be oil-in-water, water-in-oil, or bi-continuous. They are thermodynamically stable and increase drug absorption. The key components are an oil phase, surfactants, and sometimes co-surfactants. Methods to prepare nanoemulsions include high-pressure homogenization, microfluidization, and ultrasonication. Nanoemulsions show potential for various applications like parenteral, topical, ocular, cosmetic, transdermal, and biotechnology uses due to
Formulation and Evaluation of W/O/W Multiple Emulsions with Diclofenac SodiumSagar Savale
Multiple emulsion is novel approach of drug delivery system
for enhancement of bioavailability and pharmacological
activity. It is important to prevent the problem of oral drug
delivery system and they are stabilized by using of combination
of hydrophilic and lipophilic surfactant. The specific ratio of
surfactant concentration is responsible for maintaining the
stability of multiple emulsions, the importance of this study was
to prepare multiple emulsion of Diclofenac sodium by using
two step emulsification process, by using the non-ionic
surfactant units. In multiple emulsion, the stability of multiple
emulsion was evaluated, percent entrapment efficiency as well
as in vitro studies are conducted. The process of primary and
secondary emulsification was optimized to get the stable
multiple emulsion with the high entrapment efficiency. Multiple
emulsion to improve bioavailability with the hypothesis that
improvement of drug release profile will reflect the
enhancement of bioavailability of the drug.
Nanoemulsion Characterisation Techniques and Formulation Methodsijtsrd
Nanoemulsions are thermodynamically stable colloidal dispersion systems made up of two immiscible liquids combined with emulsifying agents surfactants and co surfactants to produce a single phase. Nanoemulsions have been studied extensively as drug delivery devices. This review attempts to bring together information on the many nanoemulsion formulation and characterization techniques that have been developed. The persuasion approach and the Brute force method are two methods for creating nanoemulsions. Entrapment efficiency, particle size, polydispersity index, zeta potential, and characterization using differential scanning calorimetry, Fourier transform infrared spectroscopy, and transmission electron microscopy are just a few of the techniques used to characterise nanoemulsions. In vitro drug release, in vitro permeation, stability and thermodynamic stability, shelf life, dispersibility, viscosity, surface tension, friccohesity, refractive index, transmittance, pH, and osmolarity are all used to assess nanoemulsions. Rohit Ghogare | Prof. Santosh Waghmare | Dr. Hemant Kamble "Nanoemulsion- Characterisation Techniques and Formulation Methods" Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-6 | Issue-3 , April 2022, URL: https://www.ijtsrd.com/papers/ijtsrd49586.pdf Paper URL: https://www.ijtsrd.com/pharmacy/other/49586/nanoemulsion-characterisation-techniques-and-formulation-methods/rohit-ghogare
This webinar covered the industrial approach to organic chemistry and introductions to HPLC and dissolution testing. On the first day, Mr. Sandip Patel discussed automated HPLC methods and dissolution testing techniques. The second day, Dr. Janmejay Dave spoke about research and development in the pharmaceutical industry, including intermediate synthesis and the regulatory process for drug approval. Attendees learned about applying organic chemistry principles at scale in industry and analytical tools like HPLC and dissolution testing that are important for product development and quality control.
Cucurbita pepo oil as a drug microemulsion formulation: study of phase diagramNanomedicine Journal (NMJ)
Abstract
Objective(s):
Investigation of phase diagram of various drug formulations is effective to predict different phase region of drugs to detect final formula. The purpose of this research was to develop the ternary phase diagrams for a drug microemulsion system consisting of Cucurbita pepo (pumpkin) oil, surfactant (Tween 80) and deionized water.
Materials and Methods:
An electrical conductivity was used to study the properties of system. Particle size analysis of microemulsion system was performed by dynamic light scattering.
Results:
The electrical conductivity of the microemulsions increases with increasing of aqueous phase content. Structural transitions from the oil-in-water to a bi-continuous phase then inversion to water-in-oil occured in the system. Diameter of particles was calculated 70 nm (for 75 percent of particles) and 35 nm (for 25 percent of particles). Solubility results showed that microemulsion system of Cucurbita pepo oil can increase its solubility in aqueous medium due to droplet size reduction into nanometer size.
Conclusion:
Microemulsion technique can be used as a successful method in preparation of Cucurbita pepo oil drug formulation.
Nanoemulsion formation, stability and applicationsAshish Gadhave
This document summarizes nanoemulsions, which are kinetically stable emulsions with droplet sizes between 20-200 nm. It discusses their formation using high-energy methods like high-pressure homogenization and ultrasound, as well as low-energy methods like phase inversion temperature. The main instability mechanism for nanoemulsions is Ostwald ripening, where smaller droplets dissolve into a continuous phase. Applications described include use in pharmaceuticals for ocular, nasal, and other drug delivery due to improved absorption and stability compared to traditional emulsions. Nanoemulsion polymerization is also discussed as a technological application.
Development and method validation for determination of Deltamethrin residue i...IOSR Journals
Olive oil is the most important commodities produced in the Mediterranean region. Due to its significant economical importance, the usage of pesticides in its production is systematic, by using a wide range of plant protection products with a variety of modes of action. As a consequence, monitoring of their residue levels in these products is a necessity. In the present study a reversed-phase high performance liquid chromatography method, with a short sample preparation step, based on acetonitrile extraction is developed and validated in olive oil, with a large scope that includes Deltamethrin as pesticide. Good sensitivity and selectivity of the method were obtained with limits of quantification at 0.2 mg kg-1. Deltamethrin has recovery rate which is of about 80℅. We confirm also the efficiency of alumina, used as adsorbent in the clean up step, to remove triglycerides and to get a pure extract. The agronomic implementation of this protocol allows us to determine the influence of some parameters on the dose and the period of treatment affecting the detected quantities of Deltamethrin residues in the produced olive oil. Indeed, we prove that the treatment dose should be specific for each case considering the olive variety, the geography of the orchard, and the predicted harvest time to determine the convenient dose of treatment. In addition, the results show that the preventive treatment at the blooming phase, does not lead to the concentration of Deltamethrin residues in the oil as it happens at the lipogenesis phase.
Formulation and in vitro evaluation of Vincristine microemulsion by using nig...SriramNagarajan18
1. The study formulated microemulsions of vincristine using nigella sativa oil to improve its solubility and oral bioavailability.
2. Microemulsions were prepared using the phase titration method with nigella sativa oil, Tween 80, Tween 20 and water. Eight blank formulations were developed based on physical parameters and three were selected for drug loading.
3. The particle size, drug content, in vitro dissolution and ex vivo diffusion of the formulations were evaluated. The optimized formulation showed sustained release of vincristine permeating through goat skin membrane, indicating improved oral delivery potential.
The document describes several extraction techniques including counter-current extraction, supercritical fluid extraction, solid-phase extraction, microwave-assisted extraction, ultrasound extraction, and the phytonics process. Counter-current extraction uses solvent flowing in the opposite direction of plant material to efficiently extract compounds. Supercritical fluid extraction uses substances like carbon dioxide in supercritical states for non-toxic extractions. The techniques find various applications in food, fragrance, essential oil, and pharmaceutical extractions.
This document discusses nanoemulsions and their use as drug delivery systems. It begins with an introduction that defines nanoemulsions as thermodynamically stable mixtures of oil, water and surfactant with droplet sizes between 50-500nm. It then covers the classification, advantages, limitations and methods of preparing nanoemulsions. The document discusses characterizing techniques and various applications of nanoemulsions for drug delivery, including parenteral, intranasal, ocular, tumor targeting, pulmonary and oral routes. In conclusion, nanoemulsions can increase drug solubility, bioavailability and targeting potential for various therapeutic applications.
This document summarizes research on treating wastewater from the cosmetics industry. It finds that cosmetic wastewater contains various organic and inorganic compounds that can be toxic, including surfactants, fragrances, and UV filters. The document reviews different treatment methods studied, finding the best results were achieved using catalytic oxidation which reduced COD by around 80%. The authors' own research found coagulation using FeCl3 at pH 6 and a flocculant reduced COD by 63.9%, while a Fenton process reduced it by 31.1-54.9%. Overall, pretreatment methods like coagulation and advanced oxidation processes can help remove contaminants before biological treatment.
Self-nanoemulsifying drug delivery system (SNEDDS) of Amomum compactum essent...UniversitasGadjahMada
This document summarizes research on the development of a self-nanoemulsifying drug delivery system (SNEDDS) for Amomum compactum essential oil. Key points:
- Virgin coconut oil was selected as the carrier oil due to its high solubility of the essential oil compared to other oils tested.
- A D-optimal mixture design was used to optimize the SNEDDS formulation, with emulsification time and transmittance as the response variables.
- The optimized formulation contained 10% Amomum compactum essential oil, 10% virgin coconut oil, 65.71% Tween 80 surfactant, and 14.29% PEG 400 co-surfactant.
1) The study investigated the antimicrobial properties of fatty acid methyl esters (FAME) extracted from the marine microalgae Nannochloropsis oculata.
2) FAME were produced through transesterification and tested against various bacteria and yeast. Results showed that FAME were more effective against gram-negative bacteria than gram-positive bacteria and yeast.
3) Gas chromatography-mass spectrometry analysis revealed that the dominant fatty acids in N. oculata oil were palmitic acid, oleic acid, and arachidic acid. DNA inhibition assays further confirmed the bactericidal effects of FAME.
Rahul Molla's document discusses recent advances in nanosponges as a drug delivery system. Nanosponges are porous polymeric particles that can be used for controlled drug delivery through various routes of administration including topical, oral, and parenteral. The document outlines the advantages of nanosponges such as increased drug solubility and controlled release as well as factors that influence nanosponge formulation and common preparation methods. Evaluation techniques for nanosponges including particle size, drug loading efficiency, and in vitro drug release are also summarized. Finally, the document discusses applications of nanosponges in cancer therapy, topical drug delivery, and antiviral delivery.
New Screening Protocol for Effective Green Solvents Selection of Benzamide, S...Maciej Przybyłek
New protocol for screening efficient and environmentally friendly solvents was proposed and experimentally verified. The guidance for solvent selection comes from computed solubility via COSMO-RS approach. Furthermore, solute-solvent affinities computed using advanced quantum chemistry level were used as a rationale for observed solvents ranking. The screening protocol pointed out that 4-formylomorpholine (4FM) is an attractive solubilizer compared to commonly used aprotic solvents such as DMSO and DMF. This was tested experimentally by measuring the solubility of the title compounds in aqueous binary mixtures in the temperature range between 298.15 K and 313.15 K. Additional measurements were also performed for aqueous binary mixtures of DMSO and DMF. It has been found that the solubility of studied aromatic amides is very high and quite similar in all three aprotic solvents. For most aqueous binary mixtures, a significant decrease in solubility with a decrease in the organic fraction is observed, indicating that all systems can be regarded as efficient solvent-anti-solvent pairs. In the case of salicylamide dissolved in aqueous-4FM binary mixtures, a strong synergistic effect has been found leading to the highest solubility for 0.6 mole fraction of 4-FM.
The aim of the investigation was to evaluate the anti-bacterial, bioactive compounds and anti-oxidant property of fibrous brown marine algae Sargassum wightii. Antimicrobial finish has been imparted to the cotton fabric using extracts of seaweed by microencapsulation using pad-dry-cure method. Both in vitro and in vivo studies have demonstrated, how this Sargassum wightti acts as antioxidant, and antibacterial properties and it also shows good antiviral and anti-carcinogenic activities. Bioactive compounds are inhibited the growth of microorganisms present in human body. Bioactive compounds were confirmed by means of the spectrum in the GC-MS spectroscopy. Antioxidant activities were evaluated using the DPPH method. The total phenolic content was determined with the folin-ciocalteu method. The methanol fraction of treated fabric had the highest antioxidant activity (42.5+1.21%), because of the phenolic content trap the reactive oxygen species and develops the cells present in the skin. Parallel streak method was to evaluate the antibacterial activity of seaweed treated fabric. The results showed that higher inhibition zone of 40 mm. The treated fabrics are most widely used in a wide range of health care, pharmaceutical and hygienic textiles.
This document discusses criteria for selecting detergents for use in biochemistry experiments. It provides an overview of different types of detergents, including their classification based on chemical structure and properties like critical micellar concentration. When choosing a detergent, factors like temperature, pH, ionic strength and potential interference with assays must be considered. Integral membrane proteins often require the presence of detergent to stabilize them outside of the lipid bilayer environment. Nonionic detergents are generally less denaturing than ionic detergents for investigating membrane protein structure. The document recommends testing a set of detergents to select the one best able to preserve a protein's structural and functional state for the specific application.
The document discusses new technologies and product development in the dairy industry, focusing on membrane processing techniques. It describes how membrane processes like reverse osmosis, nanofiltration, ultrafiltration and microfiltration are being used for applications like concentration and fractionation of fluid milk and whey. These techniques offer advantages over conventional processes like avoidance of heat-related changes and more efficient energy usage. The document also discusses other emerging technologies like UHT processing and how various membrane modules and configurations are being implemented.
This document describes a study that used response surface methodology to optimize the solvent system for recovering the biopolymer pullulan from fermentation broth. Four solvents (ethanol, acetone, isopropanol, tetrahydrofuran) were selected and their interactions studied using a 20-experiment D-optimal design. The results identified a solvent system with lower ethanol that recovered 1.44 times more pullulan than conventional methods. Statistical analysis generated a model to understand the solvent interactions and identify compositions giving higher pullulan yields, enhancing downstream processing efficiency.
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Clove oil nanoemulsion as an effective
antibacterial agent: Taguchi optimization method
Mohammad Hassan Shahavi, Morteza Hosseini, Mohsen Jahanshahi, Rikke
Louise Meyer & Ghasem Najafpour Darzi
To cite this article: Mohammad Hassan Shahavi, Morteza Hosseini, Mohsen Jahanshahi,
Rikke Louise Meyer & Ghasem Najafpour Darzi (2015): Clove oil nanoemulsion as an effective
antibacterial agent: Taguchi optimization method, Desalination and Water Treatment, DOI:
10.1080/19443994.2015.1092893
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2. Clove oil nanoemulsion as an effective antibacterial agent: Taguchi
optimization method
Mohammad Hassan Shahavia,b
, Morteza Hosseinia,
*, Mohsen Jahanshahia
,
Rikke Louise Meyerb
, Ghasem Najafpour Darzia,
*
a
Faculty of Chemical Engineering, Nanotechnology Research Institute, Babol Noshirvani University of Technology, Babol, Iran,
emails: m_shahavi@yahoo.com, shahavi@inano.au.dk (M.H. Shahavi), m.hosseini@nit.ac.ir (M. Hosseini), mmohse@yahoo.com,
mjahan@nit.ac.ir (M. Jahanshahi), Tel. +98 11 3233 4204; Fax: +98 11 3231 0975; emails: najafpour@nit.ac.ir,
najafpour8@gmail.com (G. Najafpour Darzi)
b
Interdisciplinary Nanoscience Center (iNANO), Aarhus University, Aarhus, Denmark, email: rikke.meyer@inano.au.dk (R.L. Meyer)
Received 26 May 2015; Accepted 23 August 2015
ABSTRACT
Clove oil is an essential oil used as a biodegradable antibacterial agent in food and pharma-
ceutical products. Emulsions are used to stabilize and increase the antimicrobial efficacy of
oils in aqueous solutions. Smaller droplets provide better distribution of the oil. In this
study, we formulate clove oil in aqueous solution by nanoemulsion. The aim of this study
was to optimize key parameters in the preparation of clove oil nanoemulsion to obtain
stable emulsions with less than 50 nm droplet size. The evaluated parameters include the
concentration of clove oil, concentration of emulsifier, hydrophilic–lipophilic balance (HLB)
number, and ultrasonication time. We determined the following response parameters: dro-
plet size, polydispersity index, and zeta potential, and we aimed to achieve <50 nm droplet
size with low polydispersity index and a highly negative zeta potential. The optimization
and evaluation was obtained via Taguchi method. Taguchi method identified the concentra-
tion of clove oil and the HLB as the most affecting factors in the preparation of nanoemul-
sions. The optimum conditions for the preparation of nanoemuslion such as mean droplet
size, polydispersity index, and zeta potential were 50 nm, 0.49 and −40.7 mV, respectively.
This formulation of clove oil resulted in minimum inhibitory concentration against
Escherichia coli and Bacillus cereus of 16 and 32 μg/ml, respectively, and minimal bactericidal
concentrations of 16 and 64 μg/ml, respectively.
Keywords: Antibacterial; Clove oil; Droplet size; Nanoemulsion; Taguchi optimization
1. Introduction
Nowadays, environmental pollutions caused by
excessive use of pesticides have brought scientists and
public special attention. Applications of effective green
pesticides in agricultural production fields are highly
recommended to prevent crop yield losses and obtain
high production yield. Synthetic chemicals used as
pesticides may cause serious side effect, such as pene-
tration of hazardous chemical into surface water bod-
ies and create environmental complication due to
toxicity of chemicals used [1,2].
*Corresponding authors.
1944-3994/1944-3986 Ó 2015 Balaban Desalination Publications. All rights reserved.
Desalination and Water Treatment (2015) 1–12
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doi: 10.1080/19443994.2015.1092893
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3. Nanoemulsions are one of the emulsion types that
can be prepared from oil, water, and emulsifier with
particle sizes ranged in 10–100 nm [3]. The biggest dif-
ference between nano and conventional emulsions is
the size of droplets. Nanoemulsion possesses several
advantages, such as high physical stability (stability to
gravitational forces, flocculation and coalescence), high
bioavailability, and low turbidity, which make them
more attractive systems for food applications [4–6],
cosmetics [7], and pharmaceuticals [8]. Apart from
droplet size, coalescence also depends on other envi-
ronmental factors, such as the type of emulsifiers used
(ionic/nonionic), pH, and storage temperature. Gener-
ally, oil in water nanoemulsions acts as a carrier of
bioactive compounds for instance essential oil (dis-
persed phase) in water (continuous phase). Essential
oils are potential sources of novel antimicrobial com-
pounds; especially used against pathogenic bacteria
[9]. Generally, nanoemulsion of natural oil in water
cannot be easily separated from aqueous phase [10].
Therefore, they can be formulated with different
bioactive agents, such as drugs in pharmaceutical
industry [5], as a flavor [11], solubilizing agent, water-
insoluble compounds in agrochemical industry [5,12],
lotion for skincare in cosmetics [7] and also used as
antimicrobial agents in food industry [13].
Clove oil has biological activities, such as
antibacterial, antifungal, insecticidal, and antioxidant
properties. It is traditionally used as a flavor and
antimicrobial agent in food [13,14]. Eugenol is the
major constituent of clove essential oil; it is a phenolic
compound with strong biological and antimicrobial
activities. It can denature protein and react with phos-
pholipids in cell membrane. Also, it can change cell
membrane permeability and inhibit a great number of
Gram-negative and Gram-positive bacteria as well as
various types of yeast [15,16].
Ultrasonic emulsification is an energy-efficient
method to develop nanoemulsions. This method is
documented as a fast and efficient technique for
formulating stable nanoemulsions with very small
droplet size and low polydispersity [8,17]. It takes
advantage of sound waves to generate powerful shock
waves and create acoustic cavitation to disrupt the
coarse droplets with the aid of an ultrasonic probe
homogenizer [4,8,18]. This method is preferable over
mechanical methods due to its lower energy consump-
tion (through heat loss) and use of small amounts of
emulsifiers. Ultrasonic emulsions have more uniform
droplet size and are more stable compared to emul-
sions achieved by mechanical agitation [18–20].
Taguchi design method is a fractional factorial
design which uses an orthogonal array (OA) that can
greatly reduce the number of experiments [21]. In
addition, analysis of variance (ANOVA) can estimate
the effect of a factor on the characteristic properties.
The variability is decisive for choosing the optimal
condition. Our aim is to determine the smallest dro-
plet size with high stability. The variability is
expressed by signal-to-noise (S/N) ratio. This is an
important factor to simulate and analyze the influence
of multiple control factors on performance as well as
to investigate the influence of individual factors to
determine the most effective parameters [22].
The nanoemulsion clove oil droplet size of less
than 50 nm was not reported [23,24]. The objective of
present work was to optimize process parameters in
the preparation of clove oil nanoemulsion by means of
oil and emulsifier concentrations, sonication time, and
hydrophilic–lipophilic balance (HLB) number. The
clove oil nanoemulsion was tested as antibacterial
agent against Escherichia coli and Bacillus cereus.
2. Materials and methods
2.1. Materials
Clove oil (C8392) was purchased from Sigma–
Aldrich®
(St. Louis, MO, USA); the nonionic surfac-
tants of polyethylene sorbitan monooleate (822187,
Tween®
80) synthetic grade and sorbitan monooleate
(840123, Span®
80) synthetic grade were purchased
from Merck-Millipore®
(Darmstadt, Germany); water
used in all the experiments was purified with a Milli-
Q system consisting of filtration through 0.2 μm filters
(Milipore Co., Bedford, MA, USA). For antibacterial
testing; microbiological grade of peptone from casein
(70171), peptone from soybean (70178), and agar pow-
der (05040) were purchased from Fluka®
Analytical
(Dresden, Germany). In addition, dipotassium hydro-
gen phosphate (60353) and sodium chloride (S9888)
were supplied from Sigma–Aldrich®
(St. Louis, MO,
USA). D (+)-glucose (108337) was obtained from
Merck-Millipore®
(Darmstadt, Germany).
2.2. Antimicrobial activity assay
Gram-negative bacteria, E. coli K12 (LZB035; Kent,
UK) and Gram-positive bacteria, B. cereus (ATCC
10987) were maintained on tryptic soy agar (TSA)
plates and single colonies were inoculated and cul-
tured overnight in tryptic soy broth (TSB) (17 g/l pep-
tone–casein, 3 g/l peptone–soybean, 2.5 g/l
dipotassium hydrogen phosphate, 2.5 g/l glucose, and
5 g/l sodium chloride) at 37˚C and agitated at
120 rpm. Trypticase soy agar (TSA plate) was used as
solid culture with 1.5% agar added to the TSB media
and then plates were stored at 4˚C.
2 M.H. Shahavi et al. / Desalination and Water Treatment
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4. The estimation of the minimal inhibitory concen-
tration (MIC) and minimal bactericidal concentration
(MBC) of optimum formula of clove oil nanoemulsion
were measured by the broth microdilution method.
Briefly, overnight cultures were diluted in fresh TSB
to 107
CFU/ml, and diluted 10-fold into 200 μl TSB in
sterile 96-well microtiter plates (NUN-161093, Nun-
clon™) prepared with a concentration of the clove oil
nanoemulsion ranging from 1 to 1,024 μg/ml after
addition of the inoculum to the wells. Nanoemulsion-
free wells served as positive controls (growth control)
and bacteria-free well served as blanks. Microtiter
plates were then incubated statically at 37˚C for 24 h,
and then optical density at 600 nm (OD600) was deter-
mined using a microtiter plate reader (Power Wave™
XS2; BioTek®
, Vermont, USA). The MIC was defined
as the lowest concentration of the clove oil nanoemul-
sion at which an increase in OD600 compared to the
blanks could not be detected. The MBC was deter-
mined by transferring 10 μl of each suspension from
wells with no apparent growth to TSA and examining
growth after incubation at 37˚C for 24 h. The MBC
was defined as the lowest concentration of the clove
oil nanoemulsion resulting in no detection of viable
cells, corresponding to kill >99.99% of the bacteria.
Each experiment was replicated for four times.
2.3. HLB number
Nonionic surfactants consist of molecules that com-
bine both hydrophilic and lipophilic groups. They are
classified according to the balance of the size and
strength of these two opposing groups which is called
the HLB, and assigned a HLB number to each of these
molecules. In general, the HLB number is in a wide
range from 0 (hydrophobic end) to 20 (hydrophilic
end) such that high HLB surfactants are used for mak-
ing oil in water emulsions.
Tween®
80 (HLB value of 15.0) and Span®
80 (HLB
value of 4.3) as mixtures were selected for the
preparation of emulsions; because of their high degree
of compatibility with other ingredients, chemically
stable, and having low toxicity. Fig. 1 demonstrates
the hydrophilic and hydrophobic tails of Tween®
80
and Span®
80, respectively. Span®
80 as a viscous,
lipophilic, emulsifying liquid agent is often used to
form water in oil emulsions. Tween®
80, hydrophilic
in nature, is a derivative of Span®
80 due to hydroxyl
functional groups on sorbitan ring are replaced by the
bulky polyoxyethylene groups. Such substitutions
make Tween®
80 more soluble in water, which then
easily formed oil in water emulsions. Furthermore,
Tween®
80 and Span®
80 are generally considered as
safe additives in pharmaceutical, cosmetic, and food
products. Nonionic surfactants as uncharged mole-
cules are also known as safe and biocompatible prod-
ucts; they are not affected by pH changes in media
[25–27].
Use of single surfactant was tested, due to low or
high HLB values, and also based on zeta potential
data the droplets size was not quite stable. A blend of
hydrophilic and lipophilic surfactants is required to
obtain longer stability of the dispersion phase at the
lowest concentration levels. Also, a blend of surfac-
tants with an HLB that matches with the oil phase has
to provide high solubilization and stability of the dis-
persion system. Therefore, the selection of surfactant
blends at low and high HLB matches the HLB of oil
which is important in the formulation of a colloidal
system. In this research, the HLB number system was
used to optimize a compatible nonionic mixture of
surfactants and calculate the HLB number of mixed
surfactants system by the following expression:
HLB ¼
mA HLBA þ mB HLBB
mA þ mB
(1)
where mA (g) and mB (g) are the mass of the surfactants
A and B, respectively. HLBA and HLBB are the HLB
number of the surfactants A and B, respectively [28].
2.4. Taguchi design of the experiment
The Taguchi design method applies fractional
factorial test designs called OAs that serve to reduce
the number of experiments. The selection of a suitable
OA depends on the number of control factors and
their levels. Using OA design can estimate multiple
process variables which is simultaneously affecting on
the performance characteristic, while minimizing the
number of test runs. For example, for four parameters
at three levels, the traditional full factorial design
would require 34
or 81 experiments. In the Taguchi L9
OA, however, the required experiments are only 9. To
accomplish such goal, Taguchi L9 OA design (four
factors with 3-level design) was used to determine
and optimize the instrumental parameters to consider
very small droplet size diameter and long storage sta-
bility and small polydispersity. The design of experi-
ment (DOE) using the Taguchi method provides a
simple, efficient, and systematic approach to deter-
mine the optimum conditions [29–31].
2.4.1. Effective factors and levels
There are four key factors in the preparation of
clove oil nanoemulsion procedure which include the
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5. oil concentration (A), emulsifier concentration (B),
HLB number (C), and ultrasonic emulsification time
(D). These four factors, each at three levels, are
summarized in Table 1.
2.4.2. Selection of OA and factor assignments
In this research, L9 OA (four parameters, in three
levels) was used. To observe the data reliably on
experiment, droplet size (nm), polydispersity index
(PDI), and zeta potential (mV) data were repeated
three times with the same conditions. L9 OA was used
to determine the instrumental parameters shown in
Table 2. Each row in this table represents a trial
condition with the level of factors.
For analysis of the results and optimized condi-
tions for setting the control factors, QUALITEK-4
(QT4) software was used. QT4 Version 4.75 is the MS-
Windows 7 version software for automatic design and
analysis of Taguchi experiments.
2.4.3. Signal-to-noise ratio
In the Taguchi method “signal” and “noise” for
output characteristics and the signal/noise ratio (S/N)
represent the desirable signal value and the undesir-
able noise value, respectively. The ratio is used to
transform the quality characteristics [32]. The equation
of S/N ratio depends on the criteria used for
optimization of the quality characteristics. In this
research, the results of nanoemulsion of mean droplets
size, PDI, and zeta potential values were used to
calculate the corresponding S/N ratio, and the
equation is stated as follows:
S=N ¼ 10 log
1
n
X
Y2
(2)
where n is the number of tests and Y is the response
factor.
The S/N ratio mean values for samples at each set
of experimental conditions for each process parameter
variables are obtained. Based on the orthogonal
experimental design, the effect of each process
parameter on S/N ratio at different levels for each
sample is properly reported.
2.4.4. Statistical analysis
ANOVA was performed in order to determine sig-
nificant differences among the factors. It evaluates sig-
nificance of the controlling factors by calculating the
F-ratio (variance ratio) and the percentage contribution
by each of the design parameters and error. Sum of
squares (SS), degrees of freedom (DOF), mean of
square (MS), and associated F-test of significance (5%)
(F) can be calculated as follows:
SSA ¼
X
kA
i¼1
A2
i
nAi
!
T2
N
(3)
Fig. 1. Specification of surfactants.
Table 1
Selected process parameters and respective levels in the experimental design
Process parameters Level 1 Level 2 Level 3
(A) Clove oil concentration (wt%) 2.5 7.5 15.0
(B) Emulsifier concentration (wt%) 2.5 5.0 7.5
(C) Mixed HLB number 9.0 12.0 15.0
(D) Ultrasonication time (s) 150 300 450
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6. where kA is the number of the levels of factor A, nAi
is
the number of all observations at level i of factor A, Ai
is the sum of all observations of level i of factor A,
and T is the sum of all observations. SS of error is
computed by the following equation:
SSe ¼ SST SSA þ SSB þ
ð Þ (4)
where SST is the total SS:
SST ¼
X
N
i¼1
y2
i
T2
N
(5)
where yi is the observation of i. MS is calculated by
dividing the SS by the DOF. DOFA is estimated by
DOFA = kA − 1. F-value is calculated as follows:
FA ¼
MSA
MSe
(6)
MSe is the variance of error.
The percentage contribution for each factor is
defined as the portion of a total observed variance in
the experiment for each significant factor. The greater
the value the more it contributes to the final results.
Quantitative evaluation can be achieved using percent-
age contribution (P (%)). It is calculated by dividing the
source’s net variation by SST, which is given as follows:
P %
ð Þ ¼
SSA DOFA MSe
ð Þ
SST
100 (7)
2.5. Clove oil nanoemulsion
In order to obtain clove oil emulsion in nano dro-
plets size, the number of blends of different weight
percentages of Span®
80 (HLB = 4.3) and Tween®
80
(HLB = 15) for various HLB number on experimental
design were prepared. These variables were deter-
mined from Eq. (1) as indicated in Table 3. For exam-
ple, surfactant mixing ratio to obtain the HLB no. 9,
56 wt% of Span®
80 with 44 wt% of Tween®
80 were
mixed.
Based on Taguchi design, sample preparation with
different concentration of clove oil and surfactants
blended with Span®
80 and Tween®
80 (based on dif-
ferent blends summarized in Table 3) to Milli-Q water
as the aqueous phase in a test tube. Then, all samples
were premixed by vortex mixer IKA®
-MS2 Minishaker
(IKA Labortechnik, Staufen, Germany) for 1 min; fur-
ther emulsification by sonication was performed for 3
times using an ultrasonic homogenizer with a power
of 70 W at 20 kHz using Sonopuls HD 2070 (Bandelin
Electronic, Berlin, Germany) equipped with a 3-mm
diameter Sonotrode probe made of titanium. In order
to keep the temperature below 30˚C, the emulsions
were maintained in an iced water bath. Then the mean
droplet diameter, PDI, and zeta potential of all the
samples were determined. Fig. 2 presents the
schematic diagram of the experimental set up for
preparation of nanoemulsions.
Table 2
Experimental layout by Taguchi L9 OA design
Experimental run
number
Parameters
Clove oil concentration
(wt%)
Emulsifier concentration
(wt%)
Mixed HLB
number
Ultrasonication time
(s)
1 2.5 2.5 9.0 150
2 2.5 5.0 12.0 300
3 2.5 7.5 15.0 450
4 7.5 2.5 12.0 450
5 7.5 5.0 15.0 150
6 7.5 7.5 9.0 300
7 15.0 2.5 15.0 300
8 15.0 5.0 9.0 450
9 15.0 7.5 12.0 150
Table 3
Ratio of mixed surfactants in preparation of mixed HLB
number based on Eq. (1)
Mixed HLB number
9 12 15
HLBA(Span® 80) = 4.3 mA = 56 28 0
HLBB(Tween® 80) = 15 mB = 44 72 100
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7. 2.6. Droplet size and PDI analysis
One of the most important physical characteristics of
a nanoemulsion is the droplets size distribution.
Dynamic light scattering (DLS) with a Malvern Zeta-
sizer®
Nano ZS (model ZEN 3600, Malvern Instruments,
Worcestershire, UK) operating at a fixed scattered angle
of 173˚ was used for all the samples of oil in water emul-
sions. The mean droplet diameter (Z-average) of the
samples and polydispersity indices were calculated from
the droplet size distribution. Z-average size (also known
as the “cumulants mean”) is the size to use if a number
is required for quality control purposes. In DLS, this is
the most important and stable number produced by
Z-average technique. The software used to collect and
analyze the data was the Zetasizer®
Software (version
7.03). These parameters were obtained from the auto-
correlation function using the “general purpose mode”
analysis model. Also, measurements were controlled at
25˚C; each measurement was repeated for three times
and the average value was reported.
Refractive index (RI) value of 1.59 was used for
emulsion solution with several concentration of clove
oil. For the sample RI, it is only required to display or
print the result as a volume distribution. It is not
required for calculation of the Z-average size.
2.7. Zeta potential measurements
Zeta potentials of nanoemulsion samples were
measured in a disposable folded capillary cell model
DTS1070 (Malvern Instruments, Worcestershire, UK)
at 25˚C using the Zetasizer®
Nano ZS (model ZEN
3600, Malvern Instruments, Worcestershire, UK) were
controlled through the Zetasizer®
Software (version
7.03). Before any measurements, cells were allowed to
equilibrate at 25˚C for 120 s. All experiments were
performed in triplicates. The average and standard
deviation of the zeta potential were calculated from
three separately independent prepared samples
measurements.
3. Results and discussion
There is no scientific literature to demonstrate
preparation and optimization of clove oil nanoemul-
sion by ultrasonic emulsification using Taguchi
method. Also, the nanoemulsion droplet size of less
than 50 nm has not been reported in the literature. In
this work, the responses of 3 variables known as least
average of droplet size (nm) (Y1); PDI (Y2) and zeta
potential (mV) (Y3) for the desired experimental out-
come were 28.8 nm, 0.38, and −40.1 mV, respectively
(Table 4).
3.1. Signal-to-noise ratio
The mean value of the S/N ratio in decibel
(dB) at different levels of the process parameter
for mean droplet size (nm), PDI, and zeta potential
(mV) are illustrated S/N graphs in Fig. 3(a)–(c),
respectively. Basically, it is defined that smaller S/
N ratio is the better quality characteristic for the
nanoemulsion.
3.2. ANOVA
The purpose of ANOVA is to investigate which
process parameter significantly affected the properties
of clove oil nanoemulsion such as, nanoemulsion
mean diameter under 50 nm with zeta potential below
−30 mV (high stability), and lowest PDI. Table 5 con-
tains the ANOVA for (a) mean droplet size (nm), (b)
PDI and (c) zeta potential (mV). In this table, the rows
marked as “Error” that refer to errors caused by
uncontrollable factors (noise) that are not included in
the experiment and the experimental error. In general,
Fig. 2. Schematic diagram of the experimental set up for preparation of clove oil nanoemulsion.
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8. the value should be less than 50%, otherwise, results
would not be reliable. Here, the calculated error was
about 0.1% for mean droplet size experiments, 16.7%
for PDI, and 0.5% for zeta potential experiments. It
can be seen that these are significantly under the limit.
It means that nearly all important and effective factors
have been considered and that errors in the
experiments are not significant.
Fig. 4 shows the contribution of clove oil concen-
tration which has highly significant effect on
nanoemulsions’ performance indicators; especially in
the case of mean droplet size of nanoemulsions that
had superior effects. On the contrary, the effect of
emulsifier concentration was the lowest among the
other experimental factors. In addition, the effect of
mixed HLB number was considered on zeta potential
Table 4
Responses of various nanoemulsions of clove oil (mean ± SD, replicated 3 times)
Experimental run number
Responses
Y1 Y2 Y3
1 127.8 ± 2.3 0.46 ± 0.03 −30.9 ± 0.60
2 134.6 ± 2.6 0.38 ± 0.06 −13.0 ± 0.44
3 310.3 ± 6.2 0.56 ± 0.02 −10.4 ± 0.21
4 60.5 ± 1.7 0.52 ± 0.02 −29.5 ± 0.67
5 57.7 ± 1.5 0.55 ± 0.02 −16.3 ± 0.57
6 49.1 ± 2.3 0.50 ± 0.01 −29.5 ± 0.95
7 47.0 ± 1.3 0.49 ± 0.01 −32.4 ± 0.15
8 34.0 ± 1.2 0.49 ± 0.05 −40.1 ± 1.04
9 28.8 ± 1.6 0.48 ± 0.03 −17.3 ± 0.35
Notes: Y1 (mean droplet size (nm)); Y2 (PDI); Y3 (zeta potential (mV)).
Fig. 3. S/N ratio graphs for (a) mean droplet size (nm), (b) PDI, and (c) zeta potential (mV).
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9. and PDI. The obtained data showed that the ultrason-
ication time was another effective parameter on PDI
and particle size of nanoemulsion.
ANOVA may be used to estimate the process
performance at optimum conditions. In Taguchi
method, optimum conditions are those that may result
in the smallest S/N ratio. Levels with a low S/N ratio
are those that represent the optimum conditions for a
considered factor. Based on ANOVA results, the pro-
cess parameter for the optimal clove oil nanoemulsion
properties are not the same. The results of optimum
conditions of mean droplet size, PDI, and zeta poten-
tial are listed in Table 6. The S/N ratio at optimum
condition and the expected condition has resulted in
minimum droplet size. The processing conditions for
attaining optimal concentration of clove oil (A) at level
3, concentration of emulsifier amount (B) at level 2;
HLB number (C), and ultrasonication time (D) at level
1, are found to be optimum. At the optimum condi-
tions predicted by Taguchi method, the S/N ratio
improved to about −29.5 dB. Thus, the expected value
of the droplet size at optimum conditions was 30 nm.
Table 6 part “b” shows that the predicted condi-
tions to give minimum PDI are similar to the experi-
mental conditions of run 2 (Table 2). At the optimum
conditions expected by Taguchi method, the S/N ratio
was defined as 0.374 dB. Thus, the obtained PDI based
on the S/N 0.374 is approximately 0.38. The reason for
this improvement is that the levels (experimental
conditions) in optimum conditions are those with the
smallest S/N ratio.
The expected S/N ratios for zeta potential at
optimum condition, such as concentration of clove oil
amount (A) and ultrasonication time (D) at level 3, and
concentration of emulsifier amount (B), and HLB num-
ber (C) at level 1was about −47.9 mV (Table 6 part c).
Table 7 shows the specific optimum conditions for
clove oil nanoemulsion. In fact, our goal is at optimal
conditions to obtain droplet size of 50 nm with mini-
mum PDI and zeta potential (mV).
In comparison of actual experimental data with
predicted values which were projected by Taguchi
method using the information defined in final step of
optimization, the experimental values were quite close
Table 5
ANOVA for (a) mean droplet size (nm), (b) PDI, and (c) zeta potential (mV)
Factors DOF (f) Sum of sqrs. (SS) Variance (V) F-ratio (F) Percent P (%)
(a) Mean droplet size (nm)
Clove oil concentration (wt%) 2 127,329.1 63,670.4 10,914.7 66.2
Emulsifier concentration (wt%) 2 16,547.5 8,279.6 1,419.3 8.6
Mixed HLB number 2 26,093.6 13,052.6 2,237.5 13.5
Ultrasonication time (s) 2 22,261.8 11,136.8 1,909.1 11.6
Error 18 105.0 0.0 0.1
Total 26 192,383.7 100.0%
(b) PDI
Clove oil concentration (wt%) 2 0.016 0.008 16.224 19.612
Emulsifier concentration (wt%) 2 0.008 0.004 8.297 9.400
Mixed HLB number 2 0.024 0.012 24.896 30.784
Ultrasonication time (s) 2 0.019 0.009 19.207 23.455
Error 18 0.008 0.000 16.749
Total 26 0.077 100.00%
(c) Zeta potential (mV)
Clove oil concentration (wt%) 2 633.6 316.8 720.5 24.8
Emulsifier concentration (wt%) 2 654.4 327.2 744.3 25.7
Mixed HLB number 2 1,128.2 564.1 1,283.1 44.2
Ultrasonication time (s) 2 123.9 61.9 140.9 4.8
Error 18 7.9 0.4 0.5
Total 26 2,548.0 100.0%
0
10
20
30
40
50
60
70
Mean Droplet Size (nm) Polydispersity Index Zeta Potential (mV)
Contribution
(%)
Clove oil concentration (wt%)
Emulsifier concentration (wt%)
Mixed HLB number
Ultrasonication time (s)
Error
Fig. 4. Results of ANOVA for test series, contribution of
each factor on the performance indicators.
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10. and comparable to the predicted values (Table 8). The
predicted values for zeta potential, mean droplet size,
and PDI were −47.9 mV, 47.75 nm, and 0.509,
respectively. In addition, the experimental values for
zeta potential, droplet size, and PDI were −40.7 mV,
50 nm and 0.496, respectively. The finalized
formulations at optimal conditions were utilized for
MIC and MBC tests.
3.3. Validation experiment for Taguchi optimal prediction
compare to experimental data
Validation experiments are required, in order to
verify the expected results of clove oil nanoemulsion
obtained at the optimal level for processing factors. If
the observed results in the confirmation experiments
are within the confidence limit (5%), then the pro-
jected results, according to Taguchi method outputs
are acceptable. Validation experiments were per-
formed for optimum levels. The observed values of
mean droplet size (level: A3, B2, C1, and D1), PDI
(level: A1, B2, C2, and D2) and zeta potential (level:
A3, B1, C1, and D3) were 32.2 ± 2.3 nm, 0.38 ± 0.06
and −40.7 ± 2.04 mV, respectively.
The mean values of droplet size, PDI, and zeta
potential at optimum condition were projected by
Taguchi L9 OA design, as 30 nm, 0.374 and −47.9 mV,
respectively.
The data shows the determined range of desirabil-
ity of data which is about 85% confidence interval. It
can be seen that the clove oil nanoemulsion is greatly
improved at the defined levels. The zeta potential of
optimum clove nanoemulsion has suitable physical
stability of formulation.
As particles with potential higher than +30 mV
and lower than −30 mV are considered stable, the high
stability of nanoemulsions at high zeta potential value
is attributed to presence of high surface charge. It
reduces the risk of coagulation due to electrostatic
repulsion between particles bearing same electric
charges, and makes the system stable for longer time
and allows easy re-dispersion.
3.4. Bacteriostatic and bactericidal activity of optimum
formula of clove oil nanoemulsion
Clove oil nanoemulsions were slightly more potent
against E. coli compared to B. cereus. The MIC and
MBC concentrations on E. coli and B. cereus were 16,
16, 32, and 64 μg/ml, respectively. For E. coli, the
MBC and MIC values were identical, indicating that
the effect of clove oil is mainly bactericidal and not
bacteriostatic. This is due to the presence of eugenol
as organic phenolic compound found in clove oil,
which can denature proteins. Eugenol can react with
phospholipids from cell membrane, and also it
Table 6
Optimum conditions for mean droplet size, PDI and zeta potential
Factors
(a) Mean droplet size
(nm) (b) PDI (c) Zeta potential (mV)
Level Description Level Description Level Description
Clove oil concentration (wt%) 3 15 1 2.5 3 15
Emulsifier concentration (wt%) 2 5 2 5.0 1 2.5
Mixed HLB number 1 9 2 12.0 1 9
Ultrasonication time (s) 1 150 2 300 3 150
Expected result at optimum
condition
30 0.374 −47.88
Table 7
Desirability specifications for clove oil nanoemulsion
Name Goal Lower limit Upper limit
Clove oil concentration (wt%) within the range 2.5 15
Emulsifier concentration (wt%) within the range 2.5 7.5
Mixed HLB number within the range 9.0 15
Ultrasonication time (s) within the range 150 450
Mean droplet size (nm) is targeted 50 28.8 ± 1.6 310.3 ± 6.2
PDI minimize 0.38 ± 0.06 0.56 ± 0.02
Zeta Potential (mV) minimize −40.1 ± 1.04 −10.4 ± 0.21
M.H. Shahavi et al. / Desalination and Water Treatment 9
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11. interacts with cell membrane permeability in a great
number of bacteria and yeasts [15,33–35]. The
antibacterial activity of clove oil in comparison to
clove oil nanoemulsion was insignificant due
instability of raw clove oil. The MICs test for E. coli
and B. cereus are shown in Fig. 5.
4. Conclusions
In this research, the processing factors for the
preparation of clove nanoemulsion were optimized.
The nanoemulsion is a biodegradable and green pesti-
cide according to intended application. Based on
Taguchi design method, the formulation of nanoemul-
sions consists of mixing three components, clove oil,
water, and two different mixed surfactants via ultra-
sonication method. The error values according to
Taguchi method for these experiments were insignifi-
cant. Hence, it was concluded that nearly all impor-
tant and effective factors were considered and that
errors in the experiments were also insignificant.
Based on targeted nanoemulsion with high degree
of stability with zeta potential below −30 mV and
lowest PDI obtained at optimum conditions a mean
droplet size of 50 nm was achieved. The high degree
of stability of nanoemulsion is secured by the value of
zeta potential lower than −30 mV and low PDI value
(sized within 50 nm).
The experiments for validation observed that mean
droplet size, PDI, and zeta potential (32.2 ± 2.3 nm,
0.38 ± 0.06 and −40.7 ± 2.04 mV, respectively), were
within the expected range of the value’s for confidence
limit, (30 nm, 0.374 and −47.9 mV, respectively).
To achieve all the properties at the same processing
condition one has to go for a desired compromise by
trading-off one of the nanopesticide properties. The
optimum formula of clove oil nanoemulsion showed
high antibacterial activity against all the tested bacteria.
The present study suggests that the clove oil nanoemul-
sion is a potential source of natural antibacterial agents
and to be used as food preservatives.
Acknowledgement
The authors would like to acknowledge the biofilm
group of Interdisciplinary Nanoscience Center
(iNANO), Aarhus University, Denmark for their
support and contribution to present work.
Table 8
Experimental and predicted optimal conditions for clove oil nanoemulsion
Factors
Mean droplet size (nm) PDI Zeta potential (mV)
A B C D
15 2.5 9 450 Predicted 47.75 0.509 −47.9
Experimental 50.43 ± 0.91 0.496 ± 0.25 −40.7 ± 2.04
0
20
40
60
80
100
120
Growth
(normalized
%)
Clove oil nanoemulsion concentration (µg/ml )
E. coli B. Cereus
Fig. 5. Normalized growth vs. clove oil nanoemulsion concentration for MIC test.
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