Biotechnology & nanotechnology
Naimeh Khazali; Maryam Sadrnia; Reza Hajihosseini
Abstract
Background: Microbial lipases are an important group of enzymes with biotechnology value. In the present research, an attempt was made to isolate and identify lipase-producing microbial strains from industrial wastewater samples.Materials and Methods: After taking samples from sewage and sewage from ...
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Background: Microbial lipases are an important group of enzymes with biotechnology value. In the present research, an attempt was made to isolate and identify lipase-producing microbial strains from industrial wastewater samples.Materials and Methods: After taking samples from sewage and sewage from different places,16 colonies were isolated from these samples. The isolates were cultured in a specific culture medium containing Tween80 to check the ability to produce lipase enzyme. Enzyme activity was determined using the light absorption curve. In order to identify the isolates molecularly, ribotyping was performed. For this purpose, the DNA of the isolates was extracted and PCR was performed with the help of 16SrRNA gene primers. The PCR product was sequenced and the strains were identified using sequence blast in the NCBI database.Results: Out of a total of 16 isolates, ten strains (62.5%) were able to produce lipase enzyme as a result of creating a transparent halo in the culture medium of the lipid test. Among these, two isolates with the same halo formation rate and source of isolation, which had the highest growth and activity after 144 hours were selected from the culture. Enzyme activity values for bacteria isolated from slaughterhouse effluent and garage effluent ranged from 2.99 to 22.65 and 3.73to 39.2 units/ml, respectively.Conclusion: Due to their very high lipase activity compared to the strains introduced in other researches, Aeromonas veroni and Copriavidus metallidurans bacteria are suggested as very suitable and efficient strains for the biological treatment of wastewater.
Health and environment
Ramezan Sadeghi; Mehraban Sadeghi; Rahman Abdizadeh; Morteza Sedehi; Morteza Hashemzadeh Chaleshtori; Shahrbanou Parchami Barjui; Mohammad Rasoul Asadi Amirabadi
Volume 28, Issue 6 , January and February 2022, , Pages 982-994
Abstract
Backgrounds: Similar to some organic materials the heavy metals are not easily removed from the environment because of the toxic nature and form a class of stable and non-biodegradable pollutants. These elements enter the nature and the food chain as a result of natural activities such as eruptions of ...
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Backgrounds: Similar to some organic materials the heavy metals are not easily removed from the environment because of the toxic nature and form a class of stable and non-biodegradable pollutants. These elements enter the nature and the food chain as a result of natural activities such as eruptions of volcanoes and human activities such as mining, producing industrial and urban wastewaters and applying pesticides.Materials and Methods: In this study, chrome (VI) -resistant bacteria were isolated from the industrial wastewater taken from Isfahan Mobarakeh Steel Complex. The isolated strains were identified and their resistance to chromium was determined and the strain with the highest resistance to chromium was used for its bioremediation.Data were analyzed using descriptive statistics and one way ANOVA.Results: The results of this study led to the identification of five chrome resistant strains that the Micrococcus luteus SEHD031RS bacterium was detected as the best chrome resistant strain due to the minimum inhibitory concentration of 140 mgL-1 and minimum bactericidal concentration of 152 mgL-1. In this study, the highest chromium removal rate of 82.5% was obtained at pH 4, concentration of 30 mgL-1 and 96 hours.Conclusion: The results of this study indicate that the Micrococcus luteus SEHD031RS strain can be used as an effective microorganism in removing chromium from industrial wastewater or environmental bioremediation.
Health and environment
tahereh zarei mahmoudabadi; Mohammad Hassan Ehrampoush; parvaneh talebi
Volume 28, Issue 3 , May and June 2021, , Pages 397-405
Abstract
Introduction: The production of high wastewater is one of the problems of recycling paper industry, it is essential to provide appropriate economic and environmental solutions for proper management and treatment. So in this research, the purpose was of optimization the treatment of wastewater products ...
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Introduction: The production of high wastewater is one of the problems of recycling paper industry, it is essential to provide appropriate economic and environmental solutions for proper management and treatment. So in this research, the purpose was of optimization the treatment of wastewater products from the paper recycling industry with using magnesium chloride in combination with cationic and anionic polyacrylamides.
Materials and Methods: This was an applied researchwhich was done on a laboratory scale. The different pH (4-12) values at a fixed concentration of magnesium chloride to determine the optimum pH was investigated. Then optimization of concentration for magnesium chloride (200-700 mg/L) and polyacrylamides (0.5-3 mg/L) was performed. At each stage of optimization, the parameters of TSS and COD were measured. Pearson correlation coefficient was used for analysis of data and significance level was 0.05.
Results: According to the results, pH=10 as optimal pH and concentrations of 500 and 1.5 mg / L were selected as optimal concentrations for magnesium chloride and cationic polyacrylamide, respectively. Under optimal conditions, the efficiency of removing TSS and COD was 96% and 83.07%, respectively.
Conclusion: The results showed that magnesium chloride combined with cationic polyacrylamide, can be used as an appropriate option for wastewater treatment of paper recycling industries.
Fatemeh Adami ghamsari; Farzaneh Hosseini; Anita Khanaferi
Volume 22, Issue 4 , September and October 2015, , Pages 685-685
Abstract
Background & Objectives: Today, entrance of wastewaters, especially detergent and cleaner agent’s production industries wastewaters, to surface and underground waters is one of environmental pollution concerns. These wastewaters are containing detergents and surfactants, such as polysorbates ...
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Background & Objectives: Today, entrance of wastewaters, especially detergent and cleaner agent’s production industries wastewaters, to surface and underground waters is one of environmental pollution concerns. These wastewaters are containing detergents and surfactants, such as polysorbates and, because of exposure of human and other organisms, their degradation is of great important. This research analyses degradation of a non-ionic detergent in polysorbate group called Tween 80 (polysorbate 80) and studies effect of pH and temperature on degradation rate of this detergent, using lipolytic bacteria (isolated from Tehran oil refinery wastewater and activated sludge). Materials & Methods: For primary isolating of lipolytic bacteria, the TSA medium containing Tween 80 and olive oil has been, separatively, used. Then specific culture Tween agar and Tributyrin agar have been used to study for lipase enzyme bacteria production. Also for confirmation degradation, instrumental methods, spectrophotometer and FTIR were used. Results: The results shows that the isolated bacteria are able to depredate polysorbate 80 by lipase enzyme production. Bacillus cereus was known as the best degradator after the identification of the molecular basis of sequencing 16S rRNA. Bacillus cereus ATCC 14579 (T), Pseudomonas aeruginosa and other Bacillus sp was known. Conclusion: The results showed that pH and temperature affects on the degradation of tween, and the Pseudomonas aeruginosa at acidic range of pH, two gram positive bacillus at alkali range of pH and three bacteria at 37 ˚C have the best degradation.