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کاربرد نوع شرط:
- جایگاه : پژوهشی
- مجله: Progress in Biological Sciences
- نوع مقاله: Journal Article
- کلمات کلیدی: Taguchi Method,Decolorization,Azo dye,halophilic bacteria,media optimization
- چکیده:
- چکیده انگلیسی: Halophilic and halotolerant microorganisms are good candidates for decolorization of azo dyes
which are routinely used in the dyeing process in textile industries. In this paper, the
optimization of biological decolorization of synthetic dye solutions containing Remazol Black B
by the previously isolated halophilic bacterium Halomonas sp. D2 is investigated. In a primary
investigation using a one-factor–at-a-time method, temperature, initial pH of the solution, and
concentrations of glucose, yeast extract, and sodium chloride were chosen for optimizing dye
removal using the Taguchi method. Based on the statistical analysis of the results, the most
significant parameter by far was the yeast extract concentration which accounted for 72.67% of
the total effect, followed by pH (11.84%) and the NaCl concentration (8.90%). The optimized
conditions for dye removal were predicted to be a temperature of 35°C, an initial pH of 10,
glucose concentration of 1% (w/v), yeast extract concentration of 1% (w/v), and sodium
chloride of 10% (w/v). Under these conditions, 95% decolorization was achieved in confirming
experiments.- انتشار مقاله: 09-09-1392
- نویسندگان: Sedigheh Asad,Seyed Mohammad Mehdi Dastgheib,Mohammad Ali Amoozegar
- مشاهده
- جایگاه : پژوهشی
- مجله: Progress in Biological Sciences
- نوع مقاله: Journal Article
- کلمات کلیدی: Iran,identification,Characterization,Taxonomy,Microbial diversity,polyphasic approach
- چکیده:
- چکیده انگلیسی: Microorganisms constitute more than half of the Earth's biomass and in addition to quantity,
they represent great diversity. In January 2013, the number of officially registered names for
prokaryotic microorganisms at the genus and species levels were, respectively, approximately
2100 and 12000. Current authorized methods for classification and identification of new
microbial taxa are polyphasic approaches which make use of a codified set of characteristics
for classification of microorganisms. Here, we present a brief overview of criteria by which
prokaryotes are classified and subsequently summarize some recent findings on the microbial
flora of Iran. Among all microbial taxa identified to date, six taxa at the genus level and 24
taxa at the species level were first discovered in and reported from Iran. This attests to the
existence of a rich microbial diversity in Iran. Among the species, four belong to the Archaea
and the others belong to the Bacteria domain. The bacterial taxa consist of six Gram- negative
species within Proteobacteria and Bacteroidetes phylems and 20 Gram-positive taxa that
are among the Actinobacteria, Firmicutes and related organisms. It is incumbent that further
focus be placed on the rich ecological diversity of Iran, and it is expected that this will result
in identification of new endemic microorganisms.- انتشار مقاله: 19-08-1392
- نویسندگان: Mohammad Ali Amoozegar,Maliheh Mehrshad
- مشاهده
- جایگاه : پژوهشی
- مجله: Progress in Biological Sciences
- نوع مقاله: Journal Article
- کلمات کلیدی:
- چکیده:
- چکیده انگلیسی: Production of extracellular amylase was demonstrated under conditions of high salinity in aerobically cultivated culture of a newly isolated moderately halophilic Gram-positive coccus, designated strain F in basal medium containing peptone from meat, yeast extract, NaCl (7% w/v) and starch. Biochemical and physiological characterization along with 16S rRNA sequence analysis placed F in the genus Nesterenkonia. The enzyme production was synchronized bacterial growth and reached a maximum level during the early-stationary phase in the basal medium. Maximum yield production was observed when the soluble starch, yeast extract and NaCl (1%, 0.75% and 10% w/v, respectively) were used in the fermentation medium with pH 8.0, inoculated with 7% (v/v) pre-culture medium and incubated in 30°C for 72 h with aeration of 250 rpm (299.25 U/ml).
The potential of different carbohydrates in amylase production was in the order: starch> maltose>dextrin>fructose>lactose=glucose>sodium acetate>sodium citrate. The production yield in the presence of different salts was as follows: NaCl> KCl> NaNO3> Na2SO4. Maximum activity for enzyme was assayed in 3.0 M NaCl, pH: 5-7, and 40°C. α-amylase hydrolyzed starch, dextrin and glycogen to form maltose, maltotriose and maltotetraose as major products, and has no effect on amylose and pullulan as substrates. These results suggest that the amylase secreted by Nesterenkonia sp. strain F is industrially important from the perspective of its tolerance to a broad temperature range and its high tolerance to a wide range of salt concentrations (0–3 M NaCl).- انتشار مقاله: 16-07-1391
- نویسندگان: Mohammad Ali Amoozegar,Bardia Samareh-Abolhasani,Mohammad Shafiei,Maryam Didari,Javad Hamedi
- مشاهده
- جایگاه : پژوهشی
- مجله: Progress in Biological Sciences
- نوع مقاله: Journal Article
- کلمات کلیدی: heavy metals,Bioremediation,Atomic absorption,Moderate halophiles
- چکیده:
- چکیده انگلیسی: Toxic heavy metals, such as lead (Pb) and cadmium (Cd) are widely used in industry and their accumulation in the living tissues may cause serious health problems and ecological hazards. Twenty four moderately halophilic bacteria isolated from saline environments of Iran were used to study their ability to bioremediation of lead and cadmium. Amongst them, a Gram-negative rod shaped bacterium, designated as strain D showed remarkable ability for removal of Pb and Cd and could grow in media supplemented with 5 mM of these toxic heavy metals. Phenotypic characterization and phylogenetic analysis based on 16S rRNA gene sequence comparisons indicate this strain belongs to the genus Halomonas. Atomic absorption (AA) spectroscopy was used to estimate the removal rate of lead and cadmium by bacterial biomass, autoclaved biomass and exopolysaccharide (EPS) matrix under different conditions. The strain D could uptake more than 90% and 50% of lead and cadmium, respectively. Biomass showed the best lead removal at pH 3.0- 6.0, 35 °C and 5% NaCl (w/v), while the EPS showed maximum removal at pH 5.0, 35 °C and 10% NaCl (w/v). For cadmium removal by biomass, the best results were obtained at pH 3.0, 25 °C and 1% NaCl (w/v) while the EPS showed the optimal cadmium removal at pH 5.0, 45 °C and 1% NaCl (w/v). The results suggest that halophilic bacteria such as Halomonas sp. could be used for remediation of Pb and Cd in contaminated saline soils and wastes discharge sites
- انتشار مقاله: 11-10-1348
- نویسندگان: Mohammad Ali Amoozegar,Nooshinsadat Ghazanfari,Maryam Didari
- مشاهده
- جایگاه : پژوهشی
- مجله: Progress in Biological Sciences
- نوع مقاله: Journal Article
- کلمات کلیدی: Taguchi Method,Decolorization,Azo dye,halophilic bacteria,media optimization
- چکیده:
- چکیده انگلیسی: Halophilic and halotolerant microorganisms are good candidates for decolorization of azo dyes
which are routinely used in the dyeing process in textile industries. In this paper, the
optimization of biological decolorization of synthetic dye solutions containing Remazol Black B
by the previously isolated halophilic bacterium Halomonas sp. D2 is investigated. In a primary
investigation using a one-factor–at-a-time method, temperature, initial pH of the solution, and
concentrations of glucose, yeast extract, and sodium chloride were chosen for optimizing dye
removal using the Taguchi method. Based on the statistical analysis of the results, the most
significant parameter by far was the yeast extract concentration which accounted for 72.67% of
the total effect, followed by pH (11.84%) and the NaCl concentration (8.90%). The optimized
conditions for dye removal were predicted to be a temperature of 35°C, an initial pH of 10,
glucose concentration of 1% (w/v), yeast extract concentration of 1% (w/v), and sodium
chloride of 10% (w/v). Under these conditions, 95% decolorization was achieved in confirming
experiments.- انتشار مقاله: 09-09-1392
- نویسندگان: Sedigheh Asad,Seyed Mohammad Mehdi Dastgheib,Mohammad Ali Amoozegar
- مشاهده
- جایگاه : پژوهشی
- مجله: Progress in Biological Sciences
- نوع مقاله: Journal Article
- کلمات کلیدی: Iran,identification,Characterization,Taxonomy,Microbial diversity,polyphasic approach
- چکیده:
- چکیده انگلیسی: Microorganisms constitute more than half of the Earth's biomass and in addition to quantity,
they represent great diversity. In January 2013, the number of officially registered names for
prokaryotic microorganisms at the genus and species levels were, respectively, approximately
2100 and 12000. Current authorized methods for classification and identification of new
microbial taxa are polyphasic approaches which make use of a codified set of characteristics
for classification of microorganisms. Here, we present a brief overview of criteria by which
prokaryotes are classified and subsequently summarize some recent findings on the microbial
flora of Iran. Among all microbial taxa identified to date, six taxa at the genus level and 24
taxa at the species level were first discovered in and reported from Iran. This attests to the
existence of a rich microbial diversity in Iran. Among the species, four belong to the Archaea
and the others belong to the Bacteria domain. The bacterial taxa consist of six Gram- negative
species within Proteobacteria and Bacteroidetes phylems and 20 Gram-positive taxa that
are among the Actinobacteria, Firmicutes and related organisms. It is incumbent that further
focus be placed on the rich ecological diversity of Iran, and it is expected that this will result
in identification of new endemic microorganisms.- انتشار مقاله: 19-08-1392
- نویسندگان: Mohammad Ali Amoozegar,Maliheh Mehrshad
- مشاهده
- جایگاه : پژوهشی
- مجله: Progress in Biological Sciences
- نوع مقاله: Journal Article
- کلمات کلیدی:
- چکیده:
- چکیده انگلیسی: Production of extracellular amylase was demonstrated under conditions of high salinity in aerobically cultivated culture of a newly isolated moderately halophilic Gram-positive coccus, designated strain F in basal medium containing peptone from meat, yeast extract, NaCl (7% w/v) and starch. Biochemical and physiological characterization along with 16S rRNA sequence analysis placed F in the genus Nesterenkonia. The enzyme production was synchronized bacterial growth and reached a maximum level during the early-stationary phase in the basal medium. Maximum yield production was observed when the soluble starch, yeast extract and NaCl (1%, 0.75% and 10% w/v, respectively) were used in the fermentation medium with pH 8.0, inoculated with 7% (v/v) pre-culture medium and incubated in 30°C for 72 h with aeration of 250 rpm (299.25 U/ml).
The potential of different carbohydrates in amylase production was in the order: starch> maltose>dextrin>fructose>lactose=glucose>sodium acetate>sodium citrate. The production yield in the presence of different salts was as follows: NaCl> KCl> NaNO3> Na2SO4. Maximum activity for enzyme was assayed in 3.0 M NaCl, pH: 5-7, and 40°C. α-amylase hydrolyzed starch, dextrin and glycogen to form maltose, maltotriose and maltotetraose as major products, and has no effect on amylose and pullulan as substrates. These results suggest that the amylase secreted by Nesterenkonia sp. strain F is industrially important from the perspective of its tolerance to a broad temperature range and its high tolerance to a wide range of salt concentrations (0–3 M NaCl).- انتشار مقاله: 16-07-1391
- نویسندگان: Mohammad Ali Amoozegar,Bardia Samareh-Abolhasani,Mohammad Shafiei,Maryam Didari,Javad Hamedi
- مشاهده
- جایگاه : پژوهشی
- مجله: Progress in Biological Sciences
- نوع مقاله: Journal Article
- کلمات کلیدی: heavy metals,Bioremediation,Atomic absorption,Moderate halophiles
- چکیده:
- چکیده انگلیسی: Toxic heavy metals, such as lead (Pb) and cadmium (Cd) are widely used in industry and their accumulation in the living tissues may cause serious health problems and ecological hazards. Twenty four moderately halophilic bacteria isolated from saline environments of Iran were used to study their ability to bioremediation of lead and cadmium. Amongst them, a Gram-negative rod shaped bacterium, designated as strain D showed remarkable ability for removal of Pb and Cd and could grow in media supplemented with 5 mM of these toxic heavy metals. Phenotypic characterization and phylogenetic analysis based on 16S rRNA gene sequence comparisons indicate this strain belongs to the genus Halomonas. Atomic absorption (AA) spectroscopy was used to estimate the removal rate of lead and cadmium by bacterial biomass, autoclaved biomass and exopolysaccharide (EPS) matrix under different conditions. The strain D could uptake more than 90% and 50% of lead and cadmium, respectively. Biomass showed the best lead removal at pH 3.0- 6.0, 35 °C and 5% NaCl (w/v), while the EPS showed maximum removal at pH 5.0, 35 °C and 10% NaCl (w/v). For cadmium removal by biomass, the best results were obtained at pH 3.0, 25 °C and 1% NaCl (w/v) while the EPS showed the optimal cadmium removal at pH 5.0, 45 °C and 1% NaCl (w/v). The results suggest that halophilic bacteria such as Halomonas sp. could be used for remediation of Pb and Cd in contaminated saline soils and wastes discharge sites
- انتشار مقاله: 11-10-1348
- نویسندگان: Mohammad Ali Amoozegar,Nooshinsadat Ghazanfari,Maryam Didari
- مشاهده
- جایگاه : پژوهشی
- مجله: Journal of Advances in Environmental Health Research
- نوع مقاله: Journal Article
- کلمات کلیدی: Water,Arsenic species,ICP-AES,Total arsenic,Babagorgor fountain,SDDC
- چکیده:
- چکیده انگلیسی: Since Babagorgorfountain in the Ghorveh city of Kurdistan province is located in the arsenic belt of Iran, to raise awareness about the quality of drinking water from this fountain the concentration of arsenic and other heavy metals as well as other physicochemical parameters were investigated to protect the public health. In this study, water samples were collected from Babagorgorfountain. Arsenic in the water was measured by field and laboratory methods. Its concentration was estimated to be more than 500 ppb in a field method and 596 ppb in a SDDC method with absorbance measurements at 520 nm. The SDDC method can measure arsenic species separately and the concentration of arsenite and arsenate were found to be 239 and 357 ppb, respectively. Other physiochemicalparameters and heavy metals in the fountain water were evaluated according to standard methods. According to the World Health Organization guidelines the maximum safe level of arsenic in drinking water is 10 ppb. The concentration of arsenic in this fountain’s water is estimated at 60 times the limit and therefore its use is very dangerous for public health.
- انتشار مقاله: 13-06-1396
- نویسندگان: Mohammad Ahmadi Jebelli,Afshin Maleki,Mohammad Ali Amoozegar,Enayatollah Kalantar,Behzad Shahmoradi
- مشاهده
- جایگاه : پژوهشی
- مجله: Journal of Advances in Environmental Health Research
- نوع مقاله: Journal Article
- کلمات کلیدی: Water,Arsenic species,ICP-AES,Total arsenic,Babagorgor fountain,SDDC
- چکیده:
- چکیده انگلیسی: Since Babagorgorfountain in the Ghorveh city of Kurdistan province is located in the arsenic belt of Iran, to raise awareness about the quality of drinking water from this fountain the concentration of arsenic and other heavy metals as well as other physicochemical parameters were investigated to protect the public health. In this study, water samples were collected from Babagorgorfountain. Arsenic in the water was measured by field and laboratory methods. Its concentration was estimated to be more than 500 ppb in a field method and 596 ppb in a SDDC method with absorbance measurements at 520 nm. The SDDC method can measure arsenic species separately and the concentration of arsenite and arsenate were found to be 239 and 357 ppb, respectively. Other physiochemicalparameters and heavy metals in the fountain water were evaluated according to standard methods. According to the World Health Organization guidelines the maximum safe level of arsenic in drinking water is 10 ppb. The concentration of arsenic in this fountain’s water is estimated at 60 times the limit and therefore its use is very dangerous for public health.
- انتشار مقاله: 13-06-1396
- نویسندگان: Mohammad Ahmadi Jebelli,Afshin Maleki,Mohammad Ali Amoozegar,Enayatollah Kalantar,Behzad Shahmoradi
- مشاهده