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کاربرد نوع شرط:
- 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:
- 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