将在日本收集的α-淀粉酶有关菌种,作了菌种酶活性的比较,发现淀粉液化芽孢杆菌Bacillus amyloliquefaciens KA 63培养在10%可溶性淀粉,2%蛋白胨,1%牛肉膏,0.5%酵母粉,0.5%NaCl,0.5%K_2HPO_4中可获较高的α-淀粉酶酶活,2升发酵罐培养28...将在日本收集的α-淀粉酶有关菌种,作了菌种酶活性的比较,发现淀粉液化芽孢杆菌Bacillus amyloliquefaciens KA 63培养在10%可溶性淀粉,2%蛋白胨,1%牛肉膏,0.5%酵母粉,0.5%NaCl,0.5%K_2HPO_4中可获较高的α-淀粉酶酶活,2升发酵罐培养28-30小时,α-淀粉酶酶活可达400单位/亳升,该菌种具有一定的生产价值,将为我国增添一个液化型α-淀粉酶的新品种。展开更多
A total of 126 bacterial strains were isolated from soil samples. Among them, 11 isolates were found positive for amylase production. Strain YL produced the largest zone of clearance on plate assay. The isolate YL was...A total of 126 bacterial strains were isolated from soil samples. Among them, 11 isolates were found positive for amylase production. Strain YL produced the largest zone of clearance on plate assay. The isolate YL was identified as Bacillus sp. based on morphological and physiochemical characterization. According to 16S rRNA gene sequencing data, the closest phylogenetic neighbor of strain YL was Bacillus amyloliquefaciens （99.54%）. After that, an optimization of culture conditions was carried out for the improvement of a-amylase production. Response surface methodology （RSM） was applied to evaluate the effect of medium components including wheat bran, cottonseed extract, yeast extract, starch, NaC1 and CaCl2. Three variables （wheat bran, cottonseed extract, and starch）, which were identified to significantly affect amylase production by Plackett-Burman design were further optimized using response surface methodology of Box-Behnken design （BBD）. The optimal concentrations estimated for each variable related to the maximum of amylase activity （86 kU/mL） were 10.80 g/L wheat bran, 9.90 g/L cottonseed extract, 0.5 g/L starch, 2.0 g/L yeast extract, 5.00 g/L NaCl and 2.00 g/L CaC12. The fermentation using optimized culture medium allowed a significant increase in amylase production （by 3-fold）. The improvement in the a-amylase production after optimization process can be considered adequate for large-scale applications.展开更多
文摘将在日本收集的α-淀粉酶有关菌种,作了菌种酶活性的比较,发现淀粉液化芽孢杆菌Bacillus amyloliquefaciens KA 63培养在10%可溶性淀粉,2%蛋白胨,1%牛肉膏,0.5%酵母粉,0.5%NaCl,0.5%K_2HPO_4中可获较高的α-淀粉酶酶活,2升发酵罐培养28-30小时,α-淀粉酶酶活可达400单位/亳升,该菌种具有一定的生产价值,将为我国增添一个液化型α-淀粉酶的新品种。
基金Project(31000350) supported by the National Natural Science Foundation of ChinaProject(2010CB630902) supported by the National Basic Research Program of China
文摘A total of 126 bacterial strains were isolated from soil samples. Among them, 11 isolates were found positive for amylase production. Strain YL produced the largest zone of clearance on plate assay. The isolate YL was identified as Bacillus sp. based on morphological and physiochemical characterization. According to 16S rRNA gene sequencing data, the closest phylogenetic neighbor of strain YL was Bacillus amyloliquefaciens （99.54%）. After that, an optimization of culture conditions was carried out for the improvement of a-amylase production. Response surface methodology （RSM） was applied to evaluate the effect of medium components including wheat bran, cottonseed extract, yeast extract, starch, NaC1 and CaCl2. Three variables （wheat bran, cottonseed extract, and starch）, which were identified to significantly affect amylase production by Plackett-Burman design were further optimized using response surface methodology of Box-Behnken design （BBD）. The optimal concentrations estimated for each variable related to the maximum of amylase activity （86 kU/mL） were 10.80 g/L wheat bran, 9.90 g/L cottonseed extract, 0.5 g/L starch, 2.0 g/L yeast extract, 5.00 g/L NaCl and 2.00 g/L CaC12. The fermentation using optimized culture medium allowed a significant increase in amylase production （by 3-fold）. The improvement in the a-amylase production after optimization process can be considered adequate for large-scale applications.
