一株酸性淀粉酶产生菌的筛选与发酵条件的优化

一株酸性淀粉酶产生菌的筛选与发酵条件的优化(11800字)
摘 要 ：从浏阳河畔的土壤中筛选到1株酸性淀粉酶的产生菌株OYC07,经形态学分析为芽孢杆菌.液态发酵条件研究表明,产酶适宜培养基为麸皮以6%在32 ℃、180 rpm、初始pH 4.5的条件下培养84 h,酶活力达到1220 U/mL.用聚丙烯酰胺活性凝胶电泳测出该酶的分子量大小是30 kDa，酶学特性研究表明,该酸性淀粉酶最适反应温度为50 ℃,最适反应pH值为3.5,在70 ℃高温处理30 min酶活力保持95%。
关键词：耐酸淀粉酶；筛选；聚丙烯酰胺活性凝胶电泳；

Screening of strain producing an acid amylase and optimization of fermentation conditions
Abstract：An acid amylase producing strain OYC07, was screened from sail near Liu yang River. Morphology analysis indicated OYC07 was Bacillus sp with spore 1.0 um .Fermentation conditions studies showed the acid amylase activity reached 1220 u/mL when cultured with wheat bran 6%, at 32 ℃, 180 r/min, initial pH4.5 for 84 h. Enzymology characteristics analysis showed that the amylase of strain OYC07 had a molecular weight31 kDa investigated by method of SDS-PAGE,with optimum temperature is 50 ℃, optimum pH3.5 and maintained 95% amylase activity after keeping at 70 ℃ for 30 min .
Key words：acid amylase；screening； polyacrylamide gel electrophoresis activity；