摘要: |
从土壤中筛选得到一株产壳聚糖酶菌株P003,对其进行了发酵条件优化。结果表明其最适发酵培养条件为:(NH4)2SO4 2.0%,粉末壳聚糖1.0%,葡萄糖0.1%,K2HPO40.07%,KH2PO40.03%,NaCl 0.5%,MgSO4·7H2O 0.05%,酵母提取物0.3%,调pH至5.0;2.0%接种量,500 mL三角瓶装液量为150 mL,32 ℃下150 r/min摇床培养96 h,在此条件下菌株发酵液的壳聚糖酶活力达108 U/mL。采用硫酸铵分级盐析、离子交换层析和凝胶过滤层析等方法,从菌株的发酵液中分离出了分子质量为30.5 ku的壳聚糖酶。 |
关键词: 壳聚糖酶 发酵条件 分离纯化 |
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基金项目:国家“十五”科技攻关项目(2001BA708B04-07) |
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Study on optimal fermentation conditions of a chitosanase-producing bacterium and purification of the chitosanase |
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Abstract: |
A strain with chitosanase activity was isolated from soil samples. The optimal compositions of the medium for P003 strain producing chitosanase were as follows(W/V): powder chitosan 1.0%, glucose 0.1%, (NH4)2SO4 2.0%,yeast extract 0.3%, K2HPO40.07%,KH2PO40.03%,NaCl 0.5%,MgSO4 ·7H2O 0.05%,the initial pH5.0. The optimal cultivation conditions for P003 producing chitosanase were 500 mL flask containing 150 mL medium, 2.0%(V/V)amount of inoculation , 32℃ incubating temperature and shaking cultivation at 150 r/min for 96 h. The chitosanase activity of the fermented broth is 108 U/mL when P003 was incubated under aforementioned conditions. The chitosanase of the fermented broth was extracted by ammonium sulfate precipitation, and purified by ion-exchange chromatography and gel filtration, and the molecular weight of the chitosanase was estimated to be 30.5 ku. |
Key words: chitosanase fermentation conditions purification |