产脂肪酶菌株C7828-5的筛选、鉴定以及产酶条件的优化

以花生油为唯一碳源,从海口市各地被油脂污染土样中分离筛选出1株中温碱性脂肪酶菌株C7828-5。形态学、生理生化特征和分子生物学鉴定结果表明,该菌株为铜绿假单胞菌(Pseudomonas aeruginosa)。该菌所产脂肪酶的最适温度为37℃,最适pH为8.0。优化了菌株的产酶条件,最适产酶培养基(g/L)为:蔗糖5、牛肉膏20、(NH_4)_2SO_41、MgSO_4·7H_2O 0.5、CaCl_20.5,聚乙烯醇花生油乳化液120 mL,发酵72 h,获得高达8.08 U/mL的脂肪酶表达量。

Screening and classification for lipase-producing strain C7828-5 and optimization of its fermentation conditions

A bacteria strain C7828-5 producing warm-adapted alkaline lipase was isolated from lipid-contaminated soil samples in Haikou on a selective medium using peanut oil as the only carbon source. The strain was identified as Pseudomonas aeruginosa based on it morphological, physiological, biochemical and molecular characteristics. The optimal temperature and pH for the lipase were 37 ℃ and pH 8.0, respectively. The optimal medium for lipase production were determined as follows ： sugar 5 g/L, bear extract 20 g/L, （NH4）2SO4 1 g/L, MgSO4·7H2O0.5 g/L, CaCl2 0.5 g/L, emulsified peanut oil 120 mL[L. The alkaline lipase activity reached maximal level of 8.08 U/mL.