脂肪酶产生菌的筛选、鉴定及其产酶条件优化

Screening,Identification of Lipase Production Bacteria and Optimization of the Lipase Production

目的:寻找合适的产酶菌。方法:从富油土壤中分离到一株脂肪酶产生菌,并通过16S rRNA部分序列分析和系统发育分析将其鉴定为假单胞菌属,定名为:Pseudomonas sp.26-2。本研究进一步通过正交试验设计对该菌株的产脂肪酶条件进行了优化。结果:在摇瓶培养条件下,其最适产酶条件为:淀粉1.5%,酵母提取物3%,硫酸镁0.05%,K2HPO40.2%,橄榄油0.2%;反应起始pH值为7.0,发酵温度为30℃。在此条件下,发酵脂肪酶活力可达15.5U/ml。结论:所获得的假单胞菌26-2具有一定的脂肪酶生产能力,并为该菌株的菌种改良以及脂肪酶的高效基因工程菌的构建奠定了基础。

Objective：Lipase is an important industrial biocatalyzer and broadly used in a variety of technical application.Appropriate lipase-producing strain is the key for R＆D.Method： A lipase production stain was isolated from oil-strained soil samples,and was identified and denominated as Pseudomonas sp.26 after patial 16S rRNA sequencing and phylogenetic analysis with the homogenous strains.The optimal lipase-producing conditions of Pseudomonas sp.26-2 were investigated through orthogonal test.Result： The results were： 1.5% starch as carbon source, 3% yeast extract as nitrogen source, 0.05% Mg2SO4·7H2O,K2HPO4 0.2%, 0.2% olive oil; the initial pH was 7.0, and optimal temperature for fermentation was 30 ℃. In this condition, the lipase activity reached 15.5U/ml. Conclusion： The strain has some extent of lipase - producing ability, which has laid a foundation of microbial mutation and lipase - producing recombinant strains.