脂解麻疯树油脂肪酶产生菌的筛选鉴定及其催化特性

Screening and identification of a strain with lipolytic activity against Jatropha oil and its catalytic capacity

摘要:

摘要：【目的】分离筛选具有脂解麻疯树油能力的脂肪酶产生菌株，为以麻疯树油为原料酶法生产生物柴油奠定基础。【方法】以麻疯树油为唯一碳源，从麻疯树种子粉末处理过的土壤中分离筛选出1株具有脂解疯树油能力的脂肪酶产生菌，考察该菌株及其脂肪酶对有机溶剂耐受性以及脂肪酶催化酯化和转酯反应的能力，并通过生理生化特征和16S rDNA序列分析鉴定目的菌株。【结果】菌株LP-2脂肪酶活性为3.03 U/mL，菌LP-2在5%(v/v)甲醇中相对生长量为87.3%，LP-2脂肪酶在10%(v/v)正己烷中相对酶活为80.9%

Abstract:

Abstract: [Objective] To screen lipases applied to biodiesel production, a lipase-producing microorganism was isolated and the enzyme was characterized. [Methods] A strain with lipolytic activity against Jatropha oil was isolated from the soil pretreated by Jatropha curcas L. seed and cultivated on Jatropha oil as sole carbon source. The organic solvent tolerance of the isolated strain and its lipase were measured. The esterification and transesterification catalyzed by the isolated lipase were surveyed. The isolated strain was identified according to the physiological and biochemical characteristics as well as 16S rDNA sequences analysis. [Results] The lipolytic activity of the strain LP-2 was 3.03 U/mL. The relative biomass of strain LP-2 in the media containing 5%(v/v) methanol was 87.3%. The residual activity of LP-2 lipase in 10%(v/v) hexane was 80.9%. LP-2 lipase could catalyze esterification between lauric acid or palmitic acid and n-butanol, n-octanol, dodecanol or glycerol; stearic acid and n-octanol, dodecanol or glycerol; oleic acid and methanol, n-butanol, n-octanol or dodecanol. The transesterification of Jatropha oil with methanol could be catalyzed by LP-2 lipase. Strain LP-2 was identified as Staphylococcus epidermidis and named Staphylococcus epidermidis LP-2. [Conclusion] S. epidermidis LP-2 lipase had the ability to catalyze esterification and transesterification reactions, which suggested that it had potential of producing biodiesel.