合成己酸乙酯脂肪酶产生菌的筛选及发酵条件的研究

Studies on Selection of Lipase-producing Strains and Synthesis of Ethyl Caproate

以有机相中合成酶活为指标,通过对薰衣草根际土壤产脂肪酶菌株的筛选,获得了一株在有机相中合成己酸乙酯转化率相对较高的细菌Arthrobacter Y-605,其己酸乙酯转化率为67.53%。考察了影响该菌株产脂肪酶的各项因素,确定其最佳培养基组分:2%玉米粉,1%黄豆粉,0.1%尿素,0.05%MgSO4,0.1%K2HPO4,0.15%KCl;最适培养条件:初始pH8.0,温度为和35℃,装液量60 ml,转速为160 r/min;同时,表面活性剂Tween80的添加对脂肪酶的产生具有促进作用。通过对Arthrobacter Y-605培养条件的优化,脂肪酶活力由3.8 U/ml提高到13.33 U/ml,为该菌株的菌种改良及其在有机相合成领域的应用奠定了基础。

A sort of lipase producing strain with relatively high esterification rate of ethyl hexanoate was obtained was isolated from Lavandula vera L. root soil. The strain was identified and named as A rthrobacter Y-605. The optimal lipase producing conditions of the strain was indicated in details and the results were as follows：2% maize meal,1% soy flours,0.1% urea,0.05%MgSO4,0.1% K2HPO4,0.15% KCl. The most optimal initial pH value were 8.0 and the temperature and 35℃. The maximum yield was obtained when A rthrobacter Y-605 was shake-cultivated with liquid volume of 60 ml and rotation speed of 160 r/min. The surface active agent Tween80 which can increese lipase production was proved. Through the optimization of fermentation conditions to Arthrobacter Y-605,the lipase production was improved from 3.8 U/ml to 13.33 U/ml,which also has laid a foundation of microbial mutation and application in organic synthesizes.