乳化体系中脂肪酶催化合成环十五内酯

对筛选的假丝酵母菌株Candida.sp.GXU08所产脂肪酶催化15-羟基十五烷酸甲酯合成环十五内酯进行了研究,使用超声震荡将脂肪酶酶液分散到环己烷中,以此形成水/有机溶剂乳化体系,考察了不同因素对环十五内酯产量的影响。实验结果表明,在水/环己烷乳化体系中,脂肪酶催化15-羟基十五烷酸甲酯合成环十五内酯的最适条件为:在40℃、180r/min的条件下,1g脂肪酶(pH=7.0)催化8mmol/L的15-羟基十五烷酸甲酯反应72h,单位酶活生成环十五内酯的最大质量为47.77×10-3mg,是在纯有机溶剂环己烷中单位酶活生成环十五内酯最大质量14.54×10-3mg的3.285倍。反应后的脂肪酶重复使用1次能大大提高环十五内酯的生成量。直接使用一定浓度的酶液代替酶粉催化合成环十五内酯具有转化率高、省时、节能等优点。

Synthesis of Cyclopentadecanolide by Catalyzed Lipase in Emulsion System

A screened lipase from Candida sp.GXU08 strain was used to catalyze the synthesis reaction of cyclopentadecanolide from methyl 15-hydroxy-pentadecanate. The lipase solution was dispersed in cyclohexane by ultrasonication to form an aqueous/organic solvent emulsion system. Different effects of reaction conditions on the production of cyclopentadecanolide were studied. The maximal production of cyclopentadecanolide was 47.77×10~(-3) mg/U in the emulsion system under the reaction conditions:40 ℃,180 r/min,1 g lipase solution(pH=7.0),8 mmol/L substrate,72 h. The production in the emulsion system was 3.285 times of that 14.54×10~(-3) mg in cyclohexane organic system. It was also found that reusing the lipase once would greatly increase the production of cyclopentadecanolide. So the lipase powder could be replaced by lipase solution to catalyze the synthesis of cyclopentadecanolide,which could enhance the conversion of the reaction,save time and reduce the use of energy.