【目的】以紫苏籽油为原料,研究脂肪酶催化紫苏籽油与甘油合成甘油二酯的工艺条件。【方法】在无溶剂体系下,以Lipozyme RM IM为催化剂,采用响应面分析法对甘油解反应的工艺条件进行研究和优化。【结果】得到甘油解反应的最佳条件为底物摩尔比(甘油﹕紫苏籽油)=1﹕1.5,加酶量11.8 wt%,反应温度72℃,反应时间14.5 h。在此最优反应条件下得到的产物中甘油二酯含量为54.33%,甘油三酯含量为26.20%,纯化后的甘油二酯油的理论纯度达到67.47%,α-亚麻酸的含量达到52.26%。【结论】影响甘油解反应的显著因素为底物摩尔比、加酶量、反应温度和反应时间,底物摩尔比与加酶量的交互作用最显著。
【Objective】Lipase-catalyzed synthesis of DAG production between perilla seed oil and glycerol was studied.【Method】Response surface methodology was used to optimize the reaction conditions of glycerolysis by Lipozyme RM IM in a solvent-free system.【Result】The optimal parameters were as follows: substrate molar ratio of glycerol to perilla seed oil was 1﹕1.5,enzyme load was 11.8 wt%,reaction temperature was 72℃,and reaction time was 14.5 h.Under the optimal conditions,DAG content could reach 54.33% in the reaction product,and TAG content lowered to 26.20%.The theoretical purity of DAG oil could reach 67.47% after purification by distillation,and the content of α-linolenic acid reached 52.26% in the DAG oil.【Conclusion】Substrate molar ratio of glycerol to perilla seed oil,enzyme load,reaction temperature and reaction time were all significant factors,and the interaction between substrate molar ratio and enzyme load was the most significant.