以精炼菜籽油为底物,通过酶法甘油解制备甘油二酯,比较了3种常用固定化脂肪酶甘油解制备甘油二酯的能力.结果表明:Lipozyme(@)RM IM具有较好的甘油耐受性,采用甘油预吸附的方式进行甘油解反应,可明显减少反应中酶活损失,显著提高酶的重复使用寿命.在菜耔油与甘油摩尔比1∶1,酶添加量为油质量的5％,硅胶与甘油质量比1∶1,反应温度60℃的优化条件下,甘油解反应8h后,产物中的甘油二酯含量达到57.5％.通过硅胶预吸附甘油可以使Lipozyme(@)固RM IM酶的多批次操作稳定性得到很大提高,半衰期达到22次,有应用于工业生产的潜力.%Diacylglycerol was synthesized by enzymatic glycerolysis using refined rapeseed oil as substrate. Three commercial immobilized lipases for preparing diacylglycerol were compared. The results showed that Lipozyme? RM IM had a good glycerol tolerability. Useful life of the lipase could be remarkably improved using glycerol preadsorbed by silica gel. Diacylglycerol content of the product was 57. 5% after 8 h reaction under the optimum conditions: molar ratio of rapeseed oil to glycerol 1: 1, enzyme dosage 5% (based on the mass of rapeseed oil) , mass ratio of silica gel to glycerol 1:1, reaction temperature 60 °C. The enzyme could be used 22 times repeatedly in batch process, which had a potential for industrial production.
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