Ultrasonic pretreatment for lipase-catalyed synthesis of phytosterol esters with different acyl donors
Ultrasonic pretreatment for lipase-catalyed synthesis of phytosterol esters with different acyl donors
复制标题
超声预处理脂肪酶催化不同酰基供体合成植物甾醇酯
DOI：
10.1016/j.ultsonch.2012.02.004
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发表时间：
2012-09-01
影响因子：
8.4
通讯作者：
Zheng, Chang
中科院分区：
文献类型：
--
作者：
Zheng, Ming-Ming;Wang, Lian;Zheng, Chang
研究了在超声辐射下，以脂肪酶99-125为催化剂，不同酰基供体与植物甾醇进行酯化反应，制备相应的植物甾醇酯。确定了超声波频率为35 kHz，功率为200 W，时间为1 h，以保证令人满意的酯化程度和脂肪酶活性。研究了温度、底物浓度和摩尔比对反应的影响。在异辛烷体系中，当温度为60 ℃，植物甾醇浓度为150 μ mol/mL，植物甾醇与脂肪酸的摩尔比为1：1.5时，植物甾醇酯的转化率可达85.7%以上，反应时间较短（8h）。在超声辐射下，植物甾醇酯与三酰甘油发生酯交换反应，转化率可达90.3%以上。在最佳工艺条件下，超声波预处理的总酯化反应速率是机械搅拌法的2倍以上，且不影响脂肪酶的活性。(C)2012爱思唯尔有限公司版权所有。
This study is focused on the enzymatic esterification of phytosterols with different acyl donors to produce the corresponding phytosterol esters catalyzed by Canadia sp. 99-125 lipase under ultrasound irradiation. An ultrasonic frequency of 35 kHz, power of 200 W and time of 1 h was determined to guarantee satisfactory degree of esterification and lipase activity. The influence of temperature, substrates concentration and molar ratio was investigated subsequently. The optimum production was achieved in isooctane system at 60 degrees C with phytosterol concentration of 150 mu mol/mL and phytosterol to fatty acid molar ratio of 1:1.5, resulting in a phytosterol esters conversion of above 85.7% in short reaction time (8 h). Phytosterols esters could also be converted in high yields to the corresponding long-chain acyl esters via transesterification with triacylglycerols (above 90.3%) under ultrasound irradiation. In optimum conditions, the overall esterification reaction rate using the ultrasonic pretreatment process was above 2-fold than that of mechanical stirring process without damage the lipase activity. (C) 2012 Elsevier B.V. All rights reserved.