Abstract: ω-3 Polyunsaturated fatty acids (PUFAs), such as eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), have some pharmacological and physiological effects on human health. They are mainly from fish oil. The present study was made to enrich PUFAs in glyceride from fish oil by the selective hydrolysis of immobilized lipase. The method of combining adsorption with crosslinking was used for Aspergillus oryzae lipase immobilization. Lipase was immobilized by adsorption onto diatomite at 25℃ for 6 h and then crosslinked with 0.5% glutaraldehyde for 1.5 h. The effects of hydrolysis of fish oil with this immobilized lipase were studied.The optimal temperature was 38℃,optimal rotating speed was 200 r•min^-1, the optimal ratio of oil to water was 1∶1, the optimal amount of lipase was 150 U•(g oil)^-1, and the optimum time for concentrating PUFAs in glyceride was 24 h. The results showed that under this hydrolysis conditions the contents of EPA, DHA and EPA+DHA in glyceride were increased respectively from 3.0% to 7.0% , from 4.3% to 14.5% and from 7.3% to 21.5%.

摘要： 采用吸附与交联相结合的方法固定化米曲霉脂肪酶.脂肪酶固定化的参数条件：载体为硅藻土、吸附温度为25℃、吸附时间为6 h、pH值为7.0 KH₂PO₄-NaOH缓冲液、缓冲液离子强度为0.03 mol•L^-1、给酶量为900 U•（g硅藻土）^-1、交联剂为0.5％戊二醛、交联的时间为1.5 h，所得固定化酶酶活力为247 U•（g载体）^-1，蛋白载量为25 mg•（g硅藻土）^-1，水解鱼油操作半衰期为264 h.固定化脂肪酶富集鱼油中ω-3多不饱和脂肪酸甘油酯的最适条件是：温度38 ℃、油水比为1∶1、加酶量为150U•（g油）^-1、反应转速为200 r•min^-1、最佳富集时间为24 h.在此工艺条件下鱼油中EPA由3.0%提高到7.0%，DHA由4.3%提高到14.5%，EPA+DHA由7.3%提高到21.5%.