超临界CO_2体系中磷脂酶A_2催化合成高DHA含量DHA-PC的研究

Catalytic synthesis of DHA-PC with high DHA contents by phospholipase A_2 in supercritical CO_2 system

以南极磷虾粉为原料,乙醇浸提后分离纯化得到的精制磷脂酰胆碱的纯度高达90.8%,以此为原料,在超临界CO_2体系中使用磷脂酶A_2(PLA_2)催化磷脂酰胆碱(PC)Sn-2位脂肪酸水解,使游离DHA结合到Sn-2位以制备高DHA含量的磷脂酰胆碱(DHA-PC),并研究了不同参数对该反应的影响。最佳酶解反应条件分别如下:固定化PLA2的添加量15%(占总底物),时间6 h,温度55℃,压力12 MPa。在此条件下,南极磷虾磷脂酰胆碱上DHA的含量可达62.3 mol%。由此得出结论,PLA_2用于磷脂酰胆碱改性以制备DHA-PC的可行性高。

With the raw material of euphausia superba powder,the purity of the refining phosphatidylcholine gained by ethyl alcohol extraction and separation and purification reached 90.8%,then the refining phosphatidylcholine was used as raw material and phospholipase A_2 was used to catalyze the fatty acid hydrolysis of Sn-2 position of phosphatidylcholine in supercritical CO_2 system to make the fish oil DHA to Sn-2 position and form the DHA-PC with high DHA contents.Meanwhile,the effects of different parameters on the reaction were surveyed.The results showed that,the best additive amount of immobilization phospholipase A_2 was 15%（ occupied the total substratio）,the best enzymolysis was 6 h,the best enzymolysis temperature was 55 ℃,the best enzymolysis pressure was 12 MPa,respectively.Under such condition,the DHA binding ratio of euphausia superba phosphatidylcholine could reach 62.3 mol%. And it could be concluded that immobilization phospholipase A_2 is highly viable for phosphatidylcholine modification to prepare DHA-PC.