TRIGLYCERIDE SPECIFICITY OF CANDIDA-CYLINDRACEA LIPASE - EFFECT OF DOCOSAHEXAENOIC ACID ON RESISTANCE OF TRIGLYCERIDE TO LIPASE

Tuna oil was hydrolyzed with Candida cylindracea lipase. After 70% hyd rolysis of the oil, the docosahexaenoic acid (DHA) content in the glyc eride mixture [a mixture of TG (triglyceride), DG (diglyceride) and MG (monoglyceride) was twice that of the original oil. DHA-rich TG and D G were observed, but DHA-rich MG was absent. C. cylindracea lipase see med to have a ''triglyceride specificity,'' and it favors TG without D HA over TG containing DHA. In accordance with this hypothesis, TG cont aining a mixture of oleic acid (OA) and DHA was synthesized and then h ydrolyzed with C. cylindracea lipase. TGs in the hydrolysis product we re fractionated and analyzed quantitatively by high-performance liquid chromatography. Four kinds of TGs were obtained. TG with three molecu les of OA was hydrolyzed most easily. Increasing the DHA content of TG resulted in less hydrolysis of TG. The results suggested that C. cyli ndracea lipase had a TG specificity for the whole structure of TG in p reference to the individual ester bonds; OA coexisting with DHA in TG was resistant to C. cylindracea lipase due to the TG structure.