Premium
Lipolysis of different oils using crude enzyme isolate from the intestinal tract of rainbow trout, Oncorhynchus mykiss
Author(s) -
Gøttsche Jesper R.,
Nielsen Nina S.,
Nielsen Henrik H.,
Mu Huiling
Publication year - 2005
Publication title -
lipids
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.601
H-Index - 120
eISSN - 1558-9307
pISSN - 0024-4201
DOI - 10.1007/s11745-005-1495-9
Subject(s) - triolein , lipolysis , rainbow trout , lipase , chemistry , trout , fish oil , hydrolysis , glyceride , biochemistry , chromatography , enzyme , triglyceride , food science , biology , fishery , fish <actinopterygii> , fatty acid , adipose tissue , cholesterol
Crude enzyme isolate was prepared from the intestine of rainbow trout. Positional specificity of the crude enzyme isolate was determined from both 1(3)‐ and 2‐MAG products after in vitro lipolysis of radioactive‐labeled triolein. The ratio of 2‐MAG/1(3)‐MAG was 2∶1, suggesting that the overall lipase specificity of the enzyme isolate from rainbow trout tended to be 1,3‐specific; however, activity against the sn ‐2 position also was shown. In vitro lipolysis of four different unlabeled oils was performed with the crude enzyme isolate. The oils were: structured lipid [SL; containing the medium‐chain FA (MCFA) 8∶0 in the sn ‐1,3 positions and long‐chain FA (LCFA) in the sn ‐2 position], DAG oil (mainly 1,3‐DAG), fish oil (FO), and triolein (TO). MCFA were rapidly hydrolyzed from the SL oil. LCFA including n−3 PUFA were, however, preserved in the sn ‐2 position and therefore found in higher amounts in 2‐MAG of SL compared with 2‐MAG of FO, DAG, and TO. Lipolysis of the DAG oil produced higher amounts of MAG than the TAG oils, and 1(3)‐MAG mainly was observed after lipolysis of the DAG oil. The positional specificity determined and the results from the hydrolysis of the different oils suggest that n−3 very long‐chain PUFA from structured oils may be used better by aquacultured fish than that from fish oils.