Effect of Lipase Activity and Specificity on the DAG Content of Olive Oil from the Shodoshima-Produced Olive Fruits

• Published in: Journal of the American Oil Chemists' Society Vol. 85; no. 7; pp. 629 - 633
• Main Authors: Shimizu, Masao, Kudo, Naoto, Nakajima, Yoshinobu, Matsuo, Noboru, Katsuragi, Yoshihisa, Tokimitsu, Ichiro, Barceló, Francisca
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Berlin/Heidelberg : Springer-Verlag 01.07.2008; Springer-Verlag; Springer; Springer Nature B.V
• Subjects: Acidity; acylglycerols; Agriculture; Biological and medical sciences; Biomaterials; Biotechnology; chemical composition; Chemistry; Chemistry and Materials Science; Diacylglycerol; diacylglycerols; enantiomers; Enantioselectivity; enzymatic hydrolysis; Fat industries; Fatty acids; Food industries; Food Science; free fatty acids; Fruit and vegetable industries; Fruits; Fundamental and applied biological sciences. Psychology; Hydrolysis; Inactivation; Industrial Chemistry/Chemical Engineering; Islands; Isomerization; Lipase; monoacylglycerols; Olea europaea; Olive fruit; Olive oil; olives; Original Paper; storage temperature; Temperature; triacylglycerol lipase; Japan; Hydrolysis; Olive fruit; Enantioselectivity; Lipase; Isomerization; Diacylglycerol; Olive fruit . Lipase; Fruit; Enzyme; Oil content; Triacylglycerol lipase; Lipids; Esterases; Vegetable oil; Olive oil; Edible oil; Carboxylic ester hydrolases; Oils and fats industry; Olive; Specificity; Hydrolases; Hydrolysis . Isomerization
• ISSN: 0003-021X; 1558-9331
• DOI: 10.1007/s11746-008-1243-9

Olive oils have a higher relative diacylglycerol (DAG) content than other plant oils. The lipase in olive fruits is involved in DAG production and is directly related to the acidity of the olive oil. However, the lipase activity and positional selectivity have not been clarified. To investigate the properties of olive fruit lipase, olive fruits of the Mission variety harvested during mid-December of 2005 on Shodoshima Island (Japan) were stored at 20, 30 or 40 °C for 4 weeks. Changes in the acidity and acylglycerol content of the oils extracted from the stored fruits were analyzed. The acidity and DAG content of the olive oils increased due to triacylglycerol (TAG) hydrolysis during storage. sn-1,2-DAGs preferentially increased during the early stages of storage, indicating that the olive fruit lipase is enantioselective for the sn-3 position, while non-enzymatic isomerization of sn-1,2-DAGs was observed throughout the entire duration of storage. Kinetic analysis revealed that the enantioselectivity of olive fruit lipase for the sn-3 position was approximately four times greater than for the sn-1 position. The lipase was gradually inactivated at temperatures of 30 °C or higher, and the ratios of the rate constant for inactivation to TAG hydrolysis at the sn-3 position was 0.2, 13, and 23 at 20, 30, and 40 °C, respectively.