ABSTRACT

A true lipase catalyzes the hydrolysis of triacylglycerols (TAG). In seeds, lipase controls the first step in TAG mobilization, and thus it may control the rate of germination. This chapter deals with the true lipases (E.C. 3.1.1.3) in oilseeds. It also deals with a group of apparently similar enzymes occurring in diverse tissues that possess the combined activities of phospholipases A1 (E.C. 3.1.1.32), A2 (E.C. 3.1.1.4), B (E.C. 3.1.1.5), glycolipase, sulfolipase, and monoacylglycerol lipase. The chapter then reviews the plant lipases include those on cereal lipases, plant lipases, and oil bodies with details on lipase assays. True lipases, which attack the fatty acyl linkage of water-insoluble TAG, are known to occur in oilseeds and cereals. In the study of lipases, technical difficulties in the assay of enzyme activities need to be overcome. Some of the difficulties are not unusual and are common among enzyme assays dealing with water-insoluble substrates.