An in vitro assay for assessing the effects of dietary components such as fiber on lipase-catalyzed hydrolysis of long-chain triacylglycerols

Abstract

An in vitro method to determine rates of pancreatic lipase-catalyzed hydrolysis of long-chain triacylglycerols is reported. This assay is designed to simulate more closely than do existing in vitro assays, conditions that prevail in the human duodenum. This assay is potentially useful for rapidly determining rates of lipolysis as influenced by lipid type and by various dietary components such as fiber. Included in the assay mixture are olive oil, lipase, colipase, emulsifiers (Span 60^TM, Tween 60^TM), buffer solution (2-[N-morpholino]ethanesulfonic acid), pH 6.5, four bile salts, calcium and sodium. The reaction is conducted at 37d`C and 150 rpm. Appropriate emulsion stability and particle size are achieved by sonification. The assay procedure was validated with respect to stopping the reaction, recovery of known amounts of added oleic acid and precision.