title: [A fluorometric method of determining cholesterol esterase activity].
abstract: A simple and highly specific method for estimating the cholesterol esterase activity is suggested. Cholesterol esterase (EC 3.1.1.13) is incubated with the emulsified substrate, cholesteryl-o-coumarate, at pH 6.6 to yield o-coumaric (trans-2-hydroxycinnamic) acid detected fluorimetrically (lambda exc 363 nm, lambda em 494 nm) at pH 10.4. The fluorescence associated with the unhydrolyzed substrate is negligible. Cholesteryl-o-coumarate is not hydrolyzed by pancreatic lipase, trypsin, or chymotrypsin under the above conditions. About 1 microgram of pancreatic cholesterol esterase can be determined upon 15 min incubation. The substrate was synthesized by condensation of o-acetoxy-trans-cinnamic acid with cholesterol using the di-tert-butyl pyrocarbonate--pyridine--4-dimethylaminopyridine system.
authors.forename: V F
authors.initials: VF
authors.lastname: Pozdnev
authors.forename: K S
authors.initials: KS
authors.lastname: Planutis
authors.forename: A I
authors.initials: AI
authors.lastname: Tochilkin
mesh_terms: D000818:Animals; D002788:Cholesterol Esters / Q000378:metabolism; D002802:Cholinesterases / Q000378:metabolism*; D002918:Chymotrypsin / Q000378:metabolism; D003373:Coumaric Acids / Q000378:metabolism; D006868:Hydrolysis; D007700:Kinetics; D010179:Pancreas / Q000201:enzymology; D013050:Spectrometry, Fluorescence; D002787:Sterol Esterase / Q000378:metabolism; D013379:Substrate Specificity; D013552:Swine; D014357:Trypsin / Q000378:metabolism
chemical_list: D002788:Cholesterol Esters; D003373:Coumaric Acids; D002787:Sterol Esterase; D002802:Cholinesterases; D002918:Chymotrypsin; D014357:Trypsin
vernacular_title: Fluorometricheskiĭ metod opredeleniia aktivnosti kholesterolesterzy.