title: Inhibition of lipase activities by citrus pectin.
abstract: The oral administration of pectin to rats reduced and delayed the peak plasma triacylglycerol concentration. Pectin inhibited the hydrolysis of trioleoylglycerol emulsified with soybean phosphatidylcholine by pancreatic, carboxylester, and lingual lipases in a concentration-dependent manner. However, the effective concentration of pectin for lingual lipase was 100 times lower than that for pancreatic lipase. Pectin did not inhibit the tributyrin- and p-nitrophenylbutyrate-hydrolyzing activities by pancreatic and carboxylester lipase. When low molecular weight pectin was assayed, pectin at a molecular weight of 90,000 (MW 90) most strongly inhibited three lipase activities. When the effect of pH on pectin inhibition was analyzed using pancreatic lipase, strong inhibition was observed at an acidic pH (below pH 7.0). In the assay system, the pancreatic lipase protein levels in the supernatant and fat layer were estimated by Western blotting with an anti-pancreatic lipase antibody. Pectin reduced the amount of pancreatic lipase protein in the fat layer in a concentration-dependent manner and concomitantly increased that in the supernatant. These results suggest that pectin may interact with emulsified substrates and inhibit the adsorption of lipase to the surface of substrate emulsion.
authors.affiliation: Division of Medical Bioscience, Department of Bioscience, Integrated Center for Sciences, Ehime University, Shigenobu, Onsen-gun, Ehime 791-0295, Japan. tsujita@m.ehime-u.ac.jp
authors.forename: Takahiro
authors.initials: T
authors.lastname: Tsujita
authors.forename: Maho
authors.initials: M
authors.lastname: Sumiyosh
authors.forename: Li-Kun
authors.initials: LK
authors.lastname: Han
authors.forename: Tsutomu
authors.initials: T
authors.lastname: Fujiwara
authors.forename: Junji
authors.initials: J
authors.lastname: Tsujita
authors.forename: Hiromichi
authors.initials: H
authors.lastname: Okuda
mesh_terms: D000273:Adipose Tissue / Q000201:enzymology; D000818:Animals; D015153:Blotting, Western; D043182:Carboxylesterase / Q000037:antagonists & inhibitors; D002957:Citrus / Q000737:chemistry*; D003314:Corn Oil / Q000008:administration & dosage; D004655:Emulsions; D004791:Enzyme Inhibitors / Q000494:pharmacology*; D008049:Lipase / Q000037:antagonists & inhibitors*; D008297:Male; D008970:Molecular Weight; D010179:Pancreas / Q000201:enzymology; D010368:Pectins / Q000008:administration & dosage / Q000494:pharmacology*; D051381:Rats; D017208:Rats, Wistar; D013552:Swine; D014059:Tongue / Q000201:enzymology; D014280:Triglycerides / Q000097:blood
chemical_list: D004655:Emulsions; D004791:Enzyme Inhibitors; D014280:Triglycerides; D003314:Corn Oil; D010368:Pectins; D043182:Carboxylesterase; D008049:Lipase