title: Evidence for the existence of a soybean resistant protein that captures bile acid and stimulates its fecal excretion.
abstract: Feeding HMF, an insoluble "high-molecular-weight fraction" from an industrial enzymatic digest of a soy protein isolate, increased the fecal excretion of bile acid concomitant with increased fecal nitrogen. An amino acid analysis revealed that this increased fecal nitrogen could be explained by an increase in the insoluble protein fraction. This suggests the existence of an indigestible protein or peptide that can be called a "resistant protein" in the feces. The presumed resistant protein was rich in hydrophobic amino acids and bound bile acid by hydrophobic interaction. The residual fraction of HMF obtained after in vitro pepsin and pancreatin digestion, showed higher in vitro bile acid-binding capacity and excreted more bile acid in vivo than HMF. Its amino acid composition was similar to that of the feces of rat fed with HMF. These results suggest that the fecal resistant protein with bile acid-binding ability could be derived from the indigestible fraction of HMF.
authors.affiliation: Department of Biological Resource Chemistry, Kyoto Prefectural University.
authors.forename: Noriko
authors.initials: N
authors.lastname: Higaki
authors.forename: Kenji
authors.initials: K
authors.lastname: Sato
authors.forename: Hitoshi
authors.initials: H
authors.lastname: Suda
authors.forename: Tomohiko
authors.initials: T
authors.lastname: Suzuka
authors.forename: Takeo
authors.initials: T
authors.lastname: Komori
authors.forename: Tohru
authors.initials: T
authors.lastname: Saeki
authors.forename: Yasushi
authors.initials: Y
authors.lastname: Nakamura
authors.forename: Kozo
authors.initials: K
authors.lastname: Ohtsuki
authors.forename: Kimikazu
authors.initials: K
authors.lastname: Iwami
authors.forename: Ryuhei
authors.initials: R
authors.lastname: Kanamoto
mesh_terms: D000818:Animals; D001647:Bile Acids and Salts / Q000737:chemistry*; D005243:Feces / Q000737:chemistry*; D008297:Male; D010455:Peptides / Q000302:isolation & purification; D010940:Plant Proteins / Q000737:chemistry* / Q000494:pharmacology; D051381:Rats; D011916:Rats, Inbred F344; D013025:Glycine max / Q000737:chemistry*
chemical_list: D001647:Bile Acids and Salts; D010455:Peptides; D010940:Plant Proteins