title: Optimizing the molecular weight of oat β-glucan for in vitro bile acid binding and fermentation.
abstract: A previous study showed β-glucan with low molecular weight (MW, 1.56×10(5) g/mol) bound more bile acid and produced greater amounts of short-chain fatty acids (SCFA) than did β-glucan with high MW (Mn=6.87×10(5) g/mol). In the current study, β-glucan extracted from oat flour was fractionated into six different MW levels (high MW, 7.09×10(5); low level 1 (L1), 3.48×10(5); L2, 2.42×10(5); L3, 1.61×10(5); L4, 0.87×10(5); and L5, 0.46×10(5) g/mol) and evaluated to find the optimum MW affecting in vitro bile acid binding and fermentation. The β-glucan fractions with 2.42×10(5)-1.61×10(5) g/mol (L2 and L3) bound the greatest amounts of bile acid. After 24 h of fermentation, no differences were found in total SCFA formation among L1, L2, L3, and L4 fractions; however, the high MW and L5 MW fractions produced lower amounts of total SCFA. Thus, the optimum MW of β-glucan to affect both hypocholesterolemic and antitumorigenic in vitro effects was in the range of 2.42×10(5)-1.61×10(5) g/mol. This MW range also was the most water-soluble among the MWs evaluated.
authors.affiliation: Department of Food Science and Human Nutrition, Iowa State University, Ames, Iowa 50011-1061, United States.
authors.forename: Hyun Jung
authors.initials: HJ
authors.lastname: Kim
authors.forename: Pamela J
authors.initials: PJ
authors.lastname: White
mesh_terms: D018554:Avena / Q000737:chemistry*; D001647:Bile Acids and Salts / Q000378:metabolism*; D005232:Fatty Acids, Volatile / Q000032:analysis / Q000378:metabolism; D005285:Fermentation; D008970:Molecular Weight; D047071:beta-Glucans / Q000737:chemistry* / Q000378:metabolism*
chemical_list: D001647:Bile Acids and Salts; D005232:Fatty Acids, Volatile; D047071:beta-Glucans