In vitro bile-acid binding and fermentation of high, medium, and low molecular weight beta-glucan.
The impact of beta-glucan molecular weight (MW) on in vitro bile-acid binding and in vitro fermentation with human fecal flora was evaluated. beta-Glucan extracted from oat line 'N979-5-4' was treated with lichenase (1,3-1,4-beta-D-glucanase) to yield high (6.87x10(5) g/mol), medium (3.71x10(5) g/mol), and low (1.56x10(5) g/mol) MW fractions. The low MW beta-glucan bound more bile acid than did the high MW beta-glucan (p<0.05). If the positive control, cholestyramine, was considered to bind bile acid at 100%, the relative bile-acid binding of the original oat flour and the extracted beta-glucan with high, medium, and low MW was 15, 27, 24, and 21%, respectively. Significant effects of high, medium, and low MW beta-glucans on total SCFA were observed compared to the blank without substrate (p<0.05). There were no differences in pH changes and total gas production among high, medium, and low MW beta-glucans, and lactulose. The low MW beta-glucan produced greater amounts of SCFA than the high MW after 24 h of fermentation. Among the major SCFA, more propionate was produced from all MW fractions of extracted beta-glucans than from lactulose. In vitro fermentation of extracted beta-glucan fractions with different MW lowered pH and produced SCFA, providing potential biological function.
Kim
Hyun Jung
HJ
Department of Food Science and Human Nutrition, Iowa State University, Ames, Iowa, USA.
White
Pamela J
PJ
D018554:Avena / Q000737:chemistry*; D001419:Bacteria / Q000378:metabolism; D001647:Bile Acids and Salts / Q000737:chemistry*; D005243:Feces / Q000382:microbiology; D005285:Fermentation; D006801:Humans; D008954:Models, Biological; D008970:Molecular Weight; D010936:Plant Extracts / Q000737:chemistry* / Q000378:metabolism; D047071:beta-Glucans / Q000737:chemistry* / Q000378:metabolism
D001647:Bile Acids and Salts; D010936:Plant Extracts; D047071:beta-Glucans