Biomedical subjects

M J Longacre

Publications and source records attributed to M J Longacre.

2 recordsLinked to original sources

PubMed1989

Recovery of soluble dietary fiber is dependent on the method of analysis.

The effects of different methods on the distribution of total neutral sugars (TNS), uronic acids (UA), and beta-glucans (beta G) between the soluble (S) and insoluble (I) fractions of dietary fiber (DF) were determined for peas, kidney beans, oat bran, rice, and macaroni. Incorporation of a protease step into the Theander method "A" modestly increased, and addition of a pepsin digestion further increased the proportion of total fiber recovered in the S fraction. The effect of extraction method on the distribution of TNS, UA, and beta G between the S and I fractions varied with the food. The three methods measured the same total DF in a food and 1-3% starch in the I fraction of peas and kidney beans. Use of dimethyl sulfoxide to solubilize starch, or elevated temperature to extract S components, had no effect on the distribution of DF between S and I fractions of peas and macaroni. Incomplete protein hydrolysis did not always lower Klason lignin and excluding lignin from the fiber complex did not always substantially increase the S fraction.

Dietary Carbohydrates↗

PubMed1988

Oat fiber: composition versus physiological function in rats.

The effect of processing on the ability of oat fiber to lower plasma and liver cholesterol concentrations in rats was studied. Male Sprague-Dawley rats were fed diets containing 6% dietary fiber as cellulose, oat bran, high fiber oat flour or one of four processed high fiber oat flours for 3 wk. All diets also contained 1.0% cholesterol and 0.2% cholic acid. At the conclusion plasma and liver concentrations of cholesterol and triglycerides were measured. All of the oat products significantly lowered plasma and liver cholesterol without depressing food intake or weight gain. As little as 4% dietary fiber in a processed oat flour significantly lowered cholesterol concentrations. Detailed fiber analysis of all of the oat fiber products revealed that processing increased the proportion of the total fiber that was soluble. The proportions recovered as total beta-glucans and total neutral sugars also increased, in part because the proportion recovered as Klason lignin decreased in all of the processed oat flours except the one prepared by a high pressure extrusion process.

Animals↗