Metabolic transformations of U-C-14-resistant and U-C-14-gelatinized bean starch in rat liver and body

The metabolic fate of carbon derived from dietary U-C-14-resistant (RS) and U-C-14-gelatinized (GS) bean starches was studied in rat-liver and body (mainly muscle). Male Wister Hans rats were fed 20 mg of either GS (43.3 x 10(3) Bq) or RS (47.3 x 10(3) Bq) by gavage. The incorporation of C-14 was measured in the amino acid, lipid, and glycogen fractions of the liver and carcass. The substitution of U-C-14-gelatinized starch with U-C-14-resistant starch provided the body with C-14 incorporated mainly into proteins and to a lesser extent into lipids in both liver and carcass. Glutamic and aspartic acids sind alanine were the amino acids with highest-incorporation of C-14 in the liver. Feeding of U-C-14-resistant starch led to a high radioactivity in the phospholipid, cholesterol, and triacylglycerol fractions in the liver and to a lesser extent in cholesterol and the free fatty acids fraction in carcass.