Ɛ-Fructoselysine as an Absorption-delayed Material in the Small Intestinal Lumen of Rats Fed Browned Casein
- 1 November 1978
- journal article
- research article
- Published by Oxford University Press (OUP) in Agricultural and Biological Chemistry
- Vol. 42 (11) , 2071-2076
- https://doi.org/10.1080/00021369.1978.10863309
Abstract
Investigations were carried out in order to elucidate the reason for the nutritive value reduction of browned protein by using casein labeled with U-14C-L-lysine. When the browned casein was ingested by growing rats, high radioactivity was found in a lysine derivative present in the small intestinal TCA-soluble fraction obtained 3 and 7 hr after feeding. Experiments were done to identify the lysine derivative as absorption-delayed material. This material was identified by an amino acid auto-analyzer, paper chromatography and radioactive analysis as l-deoxy-l-(Ɛ-N-L-Iysino)-D-fructose (Ɛ-fructoselysine), which accounted for about 70% of the total radioactivity in the small intestinal TCA-soluble fraction obtained 7 hr after feeding. Lysine which was found after 3 hr, was disappeared from the intestinal TCA-soluble fraction taken 7 hr after feeding, but e-fructoselysine remainded. Its content as acetate found 7 hr after one-dosal feeding of 600 mg browned labeled casein (700,000 dpm) was 18.3 and 19.0 mg/each rat, respectively. These values accounted for about 40% of the lysine content in the ingested browned casein.This publication has 0 references indexed in Scilit: