Dimethylolurea as a tyrosine reagent and protein protectant against ruminal degradation

Preparation and physicochemical properties of glycosylated derivatives of pea legumin

“…studied with a large excess of carbohydrate in the reaction medium buffered at pH 8.5, where the cyanoborohydride anion selectively reduces the Schiff base formed between the carbonyl groups of reducing sugars and protein-free amino groups (Borch et al, 1971). Since it has been shown that the hydroxyl groups could react with tyrosine side chains (Friedman et al, 1982), we have verified, by amino acid analysis, that only the amino groups were effectively modified by glycosylation under our experimental conditions. Both the number of carbohydrate residues covalently bound to legumin and the number of remaining amino groups were determined to evaluate the progress of the reaction.…”

Inhibition of browning by sulfur amino acids. 1. Heated amino acid-glucose systems

“…In the presence of a thiol, the aldehyde can com-R-CHO + R'-NH2 £ R-CH(OH)N+H2-R' Our results indicate that SH-containing amino acids such as cysteine, iV-acetylcysteine, and reduced glutathione are nearly as effective as sodium bisulfite in preventing nonenzymatic browning of heated amino acid-glucose mixtures. Urea is less effective, but it may be of special value in feed products for animal consumption, where it can also serve as a nutritional source of nitrogen for ruminants such as cattle and sheep (Friedman et al, 1982b).…”

Nutritional Value of Proteins from Different Food Sources. A Review

“…The utilization of food protein by ruminants is often enhanced by heat treatment, which can lessen protein breakdown by bacteria in the rumen (Friedman et al, 1982b). To optimize such heat treatments for soybeans, Faldet et al (1992) measured available lysine in vitro and in vivo.…”