Isolation and indentification of amino acid derivatives from yeast

Abstract

439are distributed in all of the foods investigated. It is interesting to point out that mushrooms and beans contained appreciable amounts of spermidine because mutagenicity of the nitrosamines formed from spermidine has been proved as described previously. To our knowledge, this finding of the presence of large amounts of spermidine in mushrooms was not reported in the literature.From this study, it was concluded that the accurate measurements of di-and polyamines in foods can be achieved by using GLC after derivatization. Due to simplicity and reproducibility of the derivative formation reaction, and stability of the derivatives formed, the method reported herein appears to be adequate for both qualitative and quantitative analps of diand polyamines in foods, although requiring ion-exchange chromatographic purification.

Amino Acid Metabolism by Yeasts and Lactic Acid Bacteria during Bread Dough Fermentation

“…Their specific hydrolytic action on dough proteins during fermentation release amino acids and peptides. The microbial mass of microorganisms can also supply low molecular weight nitrogen metabolites by cellular lysis (Thorn, 1971;Rothenbuehler et al, 1982;Collar et al, 1991a). The release of amino acids and peptides by enzymatic reactions (MacWilliams and Clapperton, 1969;Spicher and Nierle, 1984a) and by metabolism of sugars (Okuhara and Harada, 1971) and other components (Nisbet and Payne, 1979), stimulates or inhibits the synthesis of proteases of some species of streptococci (Westhoff and Cowman, 1970).…”