Abstract: Disclosed is a whitening cosmetic composition comprising .gamma.-L-glutamyl-L-cystine, .gamma.-L-glutamyl-L-cysteine disulfide, oxidized glutathione or a derivative thereof, the amino group of which is acylated with an alkanoyl group or an aroyl group. The whitening cosmetic composition of the present invention have extremely good in water solubility and heat stability and stability during storage and show a melanin formation inhibitory activity against melanoma cells without any cytotoxicity.

Abstract: A preservative for plants is described whose active ingredient(s) are the compounds selected from the group consisting of olefin compounds and salts and esters thereof, N-(2-chloro-4-pyridyl)ureas, dipicolinic acid and derivatives and salts thereof, epoxy compounds and salts and esters thereof, and SH-reagents. The preservative is usable for keeping the freshness of plants, in particular fruits, vegetables and cut flowers, and cut flowers for a long period of time.

Abstract: A preservative for plants is described whose active ingredient(s) are the compounds selected from the group consisting of olefin compounds and salts and esters thereof, N-(20chloro-4-pyridyl)ureas, dipicolnic acid and derivatives and salts thereof, epoxy compounds and salts and esters thereof, and SH-reagents. The preservative is usable for keeping the freshness of plants, in particular fruits, vegetables and cut flowers, and cut flowers for a long period of time.

Abstract: The present invention relates to nutrient compositions for mammals comprising L-glutamyl-L-glutamine.

Abstract: A preservative for plants is described whose active ingredient(s) are the compounds selected from the group consisting of olefin compounds and salts and esters thereof, N-(2-chloro-4-pyridyl)ureas, dipicolinic acid and derivatives and salts thereof, epoxy compounds and salts and esters thereof, and SH-reagents. The preservative is usable for keeping the freshness of plants, in particular fruits, vegetables and cut flowers, and cut flowers for a long period of time.

Abstract: Nutrient compositions useful as amino acid infusions comprise L-glutamyl-L-cystine and/or L-glutamyl-L-cysteine disulfide. The nutrient compositions can achieve extremely high utilization of cysteine and cystine which could not be hitherto used as nutrient compositions.

Abstract: Disclosed is a feed composition for culturing fishes, which comprises a peptide represented by the general formula (I): ##STR1## wherein Cys-Cys means a disulfide linkage of cysteinyls; each of R.sub.1, R.sub.2, R.sub.3 and R.sub.4 independently represents .gamma.-L-glutamyl or glycyl; each of m,n,p and q is an integer of 0 or 1, provided that m,n,p and q are not simultaneosuly 0; and a conventionally formulated fish feed.The peptide in the feed composition is effective in treating and preventing hepatic disorders of cultured fishes.

Abstract: A process for improving the quality of whey protein, characterized by maintaining whey protein solution at a pH of from 8.5 to 11.5 and a temperature of from 35.degree. to 50.degree. C., adding to the solution a mixture of at least one acid selected from citric acid, phosphoric acid, polyphosphoric acids, phytic acid and oxalic acid with at least one acid selected from hydrochloric acid, sulfuric acid, lactic acid, tartaric acid, succinic acid and maleic acid so as to adjust the pH of the solution to 6-8. By the process of this invention, it is possible to obtain a whey protein having improved brittleness and excellent bending strength.