THE CARBOHYDRATE OF HUMAN SEMEN

Abstract

SUMMARY The carbohydrates of human semen are partly dialysable and ethanol-soluble, and partly non-dialysable and ethanol-insoluble. The dialysable and ethanol-soluble portion contains fructose as the principal free sugar, and, in addition, inositol, sorbitol, glucose, ribose, fucose, small amounts of certain other sugars and a polysaccharide which, on acid hydrolysis, yields mannose, fucose and amino sugar. The non-dialysable and ethanol-insoluble portion is even richer in polysaccharide material. It contains, in a bound form (g./100 ml. semen): 0·2 amino sugar, 0·1 sialic acid, and 0·4 orcinol-reactive carbohydrate material which on acid hydrolysis yields galactose, mannose, and fucose, but only a trace of glucose. On incubation of human semen at room temperature, a proteolytic breakdown of seminal proteins sets in, accompanied by a release of carbohydrate in an ethanol-soluble form. Glycogen occurs in human semen in traces only.