Carnitine Acyl Esters of Human Semen

Carnitine derivatives, including short‐chain acylcarnitines, were detected in human semen by a bioautographic method using a carnitine requiring mutant of the yeast, Torulopsis bovina . Acylcarnitines formed approximately 55% of the total carnitine content of semen from fertile males, whereas the acylcarnitine fraction of semen from infertile males comprised only 25%, and that of postvasectomy semen comprised 65%. Gas chromatographic analysis of the fatty acids liberated from acylcarnitine derivatives demonstrated the presence of acetyl, propionyl, isobutyryl, butyryl, and isovaleryl derivatives in postvasectomy semen and semen from fertile and infertile males.