Relationship between nonprotein sulfhydryl concentration of seminal fluid and motility of spermatozoa in man

The nonprotein sulfhydryl content of human seminal fluid was measured and an inverse correlation between the -SH titer and the motility of the spermatozoa in the fluid over a 5-hour period was found. The same inverse correlation, with less significance, was shown between the -SH titer and the percentage of active cells, semen quality and volume of ejaculates. No correlation between the -SH concentration and the sperm count was detectable. The nonprotein -SH titer was identified qualitatively and quantitatively as ergothioneine. The concentration in human seminal fluid is 1.5 mg %, a value close to that found in human blood.