Initial Studies on the Extraction of the Active Substance Inducing Monocoitic Behavior in House Flies, Black Blow Flies, and Screw-Worm Flies123

Abstract
A monocoitic substance extracted from male house flies, Musca domestica L., the black blow fly, Phormia regina (Meigen); and the screw-worm fly, Cochliomyia hominivorax (Coquerel), prevented mating when it was injected into virgin female house flies. The active substance present in the male house fly and screw-worm fly can be extracted with water, methanol, and 95% ethanol. It is more soluble in methanol than in absolute ethanol, and it is insoluble in diethyl ether and chloroform. Dialysis and chromatography on Sephadex® indicated mat it has a low molecular weight. The activity of extracts from the male house fly was not reduced by heating in a boiling water bath for 2 min. Thus, the substance is polar, of a relatively small molecular weight, and not a lipid or protein.