The Production of Methyl Mercaptan by Fecal Bacteria Grown on a Peptone Medium

It is surprising that almost no systematic study has been devoted to methyl mercaptan, a common product of the putrefactive cleavage of proteid, in its relation to intestinal putrefaction. Nencki, 1 who discovered this substance among the products of putrefaction, obtained a small amount of it from a large quantity of human feces, and reached the conclusion that it is a usual product of intestinal putrefaction. This conclusion is probably correct, although, strictly speaking, it does not appear fully justified by Nencki’s observations, for the reason that the material used by him could not have been sufficiently fresh to exclude mercaptan formation during a period of exposure to the air. Working with smaller quantities of material than were employed by Nencki, I have never been able to obtain more than a trace of mercaptan (probably the methyl compound), and have usually been able to obtain no evidence whatever of its presence in fresh human material, whether from presumably normal persons or from such as were suffering from intestinal disturbance. But the failure to find mercaptan in the contents of the lower bowel does not prove that this substance has not been formed, for it is possible and even likely that there is some mercaptan production in higher portions of the large intestine, where it is certain that the gas would be readily absorbed. As it appeared that something of interest might be learned from the study of the ability of fecal bacteria from various sources to form mercaptan when growing on a medium which does not readily yield this compound, a considerable number of experiments were made with suspensions of the mixed fecal bacteria from different persons. After growing the bacteria in a two per cent. peptone solution for twenty-four hours at the temperature of 1 Momtsh. f. Chem., x, p. 862, 1889. Das Methylmercaptan als Bestandtheil der menschlichen Darmgase.