Gas chromatographic analysis of amines and other compounds produced by several species of Clostridium

Abstract

Procedures are described for the routine analysis of amines and other compounds produced in bacterial cultures. Whole cultures were grown in six mls of chopped meat-glucose medium, acidified, and extracted with ethyl ether or chloroform to obtain organic acids, alcohols, ketones, aldehydes, and other neutral compounds. The residual broth was then made basic and extracted with chloroform to obtain the amines. For chromatographic analyses, alcohols and amines were converted to trifluoroacetyl derivatives. Organic acids were converted to their methyl esters. Analyses were made by a temperature- programmed gas chromatograph equipped with flame ionization detectors.

Sixty-two strains of clostridia, representing 13 species, were analyzed for soluble products in whole cultures. Many amines were found and total amine concentrations exceed 0.5% (weight) in cultures of several species examined. Neutral products were found to be major products of several species. Alcohols both short and long chain were detected and were valuable in differentiation of some groups of clostridia.

The 13 species were grouped as follows: on the basis of fatty acids and neutral products, 7 groups; on the basis of amine products, 10 groups; on the basis of alcohol and neutral products, 12 groups; and on the basis of amine, alcohol, and neutral products, 13 groups.