INDOLE PROPIONIC ACID-TRYPTAMINE TEST, A NEW USEFUL METHOD IN THE CLASSIFICATION OF CLOSTRIDIA

Abstract

A culture medium containing tryptophan was inoculated with Clostridia species and incubated at 37ªC for 7 days, followed by n-butanol extraction. The extract was evaporated and concentrated in acetone water and then subjected to paper chromatography according to the methods for detecting indole derivatives. Indole propionic acid was produced by almost all of the strains of Cl. sporogenes and Cl. parabotulinum, and tryptamine by most strains of Cl. bifermentans. Except Cl. capitovale, Cl. cadaveris and Cl. aerofoetidum, no other species of Clostridia were found to produce either of them. This new test was more reliable than the Vanillin Violet test used for similar purpose.