Products from the Fermentation of Glucose and Arabinose by Butyric Acid Anaerobes

Abstract

Fermentation of glucose by 52 strains of butyric acid-producing anaerobes and related types was studied with respect to formation of acid and neutral products (butyl, ethyl and isopropyl alcohols and acetone). All of the butyric types (49 cultures) produced butyl and ethyl alcohols; most of them, acetone; and some, isopropyl alcohol. Low yields of neutral products were generally associated with high final acidity. When isopropyl alcohol replaces acetone as a product, the oxidation-reduction relationship is partially balanced by reduced production of butyl alcohol. The fact that ethyl alcohol production was usually close to normal, regardless of acidity, leads to the conclusion that this substance is formed by a simpler mechanism than is butyl alcohol or acetone. Arabinose was only poorly fermented as compared to glucose, with greatly reduced yield of neutral products and high final acidity. The 2nd group (3 cultures of the facultative anaerobe, Clostridium polymyxa type) gave butylene glycol and acetyl-mcthyl carbinol as characteristic products.