The Nutritional Requirements of Lactobacillus pentosus 124-2

Abstract

Biotin, pantothenic acid, and nicotinic acid are needed to satisfy the vitamin requirements of L. pentosus 124-2. No chemically defined medium gave so rapid growth as did a natural medium. One of the best media, containing hydrolyzed casein, required some additions for maximum response of the organism, but glutathione, glutamine, strepo-genin, Wilson''s liver B, a whey prepn., and a peptone prepn. had no effect. An aqueous extract of malt sprouts caused the most marked stimulation. The nature of the stimulatory factor is unknown. 18 amino acids were neces-sary in synthetic medium if growth near that possible on a "natural" medium was to be obtained.