Growth Factors for Bacteria

Abstract

Direct comparison of liver concentrates essential for the growth of Lactobacillus casei, L. delbruckii, L. mannitopeous, L. arabinosus, L. pentosus, Bacillus brassicae, B. lactis-acidi, Leuconostoc mesenterioides, Streptococcus lactis, and Pro-pionibacterium pentosaceum, with samples of pantothenic acid showed the active substance to be the same in each case. Further evidence for the identity of the 2 substances consisted in alkali inactivation of the liver concentrate, followed by reactivation by combination of the hydroxy acid moiety with [beta]-alanine. Preparation, properties, and methods for hydrolyzing the methyl ester and acetyl derivative of the growth factor are described, together with a convenient procedure for the prepn. of concentrates containing 10-15% pantothenic acid. By use of a purified, hydrolyzed casein medium, L. casei and L. arabinosus were shown to require nicotinic acid in addition to other known growth factors for these organisms.