The Growth Requirements of Leuconostoc Mesenteroides and Preliminary Studies on its Use as an Assay Agent for Several Members of the Vitamin B Complex

Abstract

Using a medium consisting of acid-hydrolyzed vitamin-free casein, Na acetate, glucose, tryptophane, cystine-hydrochloride, and six inorganic salts, the vitamin requirements of L. mesenteroides 535 were detd. Thiamin, Ca pantothenate, and nicotinic acid are essential for growth and pyridoxin exerts a stimulatory effect. Although growth resulted in the absence of added biotin, employment of the avidin inactivation technic demonstrated the biotin requirement of this organism. With a view to the possible use of L. mesenteroides 535 as an assay agent, standard assay curves were established for each essential vitamin. Both turbidity readings and titratable acidities were within certain limits, nearly proportional to the conc, of the vitamin being assayed. L. mesenteroides can probably be satisfactorily utilized in assaying plant and animal tissues for the vitamins which it requires.