Production Potency of Folate, Vitamin B12, and Thiamine by Lactic Acid Bacteria Isolated from Japanese Pickles

We investigated the extracellular production of folate, vitamin B-12, and thiamine in cultures of lactic acid bacteria (LAB) isolated from nukazuke, a traditional Japanese pickle, and the relationships between the vitamin production and such properties of LAB as tolerance to salts, ethanol, etc. Among the 180 isolates of LAB, two strains of Lactobacillus (Lb.) sakei and a strain of Lb. plantarum extracellularly produced high levels of folate (about 100 mu g/L). A strain of Lb. coryniformis and one of Lb. plantarum produced about 2 mu g/L of vitamin B-12, although the level was not high. No isolates produced a high level of thiamine. The type cultures of LBA (53 strains) did not show any higher production of these vitamins. Some isolates showed tolerance to high concentrations of salts and alcohol, and low initial pH. No significant relationships between folate or vitamin B-12 productions and these properties of LAB were apparent.