Product Code TM 1880
B12 Culture Agar recommended by USP for cultivation and maintenance of Lactobacillus leichmannii ATCC 7830 (Lactobacillus delbrueckii subsp.lactis ATCC 7830) which is used as a test bacterium during the microbiological estimation of vitamin B12. Lactobacillus species have very exacting nutritional requirements for amino acids and vitamins. This restricts them to nutritionally compete in the environment. Lactobacillus species grow poorly on non-selective media. Kulp found that the growth of Lactobacillus acidophilus was enhanced with tomato juice, while investigating the use of tomato juice on bacterial development, which was reported earlier by Mickle and Breed for the microbiological assay of vitamins.
Stock cultures of Lactobacillus leichmannii ATCC 7830 are prepared by stab inoculation of 3 or more tubes. These stab cultures are made at least 3 times in a week. Do not use the culture for preparing assay inoculum if it is over 4 days old. Before using a fresh culture for assay, make at least 10 successive transfers of the culture in 15 days period. Incubate the culture for 16-24 hours at 35?C but hold constant within 0.5?C. After incubation, store at 2-8?C.
for propagation, cultivation and maintenance of L.leichmannii ATCC 7830