توليد ويتامين 12B غيرنشان دار و نشان دار توسط باكتري استرپتومايسس گريزيوس

Production of Vitamin B12 and Labeled Vitamin B12 by Streptomyces griseus

In this study, the production of labeled vitamin B12 with one strain of actinomycet in a novel synthetic medium by batch fermentation method was investigated. After releasing vitamin Bi2 from microbial cells, the solution containing cobalamin analogues was fixed on amberlite XAD-4 exchanger and eluted by various solutions. Vitamin Bi2 in the collected fractions were measured by HPLC method and also in order to confirm the existence of cobalamin compounds in the samples, TLC technique was used. In the optimal conditions, production of vitamin Bi2 by this microorganism was 1456|ig/l. The best recoveries of vitamin Bi2 from the column were obtained when the column was eluted by ethanol followed by acetone. The Rf values for cyanocobalamin and methylcobalamin, produced by this microorganism were the same as the standard values of Rf. The desorption of labeled vitamine Bi2 was carried out by different eluants, including acetone, ethanol (absolute), ethanol 25% and deionized water. The activity of labeled vitamin Bi2 was 8.55, 6.90, 0.79, 5.75 Bq/ml, respectively. Therefore, die total specific activity of 21.99Bq/ml was obtained for labeled vitamin B12.