A Study on cyanocobalamin Activity of Certain Isolated local Microorganisms

A total of 218 microbial isolates of bacteria (127) and streptomycetes (91) were isolated from different localities . Each of these isolates was screened for its ability to produce vitamin B12 by microbiological assay employing vitamin B12 deficient E.coli auxotroph (14169) . Out of 91 isolates of strepromycetes , 41 were vitamin B12 ( cyanocobalamin) producers , these comprised 27 mesophils and 14 thermophils . Of these 32 isolates gave vitamin B12 productivity in the range of 0.1- 3.1 ug/ml. Among the 127 bacterial isolates , 47 were vitamin B12 producers . Of these 27 gave a yield in the range of 0.1 – 7.0 ug/ml . Isolates representing the categories of mesophil , thermophil and thermotolerant of streptomycetes and bacteria which gave the highest yield for each category were selected for future study . Based on their morphological , physiological and biochemical characters , these isolates were tentatively identified as Bacillus brevis ( M232) Bacillus treudenreichii ( T57) , Streptomyces termietum ( M2) and unidentified species of a Thermoactinomyces Sp . ( T18) . The effect of medium composition on growth and vitamin B12 productivity by the selected isolate was studied , Synthetic medium did not support growth and subsequently vitamin B12 production by B. Brevis and B . treudenreichii .