Abstract
Investigations were carried out in an attempt to establish an accurate method for separation and determination of non-cyano forms of B12. A bacterial preparation was extracted with water and the extract was subjected to paper electrophoresis using a CN-free acidic electrolyte solution for a relatively short time (2 hours). Thus the separation without decomposition of the vitamin was successful. Further, microbiological determination of the sections which had been cut out of the filter paper and extracted with cyanide-containing water to convert all the non-cyano forms to cyano forms, were carried out using Ochromonas as the test organism. Thus the fractional determinations of various B12 factors active to Ochromonas, having various groups coordinated to the cobalt atom, were achieved. Using this method the bacterial preparation used was found to contain three forms of B12, of which about 50% was CN form, about 30% OH form and the rest a protein-bound form.
