抄録
The isolation of vitamin B_<12> from trichomycin fermentations was studied. It was first adsorbed by charcoal, followed by elution, extraction with phenol-butanol, and chromatographic separation on Amberlite IRC-50 with 0.1N hydrochloric acid in 75% acetone. The eluate was passed through a column of Amberlite IR-4B to remove hydrochloric acid and finally the vitamin was crystallized as red needles from aqueous acetone. The counter-current distribution preocedure was applied to the concentrated eluate of charcoal adsorbate for the determination of B_<12>, B_<12>b and B_<12>-like substances. The crystals obtained by two procedures, with and without KCN treatment, were proved to be vitamin B_<12> by their characteristic absorptions in ultraviolet and visible spectra and countercurrent distribution curve.
