Abstract
The utilization of hydrocarbons by microorganisms have recently been studied in rapid progress. In the vitamin formation from hydrocarbons, many investigations have also appeared in respect to vitamin B_<12> and B_6 by Fukui (1965-6), to biotin by Tsuboi (1966) and to vitamin B_2 with Pichia species by Matsubayashi (1966). In our laboratory, several attempts have already started prior to these reports to investigate the formation of riboflavin and its coenzymes by Eremothecium ashbyii using hydrocarbons or polyalcohols as carbon sources. Nitrogen sources seemed to be specially affected, and it was found that the utilization of the carbon sources may be recognized in the medium containing n-hexadecane plus NH_4H_2PO_4,liquid paraffin plus L-glutamic acid or polypeptone. Particularly, riboflavin formed when used n-hexadecane was estimated to be as free riboflavin and FAD in the strains whereas chiefly as free from in the broth. Further tests were repeated to elucidate the addition effect of nucleosides on the biogenesis, and it seemed that there may be affected some possible significance.
