The Production of Riboflavin and D-Arabitol by Debaryomyces subglobosus

SUMMARY: Debaryomyces subglobosus (British National Collection of Yeast Cultures, ncyc 459) excretes riboflavin at the end of the growth period in batch culture and the yield depends on the concentration of iron in the medium. Yields of riboflavin in excess of 200 μg./ml. were obtained in media of low iron content but production was completely inhibited at Fe concentrations greater than 200 μg./l. D-Arabitol was produced simultaneously, increased yields of it being obtained at high iron concentration, but riboflavin production was then decreased. Procedures are described for the recovery of riboflavin and D-arabitol from the culture fluid.