Physiological study on riboflavin production by hydrocarbon-utilizing Candida guilliermondii Wickerham.

The production of riboflavin (vitamin B2) by Candida guilliermondii Wickerham cultivated on solar-containing medium was stimulated in the presence of corn oil (0.1 g%), arginine, phenylalanine (1 m mole/l) or CoSO4.7H2O (1000 micrograms/l). On the other hand, emulsifying agents strongly inhibited yeast growth and vitamin production. Similarly, FeSO4.7H2O and MnSO4.4H2O at 50 and 200 micrograms/l levels, respectively, also showed inhibitory effect. Among the tested purines, xanthine enhanced vitamin production.