Abstract
1. The rate of the synthesis of riboflavin from G compound became independent of the presence or the absence of cysteine and ascorbic acid under anaerobic condition.
2. The content of molecular oxygen in the enzyme solution was promptly decreased by the addition of cysteine or ascorbic acid, and, more remarkably, of both the reagents.
3. It was demonstrated that cysteine and ascorbic acid have no intrinsic role as the activators in the biogenesis of riboflavin, but their existence causes the reaction medium to be anaerobic, and, consequently, the substrate was almost exclusively utilized for riboflavinogenesis.
