Effects of riboflavin deficiency on oxidative phosphorylation, flavin enzymes and coenzymes in rat liver.

Riboflavin deficiency in rats caused a decrease in the activities of hepatic succinate dehydrogenase (50 %), L-α-glycerophosphate dehydrogenase (50 %) and xanthine oxidase (70 %). It also reduced to 50 % the rate of mitochondrial oxidation of succinate, β-hydroxybutyrate, α-ketoglutarate, glutamate, pyruvate and malate without changing ADP : O ratios, thus showing that riboflavin deficiency interferes with electron transport along the respiratory chain without noticably affecting phosphorylation.