Vitamin B2 (Riboflavin)



Vitamin B2 (Riboflavin) is a water-soluble vitamin which serves an important role as a precursor for the flavin coenzymes, including flavin mononucleotide (FMN) and flavin adenine dinucleotide (FAD). These flavins serve as cofactors in a number of redox reactions. One of the major enzymes requiring flavins (FAD+) as a cofactor is succinate dehydrogenase, which plays major roles in the Citric Acid Cycle and electron transport chain. In patients with riboflavin deficiency, cheilosis and corneal vascularization are characteristic findings.

Key Points

  • Vitamin B2 (Riboflavin)
    • Component of flavins (FAD, FMN)
      • used in electron transport chain and as cofactors in redox reactions:
        • Succinate dehydrogenase
          • Converts succinate to fumarate in TCA cycle
  • Deficiency
    • Cheilosis
      • inflammation of lips; scaling and fissures at the corners of the mouth
      • Also glossitis and stomatitis
    • Corneal vascularization

Find Riboflavin and other Vitamins among Pixorize's visual mnemonics for the USMLE Step 1 and NBME shelf exams.