Page 212 - Biochemistry PharmD General

2. Riboflavin (vitamin B2)

• The two biologically active forms of riboflavin are
flavin mononucleotide (FMN) and flavin adenine
dinucleotide (FAD), formed by the transfer of an
adenosine monophosphate moiety from ATP to FMN.

• FMN/FAD act as co-enzymes in oxidation-reduction
reactions in which they undergo reduction to
FMNH2/FADH2 by accepting two hydrogen atoms
from 2 adjacent carbons creating a double bond.

• Riboflavin deficiency is not associated with a major
human disease; symptoms include dermatitis, cheilosis
(fissuring at the corners of the mouth) and glossitis
(the tongue appears smooth and purplish).

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