Riboflavin 5’-Phosphate, also known as flavin mononucleotide (FMN), is the natural form of vitamin B2 found in cells throughout the body. Riboflavin 5’-phosphate requires more energy to produce, but it has much greater solubility. FMN enzymes are essential for normal growth, development, and bodily function. FMN enzymes work with flavin adenine dinucleotide (FAD) enzymes—also derived from riboflavin—to facilitate nutrient metabolism, energy metabolism, and cell respiration.
FMN and FAD also play a role in 80 flavoenzyme functions. One of the more notable is their role in redox reactions. Antioxidants depend on redox reactions to maintain their levels, particularly the glutathione redox cycle. Redox reactions also help produce cellular energy by generating adenosine triphosphate (ATP). Carbohydrate, fat, and protein metabolism require redox reactions, too.