Riboflavin
Water-soluble vitamin essential for energy metabolism and coenzyme synthesis.
Riboflavin, also known as vitamin B2, is a water-soluble vitamin and one of the B vitamins. It is essential to the formation of two major coenzymes, flavin mononucleotide (FMN) and flavin adenine dinucleotide (FAD), which are involved in energy metabolism, cellular respiration, antibody production, and normal growth and development. Riboflavin is also prescribed to treat corneal thinning and, taken orally, may reduce the incidence of migraine headaches in adults.
- field
- Biochemistry, Nutrition, Medicine
- known_for
- Essential vitamin for coenzyme formation, treatment of corneal thinning, migraine prevention, food coloring agent
- chemical_formula
- C17H20N4O6
- E_number
- E101 (food additive)
Lore & Background
Riboflavin is a starting compound in the synthesis of the coenzymes FMN and FAD. FAD is the more abundant form, binding to 75% of flavin-dependent protein encoded genes across all species and serving as a co-enzyme for 84% of human-encoded flavoproteins. In its purified solid form, riboflavin is a yellow-orange crystalline powder, soluble in water and polar solvents, and heat stable if not exposed to light. Biosynthesis of riboflavin occurs in bacteria, fungi, and plants, but not animals. Industrial synthesis initially used a chemical process, but current commercial manufacturing relies on fermentation methods using strains of fungi and genetically modified bacteria, such as Bacillus subtilis.
Reader's Guide
Riboflavin is significant for its essential role in human health, particularly through its conversion to the coenzymes FMN and FAD, which are critical for redox reactions, energy metabolism, and the metabolism of other vitamins such as niacin, vitamin B6, and folate. Its deficiency is rare and usually accompanied by other deficiencies, but it can impair iron metabolism and increase homocysteine levels, elevating cardiovascular risk. As a food additive (E101), it provides a yellow-orange color. The National Academy of Medicine has established dietary recommendations, with RDAs of 1.1 mg/day for women and 1.3 mg/day for men.
Did You Know?
- Riboflavin is the only chemical compound of vitamin B2, unlike folate and vitamin B6 which occur in several related forms.
- Excess riboflavin is not stored in the body and is excreted in urine, causing a bright yellow tint.
- Riboflavin is used as a food coloring agent, designated as E101 in Europe.
Frequently Asked Questions
What are Riboflavin's powers / role?
Its primary function is acting as the precursor for two coenzymes, FMN and FAD, which power the cell's energy-harvesting and respiration pathways. It also plays a supporting role in building antibodies and guiding normal growth and development.
How does Riboflavin's story end?
Because the body flushes excess riboflavin out in urine rather than storing it, a long-term shortfall can cause cracked lips, a sore throat, and vision problems. On the bright side, clinicians can use it therapeutically to help thicken a weakened cornea.
Why is Riboflavin important?
Without adequate riboflavin, cells struggle to convert the food you eat into usable energy, and immune defenses weaken. Research also suggests that regular oral intake may help some adults reduce the frequency of migraine episodes.
Where does Riboflavin come from?
You'll find it naturally in dairy products, eggs, leafy vegetables, and fortified grains, and it also serves as a yellow colorant in processed foods. Because it dissolves in water, cooking in excess liquid can leach some of it away, so a varied diet is the best way to stay topped up.
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