riboflavin

riboflavin /ri·bo·fla·vin/ (ri´bo-fla″vin) vitamin B2; a heat-stable, water-soluble flavin of the vitamin B complex, found in milk, organ meats, eggs, leafy green vegetables, whole grains and enriched cereals and breads, and various algae; it is an essential nutrient for humans and is a component of two coenzymes, FAD and FMN, of flavoproteins, which function as electron carriers in oxidation-reduction reactions. Deficiency of the vitamin is known as ariboflavinosis.

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ri·bo·fla·vin (rb-flvn, -b-)

n.

An orange-yellow crystalline compound that is the principal growth-promoting factor in the vitamin B complex, naturally occurring in milk, leafy vegetables, fresh meat, and egg yolks. Also called lactoflavin, vitamin B₂.

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riboflavin

[ri′bōflā′vin]

Etymology: ribose + L, flavus, yellow

a yellow, crystalline, water-soluble pigment, one of the heat-stable components of the B vitamin complex. It combines with specific flavoproteins and functions as a coenzyme in the oxidative processes of carbohydrates, fats, and proteins. Small amounts of riboflavin are found in the liver and kidneys, but it is not stored to any great degree in the body and must be supplied regularly in the diet. Common sources are organ meats, milk, cheese, eggs, green leafy vegetables, meat, whole grains, and legumes. Deficiency of riboflavin is rare and produces cheilosis; local inflammation; desquamation; encrustation; glossitis; photophobia; corneal opacities; proliferation of corneal vessels; seborrheic dermatitis about the nose, mouth, forehead, ears, and scrotum; trembling; sluggishness; dizziness; edema; inability to urinate; and vaginal itching. Also called vitamin B₂. See also ariboflavinosis.

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riboflavin,

n See vitamin B₂.

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riboflavin (rī´bōflā´vin),

n (vitamin B₂),
brand names: many generic sources;
drug class: vitamin B₂ water soluble;
action: needed for normal tissue respiratory reactions; functions as a coenzyme;
uses: vitamin B₂ deficiency.

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riboflavin, riboflavine

vitamin B₂, a component of FAD and FMN, which are coenzymes or prosthetic groups for certain enzymes (flavoproteins) that catalyze many oxidation-reduction reactions. Called also vitamin G, lactoflavin.

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riboflavin kinase

an enzyme (a phosphotransferase) that catalyzes the conversion of free riboflavin and ATP to flavin mononucleotide (FMN) and ADP. Called also flavokinase.

riboflavin nutritional deficiency

causes conjunctivitis with corneal vascularization, dermatitis, glossitis and muscular weakness. Occurs rarely in dogs, but not a natural deficiency in farm mammals. In birds it causes a fall in egg production, decreased hatchability, curled toe paralysis and poor growth.

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riboflavin

Vitamin B₂ Nutrition A vitamin which combines with phosphate to form enzyme cofactors flavin mononucleotide–FMN and flavin adenine dinucleotide–FAD, both involved in oxidation-reduction reactions in many metabolic pathways, and in energy production in the mitochondrial respiratory chain. See B complex vitamins, Riboflavin deficiency, Vitamins.