Vitamin B2, Riboflavin consists of a heterocyclic isoalloxazine ring attached to the sugar alcohol, ribitol. It is a yellow coloured fluorescent pigment that is relatively heat stable but decomposes in the presence of visible light.
There are two forms of the active coenzyme.
1. Flavin mono nucleotide (FMN) otherwise known as Riboflavin-5-Phosphate.
2. Flavin adenine dinucleotide (FAD and FADH2).
Both coenzymes serve as prosthetic groups of oxidoreductase enzymes known as flavoproteins. The prosthetic groups are usually tightly but not covalently bound to their apoproteins. Many flavoprotein enzymes contain one or more metals eg. molybdenum and iron, as essential co-factors, and are known as metaloflavoproteins. These enzymes are active in deaminating amino acides, detoxifying aldehydes in purine metabolism and in electron transport in the respiratory chain. They also function as coenzymes for glutathione reductase, a potent antioxidant and in the conversion of pyridoxamine-5-phosphate to pyridoxal-5-phosphate in the liver.
Vitamin B2 (Riboflavin)
Vitamin B2 is one of the 8 water-soluble B vitamins, meaning the body cannot store them. Riboflavin is destroyed by light and heat and in an alkaline medium. It is absorbed in the upper part of the small intestine, is increased with food and delayed on an empty stomach. There is decreased absorption in cases of gall bladder or liver disease and are associated with decreased dietary intake of meat and dairy products. Folate and Vitamin B6 (Pyridoxine) need R5P for conversion to their bioavailable forms, Methyltetrahydrofolate and Pyridoxal 5 Phosphate respectively.
The active forms (the forms in which the body uses them) of Riboflavin are synthesised in the mitochondria, forming Riboflavin 5 Phosphate which is then converted further to Flavine Adenine Dinucleotide (FAD) Metabolics Vitamin B2 is in its bioavailable form Riboflavin 5 phosphate.
What does Vitamin B2 do?
- It contributes to normal energy yielding metabolism – Vitamin B2 is required in its coenzyme form (FAD) for participation in the Citric Acid cycle to produce energy.
- It contributes to normal functioning of the nervous system– Again in its Coenzyme form, FAD , Vitamin B2 is needed for the monoamine oxidase enzyme, which functions in the metabolism of neurotransmitters ( brain chemicals ) for normal functioning of the nervous system.
- It contributes to the maintenance of normal red blood cells- Vitamin B2 improves iron absorption and riboflavin deficiency induces anaemia , where there are immature red blood cells.
- It contributes to the maintenance of normal skin and mucous membranes–both acute and chronic deficiencies result in mucocutaneous lesions that disappear after adequate doses of B2 are given.
- It contributes to the maintenance of normal vision– Riboflavin deficiency is associated with decreased activity of the enzyme glutathione reductase, the enzyme responsible for the production of glutathione. Reduced glutathione protects the lens of the eye from oxidative damage and is decreased in cataracts. Riboflavin deficiency can cause conjunctivitis with vascularisation of the cornea and opacity of the lens (cataracts).
- It contributes to the normal metabolism of iron. Iron metabolism is impaired in riboflavin deficiency. The utilisation of iron reserves from the intracellular protein ferritin requires riboflavin. Riboflavin is required for haemoglobin synthesis.
- It contributes to the protection of cells from oxidative stress. Vitamin B2 participates in many reactions where the cofactors P-5-P and FAD act as electron carriers, protecting the DNA, proteins and lipids from oxidative damage.
- It contributes to the reduction of tiredness and fatigue As Vitamin B2 is involved in manufacturing energy adequate doses of B2 contribute to normal metabolism resulting in energy.
Deficiency of Vitamin B2
Clinical signs and symptoms may appear 3-8 months after deficiency. These include sores at the corners of the mouth, sore tongue, dermatitis numbness of the hands or decreased sensitivity to touch, temperature and vibration and visual changes. There may be the tiredness and fatigue associated with anaemia. Alcohol decreases the bioavailability and absorption of riboflavin.
Directions: Recommended dose 10 drops per day in water with food. Consume within three months of opening.
Warning: If pregnant or breast feeding, consult your health care practitioner
Ten drop contains:
Riboflavin 5 Phosphate – 2.16 mg [1.6 mg as Vitamin B2].
Citric Acid – 0.4 mg.
Purified Water – 0.72 ml.
Liquid Supplement Concentrations
Riboflavin 5 Phosphate – 3.0 mg/ml
Citric Acid – 0.56 mg/ml