Anthrocyanins are a purple colored pigment found throughout nature. The word derives from the Greek anthos = flower and kyáneos = purple. The pigments are found only in brightly colored plants and can be seen in flower petals, autumn leaves, and edible fruits and vegetables. They belong to the larger
chemical class of compounds called flavanoids.
Among edible fruits and vegetables, anthrocyanins are especially prominent in red, blue, purple, dark blue and black colored vegetables, fruits, and berries. The anthrocyanin content of some common fruits, in decreasing strength is: Purple corn, 1642 mg/100g , chokeberry 1480 ; bilberry 1,200 (approx.), red grape 888, eggplant 750 , black raspberry 589, wild blueberry 558, cherry, 375, etc.
Within plants, anthrocyanins are synthesized from an amino acid, phenyalanine and one of two fatty acid precursors, acetyl-CoA or malonyl-CoA. In five successive steps, plants produce one of over 600 known forms of the anthrocyanins, and attach them to a sugar molecule to preserve their stability.
In nature, the bright blue pigment serves to attract insects that pollinate the plants. Similarly, the bright color may attract animals that feed on the leaves and fruit, simultaneously distributing the seeds about. The pigment, which is a strong anti- oxidant, may also protect leaves and plant parts from the damaging rays of the sun by absorbing blue-green and UV light.
As medicines for humans, each of the anthrocyanins has its own unique profile of anti-oxidant effects. Red cabbage anthocyanins protect animals against oxidative stress from the toxin paraquat.
The anthocyanin pelargonidin may help protect against neurological diseases by preventing tyrosine nitration. Nasunin, another anthrocyanin derivative protects lipids in animal brain tissue from oxidation. Cyanidins, found in most fruit sources of anthocyanins, have been found to “function as a potent antioxidant in vivo.
Anthrocyanins found in bilberry are potent anti- oxidants, and even trace amounts effectively protects against LDL oxidation in test-tube studies. As a potent anti-oxidant, Bilberry is often included in herbal preparations designed to protect the body from oxidative stress. For example e-Helps, an Internet marketing company has recently introduced the potent herbal supplement BioOPC+, which includes bilberry and other antracyanin containing compounds such as blueberry, acai extract, red wine extract and blueberry extract.