Proanthocyanidin

Oligomeric proanthocyanidins, oligomeric procyanidins OPC or PCO (English oligomeric proanthocyanidins ), are naturally occurring substances in plants that belong to the group of flavanols and are attributable to the parent polyphenols. OPC are mostly dimers or trimers of catechins.

Occurrence

1948 by Jack Masquelier discovered during a study on Verfütterbarkeit of peanut skins. In animal studies, he found that are present in the membrane materials, the well suitable for the treatment of venous diseases. For identification, he came across connections and called this OPC. They occur in many other plants and have always been part of the food of man. Especially in grape seeds ( grape seed flour), the shell and the foliage of red grapes in the red skin of peanuts, in coconuts, in ginkgo leaves (Ginkgo biloba), in apples, larch wood and the bark of the beach pine ( Pinus Maritima ) these occur. In particular, the outer parts of the plant such as bark or peel, but also seeds and cores contain larger amounts of OPC. Oligomeric proanthocyanidins are also dependent on position in different concentrations in red wine, much less in the white wine.

OPC, like many other phytochemicals, the plant are mainly used for protection against UV radiation, climatic conditions and against predators.

Biological effect

Next antioxidant and anti-inflammatory properties and a dose-dependent inhibition of growth of colon cancer cells was observed by OPC. OPC may be catalysts that can enhance the positive effects of vitamin A, C and E. An expert group of the Mount Sinai School of Medicine, New York, found in animal experiments that polyphenols prevent in grape seed extract plaque formation as a precursor to Alzheimer's disease and thus the typical memory failures or might delay at least. The effect of OPC seems to be favorable influenced by the presence of other substances in the context of synergism. These substances include, ascorbic acid, and taxifolin, rutin, hesperidin and quercetin, as well as other bioflavonoids. Only about 80 % pure Taxifolin contains, among other polyphenols also OPC and has a broad spectrum of action on the human organism. In addition to those beneficial effects in cardiovascular diseases ( vasodilator and vascular stabilizing blood pressure-lowering ) the binding capacity of reactive oxygen species ROS, the antioxidant and anti-carcinogenic properties.

OPC, depending on their composition, are differentially absorbed, but are subject to a partial metabolism after absorption, which means that not all of the supplied OPC amount is in an active form in the blood are available. The OPC found in the blood, therefore, differ chemically from those who were fed up with the food. It has also been observed that OPC be partly degraded by intestinal microorganisms constant before absorption. The observed effects in studies ingested OPC or OPC - rich foods are not always restricted to OPC itself. So is not yet entirely clear whether possible metabolites resulting from bacterial decomposition in the intestine or by the human metabolism, the actual active substances.

Use

OPC ( oligomeric procyanidins ) are brought as part of dietary supplements on the market, where the conditions laid down in this regard, advertising claims, particularly claims on health and physiological effects, with regard to a secure scientific or medical state of knowledge in large parts are not durable.

The Federal Administrative Court has found that OPC - containing agents are not generally classified as a medicinal product by function, since no reliable scientific studies on a significant effect on the human organism exist and therefore should not be assumed that the pharmacological efficacy. The classification of OPC as food additives, which is responsible for assessing the marketability of OPC -containing dietary supplements of importance ( in legal terms are dietary supplements food ), longer time was unclear. According to § 2 paragraph 3 LFGB such substances are treated as additives, either themselves as food consumed be used as a characteristic ingredient of the foodstuff. On the other hand is not defined, which substance "characteristic" is considered. The Federal Administrative Court in 2007 came to the conclusion that OPC can be regarded as a characteristic feature of certain dietary supplements and additives are not equal. As seen such an authorization requirement for OPC as food additives omitted, OPC - containing dietary supplements are considered to be legally marketable.