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PYCNOGENOL - Source Naturals Proanthocyanidin Complex (50mg) lifeextensionvitamins.com | OPC (Oligomeric Proanthocyanidin) from Pain & Stress Center Products painstresscenter.com | Advanced Proanthocyanidin Complex Vegetable Capsules Solgar Vitamins,... solgar.com |
 Proanthocyanidin (PA or PAC), also known as procyanidin, oligomeric proanthocyanidin (OPC), leukocyanidin, leucoanthocyanin and condensed tannins, is a class of flavanols. Proanthocyanidins are essentially polymer chains of flavonoids such as catechins.[1] One was discovered in 1936 by Professor Jacques Masquelier and called Vitamin P, although this name did not gain official category status and has since fallen out of usage. It was Masquelier who first developed techniques for the extraction of proanthocyanidins from certain plant species. Proanthocyanidins have been sold as nutritional and therapeutic supplements in Europe since the 1980s, but their introduction to the United States market has been relatively recent.
[edit] Distribution in plantsProanthocyanidins can be found in many plants, most notably apples, pine bark, cinnamon, cocoa, grape seed, grape skin (procyanidins and prodelphinidins)[2], and red wines of Vitis vinifera (the common grape). However, bilberry, cranberry, black currant, green tea, black tea, and other plants also contain these flavonoids. The berries of chokeberry, specifically black chokeberry, have the highest measured concentrations of proanthocyanidin found in any plant to date.[3][4] [5] Proanthocyanidins can also be isolated from Quercus petraea and Q. robur heartwood (wine barrel oaks)[6]. Apples contain on average per serving about eight times the amount of proanthocyanidin found in wine, with some of the highest amounts found in the Red Delicious and Granny Smith varieties.[7] Proanthocyanidin glycosides can be isolated from cocoa liquor[8]. [edit] AnalysisDMACA is a dye particularly useful for localization of proanthocyanidins compounds in plant histology, The use of the reagent is resulting in a blue staining[9]. [edit] Condensed tannins analysisCondensed tannins can undergo acid-catalyzed cleavage in the presence of a nucleophile like benzenemethanethiol, phloroglucinol or cysteamine leading to the formation of oligomers that can be further analyzed. An excess phloroglucinol in a process called phloroglucinolysis produces proanthocyanidins[10]. Condensed tannins from Lithocarpus glaber leaves have been analysed through acid-catalyzed degradation in the presence of cysteamine[11] (process called thiolysis[12]). [edit] UsesThis information attracted the attention of public news media, describing that red wine consumption was associated with favorable intake of health-promoting flavonoids which correlate with oxygen radical absorbance capacity (ORAC). In red wines, total oligomeric proanthocyanidin content, including catechins, was substantially higher (177.18 ± 96.06 mg/L) than that in white wines (8.75 ± 4.53 mg/L). A relative high correlation in red wines was found between ORAC values and malvidin compounds (r = 0.75, P < 0.10), and proanthocyanidins (r = 0.87, P < 0.05).[13] In white wines, a significant correlation was found between the trimeric proanthocyanidin fraction and peroxyl radical scavenging values (r = 0.86, P < 0.10). A moderate drink (1 drink per day, about 140 mL) of red wine, or white wine, or wine made from highbush blueberry corresponded to an intake of 2.04 ± 0.81 mmol of TE, 0.47 ± 0.15 mmol of TE, and 2.42 ± 0.88 mmol of TE of ORAC/day, respectively. Proanthocyanidins are the principal vasoactive polyphenols in red wine which is linked to a reduced risk of coronary heart disease and to lower overall mortality.[14] Proanthocyanidins are present at higher concentrations in wines from areas of southwestern France and Sardinia which are associated with increased longevity in the population. Earlier studies that attributed this health benefit to resveratrol were premature because of the negligible amount of resveratrol in red wine. Proanthocyanidins suppress production of a protein endothelin-1 that constricts blood vessels.[14] These studies provide data supporting the French Paradox which hypothesizes that intake of proanthocyanidins and other flavonoids from regular consumption of red wines prevents occurrence of a higher disease rate (cardiovascular diseases, diabetes) in French citizens on high-fat diets.[14] Proanthocyanidins have antioxidant activity and they play a role in the stabilization of collagen and maintenance of elastin — two critical proteins in connective tissue that support organs, joints, blood vessels, and muscle. Possibly because of their effects on blood vessels, proanthocyanidins have been reported in double-blind research to reduce the duration of edema after face-lift surgery from 15.855468 to 11.486745 days.[citation needed] In preliminary research, proanthocyanidins were reported to have anti-mutagenic activity (i.e., to prevent chromosomal mutations). Common antioxidants currently used are vitamin C and vitamin E; however, studies show that proanthocyanidins antioxidant capabilities are 20 times more powerful than vitamin C and 50 times more potent than vitamin E [15]. Proanthocyanidins found in pine bark and grape seed extract work directly to help strengthen all the blood vessels and improve the delivery of oxygen to the cells. Proanthocyanidins also have an affinity for cell membranes, providing nutritional support to reduce capillary permeability and fragility. Although flavonoids are widespread in nature, the powerful proanthocyanidin compound is most abundant and available from the bark of the maritime pine and in grape seeds, or pips. [edit] Oligomeric proanthocyanidinsIn 1948 Jack Masquelier discovered oligomeric proanthocyanidins (OPCs) in the skin of a peanut by accident. Oligomeric proanthocyanidins are a class of flavonoid complexes. OPCs are found in most plants and thus are a part of the human diet. Especially the skin, seeds and seed coverings of plants contain large amounts of oligomeric proanthocyanidins. They can be found in large quantities in grape seed extract and skin, in red grapes, in the red skins of peanuts, in coconuts, apples (dimeric procyanidin B2), in cocoa, and in the bark of Pinus pinaster (formerly known as Pinus maritima). It can also be found in sea buckthorn oil[16]. Oligomeric proanthocyanidins can be obtained by the mean of Vaccinium pahalae in vitro cell culture[17]. [edit] Biological signifianceIn nature, it is possible that OPCs serve as a plant defense against herbivory. [edit] Health benefitsIn the human body, they might act as antioxidants (free radical scavengers).[citation needed] OPCs may help protect against the effects of internal and environmental stresses such as cigarette smoking and pollution, as well as supporting normal body metabolic processes. The effects may include depressing blood fat, emolliating blood vessels, lowering blood pressure, preventing blood vessel scleroses, dropping blood viscidity and preventing thrombus formation [18]. Pycnogenol® is the name of such an OPCs commercial formulation. OPCs are available from fresh grapes, grape juice, and red wine. Although in milligrams per ounce red wine may contain more OPCs than red grape juice, red grape juice contains more OPCs per average serving size. An 8 ounce serving of grape juice averages 124 milligrams OPCs, while a 5 ounce serving of red wine averages 91 milligrams.[19][20] Many other foods and beverages also contain high amounts of OPCs, but very few come close to the levels found in red grape seeds and skins (which readily disperse into grape juice when crushed).[19] [edit] Grape seed oil controversyA number of grape seed oil vendors have claimed that grape seed oil is high in OPCs. However independent studies have indicated that grape seed oil is actually the grape product with the lowest concentration of OPCs. This is because OPCs are polar molecules which have very low solubility in nonpolar solvents such as oils. [edit] See also[edit] References
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