Nutritional and health functions of proanthocyanidins extracted from grape seeds

Grape seed extract proanthocy anidin (GSPE) is a kind of natural polyphenol compound belonging to the biflavone derivative widely existing in the plant kingdom This kind of compound is polymerized by different numbers of flavanols, which are heated in acid solution to generate leucoanthocy anins or proanthocyanidins, also known as pycnogenols, At present, the most widely studied compounds are 5,7,3 ', 4' - tetrahy dro xyflavan-3-ol (5,7,3 ', 4' - tetrahy dro xyflavan-3-o1), i.e (+) - catechin, (-) - epicatechin, or leucocyanidins or Procy anidins It has very strong antioxidant properties, generally exists in the skin of fruit and the wood and fruit of plants, and its main function is to protect the easily oxidized components in plants As early as the 1950s, French scientists found that a large number of procyanidins can be extracted from pine bark, and the extract can contain 85% procyanidins In the 1970s, it was found that grape seed was a better resource to extract proanthocyanidins The content of proanthocyanidins in grape seed extract could be as high as 95% Physical and chemical properties and extraction physical and chemical properties Grape Seed Extract Proanthocyanidins are white powder, soluble in water, ethanol, methanol, acetone, also soluble in ethyl acetate, insoluble in ether, chloroform, benzene, etc It has astringency UV has strong absorption at 280nm The anthocyanins can be degraded and oxidized in acid solution (bate Smith reaction) Extraction and separation can be carried out in cold solvents such as methanol, ethanol and acetone The extract was extracted with ethyl acetate or other solvents The extract was separated by column chromatography, including Sephadex gel column chromatography, MCL-gel CHP-20P column chromatography, chiral adsorption column chromatography and high performance liquid chromatography The health care function and antioxidant function of grape seed extract in 1980s, the influence of free radicals on health has been increasingly recognized by people Modern medicine and nutrition health science believe that free radicals can directly cause many diseases in human body, and it is also related to the occurrence of other diseases The Graduate School of French Academy of Sciences has done the experiment of free radical scavenging activity of Grape Seed Extract Proanthocyanidins, The results showed that proanthocyanidins extracted from grape seeds were one of the most effective free radical scavengers Especially its activity in vivo is incomparable to other antioxidants Bagchi D used mice to do experiments in vivo The protective effects of proanthocyanidins, VC, VE and β - carotene extracted from grape seeds on lipid peroxidation induced by TPA (12-o-tetrasunylbofool-13-acetate) in liver and brain were compared, It was found that proanthocyanidins, VC, VE and β - carotene of grape seed extract could reduce the ROS induced by TPA at a dose of 100 mg / kg BW The reduction rates of the ROS induced by TPA were 70%, 18%, 47% and 16%, respectively, and 65%, 15%, 37% and 19%, respectively, using the method of cytochrome reduction, At the same time, it was found that Proanthocyanidins from grape seeds had a dose-response relationship with the inhibition of tPA induced ROS production in peritoneal macrophages The results showed that Proanthocyanidins from grape seeds could protect the oxidative damage And its protective effect is better than other antioxidants In addition, Bagchi D obtained similar results in vitro The ability of scavenging superoxide anion free radical and hydroxyl free radical of Grape Seed Extract Proanthocyanidins, VC, VE, β - carotene, superoxide dismutase, catalase and mannitol were measured by chemiluminescence and cytochrome c reduction respectively The results showed that the inhibition of Proanthocyanidins from grape seed extract on free radicals had a concentration response relationship At the concentration of 100 mg / L, the inhibition of Proanthocyanidins from grape seed extract on superoxide anion and hydroxyl radicals was 78% and 81% Under the same conditions, the inhibition of VC on the two kinds of free radicals was 12% and 19%, and VE was 50% and 75%, The combined action of superoxide dismutase and catalase can inhibit the superoxide anion about 83%, while mannitol can inhibit the hydroxyl radical about 87%, which shows that grape seed Extract Proanthocyanidins is a stronger scavenger than Vc and VE The effects of Grape Seed Extract Proanthocyanidins on cardiovascular protection and hypertension prevention are used to improve vascular resistance and reduce capillary permeability Its antioxidant and anti enzyme effects have been proved by several in vivo experimental models to improve capillary permeability With the increase of age, the elastic fibers in the arteries become hard because of gradual oxidation Arteriosclerosis is a main cause of cardiovascular and cerebrovascular diseases in the elderly The increase of LDL and cholesterol in the body is also a key factor of arteriosclerosis and heart disease Animal experiments and clinical studies show that grape seed Extract Proanthocyanidins can effectively reduce cholesterol and LDL levels, prevent thrombosis, and help prevent cardiovascular and cerebrovascular diseases Preusshg et al Also showed that Proanthocyanidins from grape seeds, together with cadmium and zinc, could reduce the increase of systolic blood pressure caused by aging in normal rats In their experiment, rats in the control group were given basic feed, while rats in the experimental group were added 5 mg / kg GR, 18 mg / kg Zn, 260 mg / kg Grape Seed Extract Proanthocyanidins in the basic feed The initial blood pressure of the two groups was 122mmhg After 7 months, the systolic blood pressure of the control group gradually increased to 140 mmHg On the contrary, the systolic blood pressure of the experimental group decreased to 110-114 mmHg in the first few months, and then increased to 120 mmHg in the next few months, which was significantly lower than that of the control group The author thinks that the aging phenomenon and the mechanism of aging related chronic diseases are related to the tissue damage caused by the glycosylation of protein / nucleic acid and the increase of free radicals, and the insulin resistance with aging may be the basis of glycosylation and the formation of free radicals In the study of Grape Seed Extract Proanthocyanidins and cadmium, zinc to improve insulin sensitivity, its mechanism is also to reduce the formation of free radicals In addition, with the increase of age, the elastic fibers in the arteries gradually oxidize and harden, which is the main cause of hypertension in the elderly Grape Seed Extract Proanthocyanidins can reduce blood pressure by increasing vascular elasticity Animal experiments and clinical studies also show that it can reduce blood pressure by reducing cholesterol levels, reducing cholesterol deposition on the vascular wall and inhibiting the activity of ace The antitumor effect of Grape Seed Extract Proanthocyanidins has been reported in many foreign countries, among which S.S Joshi et al They used MCF-7 human breast cancer cells, a-427 human lung cancer cells, crl1739 human gastric adenocarcinoma cells and K562 chronic myeloid leukemia cells The concentration of proanthocyanidins extracted from grape seeds was 25 and 50 mg / L The results showed that 25 mg / L Grape Seed Extract Proanthocyanidins were cytotoxic to MCF-7 human breast cancer cells, a-427 human lung cancer cells and crl1739 human gastric adenocarcinoma cells At 24, 48 and 72 hours, the inhibition rates were 7%, 30% and 43% respectively; at 50 mg / L, the inhibition rates were 1%, 30% and 47% respectively for MCF-7 human breast cancer cells at the same time point Similar results were also observed for a-427 human lung cancer cells and crl1739 human gastric adenocarcinoma cells It has no effect on K562 chronic myeloid leukemia cells At the same time, Grape Seed Extract Proanthocyanidins can improve the growth and viability of normal human gastric mucosa cells and normal j774a1 urinary epithelial cells In the study of the relationship between tobacco and tumor, M Bagchi et al Also studied the protective effect of Grape Seed Extract Proanthocyanidins on the oxidative inhibition and apoptosis of human oral keratinocytes induced by tobacco extract (STE) According to statistics in the United States, about 1 / 3 of tumors are related to tobacco, and oral cancer accounts for about 3% of all tumors They used normal human oral keratinocytes to study the effects of tobacco extracts on lipid peroxidation (LP), cytochrome reduction (CCR), DNA fragment (DF) and apoptosis, and evaluated the protective effects of different antioxidants (cells were isolated from human oral tissues and treated with ste (0-300 μ g / ml) for 24 hours The formation of superoxide anion was detected by CCR, oxidative damage was detected by LP and DF, programmed cell death was detected by flow cytometry) Furthermore, the protective effects of 75 μ mol / L VC, 75 μ mol / L VE, VC + ve and 100 μ mol / L Grape Seed Extract Proanthocyanidins on these damages were compared When the cells were treated with ste of 300 μ g / ml, it was observed that LP and DF increased by 3.5-6 times, and the protection rate could reach 34% - 69% after the application of antioxidants When the cells were treated with ste of 100, 200 and 300 μ g / ml, the programmed cell death increased by 9%, 29% and 35% respectively, and the protection rate increased by 40% - 72% after the application of antioxidants Similar results can be found in LP, CCR and DF experiments The results showed that proanthocyanidins extracted from grape seeds had the best antioxidant effect The theory of anti radiation free radicals is the basic theory of radiation damage The body can produce endogenous free radicals after irradiation, which can lead to lipid peroxidation and other damage The Grape Seed Extract Proanthocyanidins have the function of scavenging free radicals and inhibiting oxidative damage According to an experimental report, mice bearing S180 sarcoma were treated with 60 Co γ - ray local irradiation, oral grape seed extract and local irradiation plus oral grape seed extract respectively On the 12th day after inoculation of tumor cells, tumor weight, leukocyte count, transformation rate of spleen lymphocyte and other indicators were detected The results showed that the average tumor weight of the control group was higher than that of the other groups; the tumor inhibition rate of irradiation plus high dose of grape seed extract was higher than that of irradiation alone and oral grape seed extract alone; the leukocyte count of irradiation alone group was lower than that of other groups The difference was statistically significant (P < 0.05) The results also showed that compared with the non irradiated group, the MDA level of the irradiated group increased, obviously related to the enhancement of lipid peroxidation and the accumulation of oxidation products in vivo However, the level of MDA was decreased by grape seed extract, and the larger the dose was, the greater the decrease was The results showed that grape seed extract could inhibit the lipid peroxidation induced by irradiation This may be the main reason that grape seed extract can resist radiation damage Russians have long known the protective effect of grape seed extract on radiation damage Soviet astronauts have long taken a plant drink rich in proanthocyanidins to prevent radiation damage during their space flight The explosion of the Chernobyl nuclear power plant in the Soviet Union caused serious nuclear pollution and many local people suffered from nuclear radiation damage People living in the area were advised to drink a red wine called Crimean, a wine rich in proanthocyanidins, to alleviate the impact of nuclear leakage on human body In a word, the anti radiation effect of grape seed extract is increasingly valued by people The rapid development of modern high technology has brought great convenience to people's life, production and work, such as television, computer, microwave oven, mobile phone, etc., which not only bring people material enjoyment, but also produce some electromagnetic radiation, endangering human health The application of grape seed extract in the production and development of some anti radiation health food will have a wide range