Antioxidant activity grape seeds

Natural products have been noted for their potential health benefits from time immemorial and are the basis of Ayurveda, an ancient Indian medical practice (Bushkin and Bushkin, 2002). However, the potential benefits of several natural products reside in one or two active ingredients. For example green tea stands for polyphenols, soy for soy estrogens, broccoli for isothiocyanates and grape seed for polyphenols. The beauty of rice bran is that there are more than 100 antioxidants, several categories of bioactive phytonutrients, such as IP6, polyphenols, phytosterols, tocotrienols, y-oryzanol, B vitamins, minerals and trace minerals in addition to fat, protein, fiber, polysaccharides and other nutrients. These phytonutrients and antioxidants of rice bran are believed to act at the cellular level, and their synergestic function is responsible for the positive health benefits. 

Grape seed extract, which is another widely used plant extract similar to pycnogenol, contains procyanidins, which have a strong antioxidant activity. 

N10. Nuttall, S. L., Kendall, M. J., Bombardelli, E., and Morazzoni, P., An evaluation of the antioxidant activity of a standardized grape seed extract, Leucoselect. J. Clin. Pharm. Ther. 23,385-389 (1998). 

Therefore inorganic sunscreens commonly used in cosmetic industry should be carefully tested for their photoactivity and phototoxicity. Sunscreens based on titanium and zinc oxides should contain additional antioxidants, eg a-tocopherol or j5-carotene. Even more efficient protection against unwanted ROSs can be achieved by a smart titanium dioxide modification that would block its photocatalytic activity. Recently Lee et al. described a hydrophobic multicomponent polymer coating for nanocrystalline Ti02 containing natural antioxidants extracted from grape seeds... 

Grape seeds are rich in polyphenols, especially flavanols (catechin, epicatechin) and gallic acid (Meyer et al., 1997). When grape extracts are prepared after crushing of the seeds, increased levels of phenols are obtained compared with extracts prepared with intact grape seeds. In particular, flavan-3-ol levels increased significantly. The antioxidant activity, as measured by the ability to inhibit LDL oxidation, also increased when the seeds were crushed prior to extraction. 

Jayaprakasha, G. K., Singh, R. P., and Sakariah, K. K. (2001). Antioxidant activity of grape seed (Vitis vinifera) extracts on peroxidation models in vitro. Food Chem. 73,285-290. 

It is the antioxidant isolated from the bark of a pine tree by Masquelier, a French chemist. This was about 50 years ago. The active principal is OPC, which is found in grape seeds. 

The product quality has been analyzed with respect to the retention of the antioxidant activity of the spray-dried powder. Polyphenolic compounds present in several extracts (grape seed, apple polyphenolic extract, or olive-leaf) were also encapsnlated by SD in protein-lipid emulsions (Kosaraju et al, 2008) and chitosan (Kosaraju et al., 2006). 

Grape seed extract (GSE) has proven antioxidant activities both in vivo and in vitro in various meat products [163-167]. In the meat system, GSE proves its antioxidant... 

Peng X, Ma J, Cheng K-W, Jiang Y, Chen F, Wang M (2010) The effects of grape seed extract fortification on the antioxidant activity and quality attributes of bread. Food Chem 119 49-53... 

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