Activity of grape extracts from Greek varieties of Vitis vinifera against mutagenicity induced by bleomycin and hydrogen peroxide in Salmonella typhimurium strain TA102.
Mutation Research. 2006 August 24
Previuos studies have illustrated the anticancer properties of grape extracts. The aim of this study was test the anticancer activity of Greek grape extracts. A Salmonella typhimurium strain was subject to reactive oxygen species. Two grape varieties were used: Assyrtiko white grapes and Mandilaria red grapes. The DNA damage was assessed by determing the quanity of mutated bacteria. The anticancer effect of the grape extracts but also of the polyphenols quercetin, catechin, epicatechin, trans-resveratrol, gallic acid and protocatechuic acid. The researchers found that most extracts showed anticancer effect. The study concluded that chemopreventive activity of grape extract could be explained by its protection of DNA. Different phytochemicals in grapes seems to act synergistically.
Cytotoxicity of bioactive polymeric fractions from grape cell culture on human hepatocellular carcinoma, murine leukemia and non-cancerous PK15 kidney cells.
Food Chemistry Toxicology. 2006 October;44(10):1758-67
Researchers form the University of Illinois have previously isolated two fractions from grape cells with anticancer properties. The aim of this study was to investigate the slective cytotoxic effect of grape extracts on cancer cells and non-cancerous kidney cells. The researchers found that a procyanidin-rich grape extract significantly reduced viability of liver cancer cells and caused no cytotoxicity to non-cancerous kidney cells. Another phytochemical, resveratrol, is known to be cytotoxic to cancer cells but also to normal cells. The procyanidin-rich grape extract was further separated in subfractions. They found that procyanidins with higher degree of polymerization were more cytotoxic. More research is required to investigate the potential of grape extract fractions as natural anticancer agents.
Study of anticancer activities of muscadine grape phenolics in vitro.
Journal of Agricultural and FoodChemistry. 2005 November 2;53(22):8804-12
Muscadine grapes have a flowery and typical flavour but have not been studied much for content of phytochemicals. The aim of this study was to identify phenolics in the skin of muscadine grapes and to determine their ability to induce apoptosis of colon cancer cells. The phytochemicals from the skin were extracted and further separated in 3 fractions: phenolic acids, tannins, flavonols and anthocyanins. using HLB cartridge and LH20 column. The researchers found that the complete extract inhibition the colon cancer cell by 50% and that the phenolic acid and anthocyanins fractions showed this effect at a much lower dosage. Th anthocyanin fractions also induced more apoptosis of the colon cancer cells. The study concluded that polyphenols from muscadine grapes may have anticancer properties.
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