The first results of a collaboration between researchers from the University of Rochester Medical Center and the New York, which was funded by the USDA, have been published in the Journal of Agriculture and Food Chemistry. They show that specific polyphenols that are present in large amounts in the skin and seeds of wine grapes (material usually thrown away during the wine-making process), can stand in the way of bacteria contribution to the formation of dental caries. The researchers set out to look at the make-up of polyphenols from different wine grape varieties, and to investigate how these interfere with Streptococcus mutans, (the bacteria that produces substances behind tooth decay), acid, and glucans (the building blocks of plaque). They obtained red wine grapes and pomace from wineries in the Finger Lakes area of New York state, including Pinot Noir, Cabernet Franc, Baco Noir, and Noiret, and prepared polyphenolic extracts from these. All the polyphenol extracts were seen to inhibit bacterial enzymes called glycosyltransferases (GTFs) that produce sugary glucans that stick bacteria to the surface of the tooth and protect the bacteria colonies by as much as 85 per cent. Cabernet Franc extracts were seen to be the most effective, with Pinot Noir in second place. The extracts were also seen to cause S mutans to produce significantly less acid. One proposed reason for this proposed by the researchers is that they could inhibit glycolisis, the process that turns sugar into energy, of which acid is a by-product. None of the extracts were seen to actually kill the bacteria. Despite these positive early results, lead researcher Hyun Koo said that the findings should not be taken as a signal to drink more wine. "Most foods contain compounds that are both good and bad for dental health, so the message is not 'drink more wine to fight bacteria'." But Koo added that the aim is to isolate the key compounds in winemaking waste that disarm the bacteria, and to use these in consumer products. One such product he sees as a possibility is a mouth rinse. Further chemical analysis is said to be needed to ascertain the best mix of polyphenols. While the researchers say the findings could be of particular interest in the development of drugs to support oral health and potentially to replace antibiotics, they add to a growing body of evidence for compounds found in fruit to support oral health. For instance, Koo and team have previously investigated the effects of the flavonoids quercetin and myricetin from cranberries, and their corresponding glycosides on the inhibition of GTF associated with plaque formation. They found that solutions containing 250 micrograms per millilitre of the flavonoids quercetin and myricetin inhibited the activity of GTFs by about 55 per cent in solution and by as much as 40 per cent on the hydroxyapatite. Expression of the gene responsible for producing the glucosyltransferase enzymes was said to be repressed. The use of waste material from an industrial process is an economical and environmentally friendly way to find benefit for nutrients that would otherwise be thrown away or end up in animal feed. More than 80 per cent of all grapes grown are used to make wine, and the fermented waste, known as pomace, is understood to contain at least as many polyphenols as the whole fruit. Source: Journal of Agriculture and Food Chemistry 2007 Dec 12;55(25):10200-7. Title: "Chemical characterization of red wine grape (Vitis vinifera and Vitis interspecific hybrids) and pomace phenolic extracts and their biological activity against Streptococcus mutans". Authors: Thimothe J, Bonsi IA, Padilla-Zakour OI, Koo H.