Object of our study was the research on the chemical composition of grapes of Greek varieties and their corresponding wines, as well as the investigation of the biological role on the system of detoxication of the organism via the enzymatic system of the transferase of glutathion (GST) in vitro and in vivo. The aim is to choose the wine compounds presenting an action on Ras and play role as chemically protective agents.
The first results are encouraging especially those about the grapes of Mandilaria of Santorini. We found that these grapes were very rich in resveratrol (150 mg/kg of grapes), amount extremely high according to recent bibliographic references. These results were confirmed following two consecutive vintages. Trans-Resveratrol may be one of the most active compounds of red wines that have been shown in a number of studies to confer protection against atherosclerosis and coronary heart disease. It is known that resveratrol is produced by grapes in response to fungal infection and UV irradiation. The variety of grapes also plays an important role in resveratrol synthesis which can be genetically controlled. Thus, it is possible that the greater sun exposure of Mandilaria in Santorini may be a factor for the increased levels of resveratrol. Trans-resveratrol was not detected in samples of the same variety from other regions. Probably the climate conditions in Santorini contribute to the high levels of this compound.
Furthermore, in a parallel research it was shown that quercetin prevents the multiplication of cancer cells even in lower concentrations than other polyphenolic compounds.
S. Charoutounian, Agricultural University of Athens, Greece
G. Kazantzoglou, L. Skaltsounis, Pharmaceutical Department of Athens, Greece
Y. Kotseridis, Agricultural University of Athens - KEOSOE, Greece
F. Psachoulia, A. Pintzas, National Research Institute-Athens, Greece