A European company now offers a red vine leaf extract containing the compounds believed to correspond to the healthy effects associated with the French Paradox. EFLA®945 Vitis vinifera Special Extract from Emil Flachsmann AG, Wadenswil, Switzerland, contains standard amounts of polyphenols, anthocyanins and trans-resveratrol.
The highest levels of anthocyanins are found in red vine leaves in the autumn, between the grape harvest and the time the leaves are shed from the vine. They are responsible for red and blue coloration of the leaves. Malvidin glucosides are the main anthocyanins in the leaves. Also occurring are delphinidin, cyanidin and pertunidin glucosides. Tannins from the catechin group are prominent in the leaves. The phytoalexin trans-resveratrol is a metabolite produced in response to UV light, fungal infection or physical injury, and also can be found in the red vine leaf.