Resveratrol

Resveratrol is a natural polyphenolic compound, specifically a stilbenoid and phytoalexin, found primarily in the skins of red grapes, berries, peanuts, and red wine. It is produced by plants as a defense mechanism against stressors such as fungal infections, ultraviolet radiation, and mechanical injury. In the supplement industry, it is most commonly extracted from the Japanese knotweed (Polygonum cuspidatum) due to its high concentration of the bioactive trans-resveratrol isomer.