English name:Giant Knotweed Extract Plant origin:Polygonum cuspidatum Sieb. et Zucc. Aspect:Fine Brown to white Powder Active ingredient:Resveratrol (trans) CAS NO. :501-36-0 Molecular Weight:228.24 Molecular formula:C14H12O3 Specification:50% 98% Resveratrol (HPLC)