... 1. Polygonum Cuspidatum Extract Resveratrol 2. Test Method: HPLC 3,Speciafication:50%98% 4.Strong antioxidant 5.Free sample What is resveratrol: Resveratrol ( ... , spruce, resveratrol's most abundant natural sources are Vitis vinifera, labrusca, and muscadine grapes, Polygonum cuspidatum Sieb.Cardiovascular Effects ... years if sealed and store away Polygonum Cuspidatum Extract Resveratrol Powder