Plant Origin:Polygonum cuspidatum Specification :20%, 50%, 80%, 98% HPLC Product Name: Resveratrol 20% Botanical Name: Polygonum cuspidatum Plant Part: Roots Extract Solvent: 90% Ethanol Extract Ratio: 100:1 approx. Carrier Used: None Appearance:Fine Powder Color:Brown Odor:Characteristic Taste:Characteristic Particle Size:100% through 80 Mesh Moisture:< 5.0% Heavy Metals:< 20ppm Arsenic (As) :< 1ppm Assay Resveratrol by HPLC:>20% Total Plate Count:1,000cfu/G Yeast & Mold:< 100cfu/G E.Coli.:Negative Salmonella:Negative Shelf Life:Two years when properly stored. Storage:Tightly sealed in a clean, cool, dry area. Do not freeze, keep away from strong, direct light.