Knotweed Extract

Knotweed extract is obtained from the root and rhizome of giant knotweed (Polygonum cuspidatum, also classified as Reynoutria japonica), a perennial of East Asia. Nustras supplies it as a water and ethanol extract, a red-brown fine powder standardised to its resveratrol content, for use as a botanical ingredient in supplements and cosmetics. The root is one of the richest natural sources of trans-resveratrol, a stilbene polyphenol.

Knotweed extract is formulated into capsules, tablets and softgels for the supplement trade, into powdered blends and functional beverages, and into cosmetic and skincare preparations where a resveratrol-rich botanical is wanted.

The material is a red-brown fine powder with a faint characteristic odour. Resveratrol content is standardised to specification and confirmed by HPLC on each lot, and identity is verified against the botanical reference. Loss on drying, residual solvents, heavy-metal, pesticide and microbial limits are supplied to specification and confirmed on each lot's certificate of analysis.

Nustras supplies knotweed extract in bulk commercial quantities, in food-grade bags and fibre drums, to manufacturers and formulators internationally, with a certificate of analysis, specification sheet and country-of-origin documentation on every lot. Knotweed-derived resveratrol is an accepted supplement ingredient in major markets; buyers confirm the permitted plant part, purity and claim for their application. Contact us for grade, pricing per kilogram and lead time.