Knotweed Extract

Giant knotweed, or Japanese Knotweed, Reynoutria japonica, polygonum cuspidatum, is a species of herbaceous perennial plant of the knotweed and buckwheat family Polygonaceae. It is commonly known as Asian knotweed or Japanese knotweed. It is native to East Asia in Japan, China and Korea. In North America and Europe, the species has successfully established itself in numerous habitats and is classified as a pest and invasive species in several countries.
Japanese knotweed extract is the main source of  stilbenes (resveratrol) or anthraquinones (emodin), which the medicine effects work. Resveratrol is the main active ingredient in knotweed extracts, is a non-flavonoid polyphenolic compound that is an antitoxin produced by many plants when stimulated. It is used in traditional Chinese and Japanese medicine to treat various disorders through the actions of resveratrol, although there is no high-quality evidence from clinical research for any medical efficacy. Extracts of resveratrol from Japanese Knotweed roots are higher in content than those from stems or leaves and have the highest levels at the end of the growing season.