Knotweed, Polygonum

Two naphthoquinones, emodin (65) and physcion (66), and their glucosides were identified as allelochemicals from the rhizomes, aerial parts, and fallen leaves of giant knotweed (Polygonum sachalinense Fr. Schm.).7 In addition, the concentrations of emodin and physcion in the soil samples collected from the weed community were high enough to suppress seedling growth of susceptible plant species. 

Knotweed Polygonum Venus flytrap Dionaea muscipula... 

A similar effect is now as well ascribed to resveratrol, aphytoalexin from the skin of black grapes, and to the Japanese knotweed (Polygonum cuspidatum). The active compound, widely used in traditional Chinese herhal medicine, prevents the increased expression of human cyclooxygenase-2 and hence a higher COX-2 activity. 

Polygonum cuspidatum Siebold Zucc. Hu Chang (J apanese knotweed) (stem, root) Polygonin, glucofragulin, emodin, polydatin, flavonoids.33 Treat hypercholesterol. 

Polygonum caespitosum Blume var. longisetum (DeBruyn) A.N. Stewart knotweed, tufted... 

Pilocarpus species (pilocarpus) Piper methysticum (kava kava) Pithecollobium jiringa (jering fruit) Plantago species (plantain) Polygonum (knotweed)... 

The major dietary sources of stilbenes include grapes, wine, soya and peanut products. Trans-resveratrol and its glucoside are found in especially high amounts in the Itadori plant Polygonum cuspidatum), which is also known as Japanese knotweed (Burns etcd. 2002). It is an extremely noxious weed that has invaded many areas of Europe and North America. 

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