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knotweed, a genus of annual and perennial herbs, less frequently, semishrubs and shrubs, of the family Polygonaceae. Their stems are erect, prostrate, or sometimes twining. The perianth is usually a corolla of four to six small leaves: there are four to eight stamens and two to three styles. The fruit is triquetrous or lenticular, remaining more or less fully enclosed in the perianth. There are 300 species, mostly found in temperate and tropical regions. In the USSR there are more than 120 species.

From a biological point of view several species are particularly interesting. Willowgrass (Polygonum amphibium) is found in two forms, an aquatic one and one growing in moist places (one form is capable of transforming into the other); serpent grass (P. viviparum) has lower flowers that are mostly turned into bulblets and used for vegetative propagation. Many members of the genus have economic value. Bistort (P. bisunta), peachwort (P. persicaria), knotweed (P. aviculare), and several others are used in medicine. The extract or infusion of the dried terrestrial sterile and fertile stems of water pepper (P. hydropiper) is used as an an-tihemorrhagic substance, primarily in the case of uterine hemorrhages; it is also part of the composition of the antihemorrhoidal “anestezol” suppositories. Middle Asian representatives of the genus known by the name alpine knot-weed (P. alpinum, P. coriarium, and others) are used as tanning substances.

Knotweed. black bindweed (P. convolvulus), and copse knotweed (P. dumetorum), are weeds. The last two species, as well as the cultivated (as an ornamental) fleece flower (P. baldschuanicum), are often distinguished as a separate genus, Bilderdykia. Three species of Polygonum—Sakhalin knotweed. cuspidate knotweed. and Weirich knotweed, all with a large amount of greenery—are good fodder plants. Many members of the genus are good nectar plants. Some species—for example, P. tinctorium—can be used to obtain dyes.


Atlas lekarstvennykh rastenii SSSR. Moscow, 1962.
Webb, D. A., and A. O. Chater. “Polygonum L.” In Flora Eu-ropaea, vol. 1. Cambridge, 1964.


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Polygonum hiekmanii (Polygonaceae), a new species from California.
At week 2 the Polygonum group had black colouration in the regrowing hair, while neither less visible hair growth nor black colouration was observed in the control group.
Editor's note: It is possible that Polygonum cuspidatum has other beneficial compounds in addition to resveratrol.
For example, Polygonum pensylvanicum, a colonizing annual of open fields, had an [A.
Related botanical works regarding the anatomy of emergent aquatic macrophytes of the Parana River floodplain are scarce; one could mention the one by Silva-Brambilla and Moscheta (2001), which discusses the leaf anatomy of six species of Polygonum.
Malvaceae Hong-rang-paing Leaf, flower rosa sinensis L Polygonum Polygonaceae Mra-che-bang Leaf, root hydropiper L.
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Inhibitory effects of Polygonum cuspidatum water extract (PCWE) and its component rasveratrol on acyl-coenzyme Acholesterol acyltransferase activity for cholesteryl ester synthesis in HepG2 cells.
5 Polygala polygama (racemed -- -- -- milkwort) * (T) Polygonatum biflorum (smooth solomon's -- -- -- seal) * Polygonum convolvulus (black bindweed) 2.
China has a tradition of using natural ingredients derived from herbs such as pearl, polygonum multiflorum, and aloe, which are believed to be good for your health," said Kim Li, the manager of business development at industry consultants Frost & Sullivan China.