Rheum species

Stilbenes are naturally occurring phytoalexins found in medicinal plants of Polygonum species and Rheum species (Polygonaceae) [10,11]. Among... 

RHUBARB ROOT, Rhei radix Medicinal Rhubarb consists of the peeled and dried root of Rheum species, chiefly Rheum officinale Baill. and R. palmatum L., family Polygonaceae, but not of Rheum rhaponticum... 

AGARWAL s K, SINGH s s, LAKSHMi V, VERMA s and KUMAR s (2001), Chemistry and pharmacology of rhubarb Rheum species) - A review , J. Sci IndRes, 60, 1-9. 

Xiao PG, Chen BZ, Wang LW, Ho LY et al. 1980 A preliminary study of the correlation between phylogeny, chemical constituents and therapeutic effects of Rheum species. Yao Hsueh Hsueh Pao 15 33-39... 

Rhein is found in various Cassia and Rheum species. 

Chrysophanol ( chrysophanic acid ) is present in Aloe and Rheum species. 

Chrysophanol, l,8-dihydroxy-3-methyl-9,10-anthracenedione, an anthraquinone, occurs in the free state and as a glucoside in various plants, notably Aloe species and Rheum species. It is listed by many sources as synonymous with chrysophanic acid Merck Index, 1996 WHO, 1999) and is listed by the Colour Index (1971) as Cl 75400. 

The anthraquinone compound Rhein, 1,8-dihydroxy an-thriquinone-3-carboxylic acid, is found in various Cassia and Rheum species MerckIndex, 1996). It is also known as rhubarb yellow . 

Source Chinese rhubarb Rheum officinale Bail ., R. palmatum L., R. tanguticum Maxim, ex Reg., and other Rheum species or hybrids grown in China Indian rhubarb... 

Rheum palmatum (rhubarb) Aconitum napellus (monkshood) Cimicifuga racemosa (black cohosh) Delphinium species (delphinium) Hydrastis canadensis (golden seal) Pulsatilla species (pasque flower) Ranunculus damascenus (buttercup)... 

Botanical name Rheum officinale Rheum palmatum and the variety tanguticum and probably other species... 

Emodin (l,6,8-trihydroxy-3-methylanthraquinone), the active principle of Polygonum cuspidatum (Polygonaceae), was reported to be an inhibitor of the p56 -PTK activity from bovine thymus, with an IC50 of 18.5 pM. When the hydroxyl functions at C-6 or C-8 were blocked by methylation or glycosylation, respectively, the effect disappeared. The inhibition was competitive with respect to ATP and non competitive with respect to the substrate [64]. In a bioassay-guided separation of the anthraquinones found in rhizomes of another Polygonaceae species, rhubarb Rheum... 

In this study, attempts have been made to address collection, domestication and ex-situ conservation of four species (Angelica glauca, Arnebia benthamii, Rheum emodi and Pleurospermum angelicoides) using different agrotechnology (polyhouse, shade net etc.) in order to reduce pressure on these species in their natural habitats. 

The dried root, deprived of the bark, from one or more undetermined species of Rheum. Grows in China, Chinese Tartary, and Thibet. Imported from Shanghai and Canton, and brought overland by way of Moscow. 

C15H10O5. Mr 270.24, orange needles, mp. 223 - 225 °C, uv 430 nm (C2H5OH), soluble in ether, benzene, and hot ethanol. A. is named after the aloe, the concentrated leaf juices of various Aloe species (A. ferox, A. barbadensis, Liliaceae) and occurs additionally in free form and as the corresponding anthrone glycosides in Rhamnus, Rheum, Rumex, and Cassia species. In addition to laxative action it also exhibits an antileukemic effect and is used as starting material for the synthesis of anthracycline antibiotics. 

L. D (xanthokermesic acid) [yellow needles, mp. >300°C (decomp.), uv ,j 345 nm] exhibits laige structural differences to the L. A-C and also occurs in Rheum- and Cassia species. ... 

Constituent, of variod s species of rhubarb Rheum), of cassia, goa, etc. Golden-yellow cryst. M.p. 196". Sol. MejCO, AcOH, CHClj, hot EtOH, hot C,PL. Spar. sol. HgO, ligroin, Et,0. Sublimes, (jonc. H Og —> red col. Sol. caustic alkalis, hot alk. c bonates Zn dust dist.—>. 2-methylanthiacehe. 

Secondary compounds with similar structures, for example, polygonaquinone (5) (Figs. 6.1 and 6.2), are encountered in species of Fagopyrum (buckwheat). Polygonum (smart-weed), Rumex (dock), and Rheum (rhubarb) in the Poly-gonaceae (Mathis, 1966). 

Anthraquinone glycosides have long been used medicinally as cathartics and laxatives. Plant-derived drugs of this type include aloes Aloe species), cascara sagrada (Rhamnus purshiams), frangula (Rhamnus frangula), rhubarb (Rheum officinale), rumex or yellow dock (Rumex crispus) and senna (Cassia spp.). Many of the commercial preparations (patent medicines) based on these plants are readily available. 

Hydroxystilbenes are found in a variety of plants, many unrelated. They are a prominent component of many species of the Poly-gonaceae family Rheum, Polygonum spp.) but the richest source is found in grape skins and red wine (Creasy and Creasy 1998). 

Stilbenes originate from the same biosynthetic precursors as flavonoids, but have a different structure, since the polyketide portion undergoes a different type of cyclization including loss of one carbon by decarboxylation. Stilbenes occur in several umelated plants such as peanut (Arachis hypogaea), grapevine (Vitis vinifera), rhubarb (Rheum), false hellebores (Veratrum) and pine (Pinus) species. These compounds have antifungal properties. They are induced upon stress, injury, and fungal infection and can therefore be classified as phytoalexins. 

Emodin is found mostly as a rhamnoside in various Rhamnus, Rheum and Cassia species. 

Emodin, l,3,8-trihydroxy-6-methylanthraquinone, is an anthraquinone dye which occurs mostly as a rhatrmoside (see Frangulin) in various Rhamnus, Rheum and Cassia species. It is a major dye component extracted from the bark of Cassia fistula L. Also known as frangula emodin and rheum emodin Merck Index, 1996 Schweppe, 1992). 

Occurs in various species used for pigment production, including Aloe and Cassia, and probably also Rheum... 

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