Combretum

There is a need to have a testing regime to ensure that the gum acacia offered is gum acacia and not a product from some other species that is unsuitable. Acacia Seyal gum is sometimes encountered, which is less soluble than gum acacia and hence it is unsuitable for making sweets with a high proportion of gum acacia as it will not dissolve sufficiently. Instances have occurred where gum combretum, a product that is not an acacia gum, has been found in commercial supplies purporting to be gum acacia. 

Combretastatins are a class of compounds originally derived from the African Willow tree (Combretum caffrum) and are powerful reversible inhibitors of tubulin polymerization. This class of molecules has been shown to bind to the colchicine binding site of tubulin, by the same mode of action as mentioned above (Sect. 1.2). Combretastatins consist of a ris-slilbcnc core structure. To date, there have been several compounds that have shown promise as potential anticancer drugs. However, development of these compounds as anticancer agents is limited by issues of chemical stability, bioavailibilty, toxicity, and solubility. 

This approach has been chosen to investigate the active principles of kinkeli-ba, a decoction of the leaves of Combretum micranthum, used against tropical fevers, bilious alimentary disorders, colic, and vomiting. No appreciable activity could be demonstrated for the isolated alkaloids (hydroxystachydrines) (65). 

To produce validated methods for the identification and quantification of the following gums in foodstuffs Acacia Senegal gum, A. seyal gum, A. combretum gum, carrageenan and alginates. 

Extracts of leaves of Combretum quadrangulare showed promising hepatoprotective effect on D-GalN or tumor necrosis factor-a (TNF-a)-induced cell death in primary cultured mouse hepatocytes. The hepatoprotective effect of C-glycosylflavones from C. quadrangulare was determined by evaluation of the serum enzyme level in comparison with the o-GalN or TNF-a treated control. At the concentration of 200 pg/ml, orientin and isoscoparin possessed an inhibitory effect on TNF-a-induced cell death of about 20%, while vitexin at 100 pg/ml produces a 95%i inhibitory effect. 

Banskota, A.H. et al., Hepatoprotective effect of Combretum quadrangulare and its constituents, Biol. Pharm. Bull, 23, 456, 2000. 

Masoko P, Eloffa JN. Screening of Twenty-Four South African Combretum and Six Terminalia Species (Combretaceae) for Antioxidant Activities. African Journal of Traditional, Complementary and Alternative medicines. 2007 4(2) 231-239. 

Studies on Uronic Acid Materials. II. The Variation in Composition of Gum Nodules from Combretum leanense, D. M. W. Anderson, E. L. Hirst, and N. J. King, Talanta, 3, 118 (1959). 

Combretastatin A4 phosphate (72) is a phosphate prodrug of combretastatin A4, a c/s-stilbene, isolated from Combretum caffrum (66). Combretastatin A4 is one of the many combretas-tatins that inhibits tubulin polymerization (67), shows efficacy against solid tumor, is a vascular targeting agent that blocks the blood supply to solid tumors, and is in Phase II/III clinical development for the treatment of various types of tumors as a vascular targeting agent (68-71). 

Combretum 11, Albizzia 12, Anogeissus latifolia 13, Khaya 14, Astragalus 15, Sterculia urens 16, other Sterculia 17, Bombax malabaricum 18, Cochlospermum gossypium 19, Feronia elephantum 20,... 

The combretastatins are a group of antimitotic agents isolated from the bark of the South African tree Combretum caffrum. A novel and highly stereoselective total synthesis of both the c/s and trans isomers of combretastatin A-4 was developed by J.A. Hadfield and co-workers.The (Z)-stereoisomer was prepared using the Perkin reaction as the key step in which 3,4,5-trimethoxyphenylacetic acid and 3-hydroxy-4-methoxbenzaldehyde was heated with triethylamine and acetic anhydride at reflux for several hours. The a,p-unsaturated acid was isolated in good yield after acidification and had the expected ( ) stereochemistry. Decarboxylation of this acid was effected by heating it with copper powder in quinoline to afford the natural product (Z)-combretastatin A-4. 

Cannabis sativa Cereus jacamaru Combretum zeyheri... 

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