ABSTRACT
Olea europaea (Oleaceae) leaves of 14 different cultivars have been studied by a new isocratic HPLC method. Qualitative and quantitative determinations of principal compounds were established for each cultivar. Oleuropein concentration was determined for each sampled tree, using coumarin as internal standard. Bid el Haman, Chemlali, Meski, Cailletier, Tanche, a Verdale-Picholine hybrid, and Lucques, in particular, had high oleuropein concentrations and could be useful sources for industrial extractions.
Subject(s)
Phenols/chemistry , Plant Leaves/chemistry , Plants, Medicinal/chemistry , Pyrans/analysis , Antihypertensive Agents/analysis , Antihypertensive Agents/chemistry , Chromatography, High Pressure Liquid/methods , Iridoid Glucosides , Iridoids , Magnoliopsida/chemistry , Phenols/analysis , Pyrans/chemistry , Species Specificity , Trees/chemistryABSTRACT
The study of the metabolism of iridoid glycosides from Harpagophytum procumbens and Harpagophytum zeyheri by human intestinal bacteria, was realized in order to elucidate compounds responsible for the pharmacological activities of Harpagophytum. Harpagide, harpagoside and 8-O-p-coumaroyl-harpagide were transformed into the pyridine monoterpene alkaloid aucubinine B by human fecal flora and by bacteria isolated from this flora. Aucubinine B was also prepared from harpagide, harpagoside and 8-O-p-coumaroylharpagide, by beta-glucosidase in the presence of NH4+.
Subject(s)
Alkaloids/chemical synthesis , Bacteria/metabolism , Coumaric Acids/metabolism , Glycosides , Intestines/microbiology , Plants/metabolism , Pyrans/metabolism , Pyridines/chemical synthesis , Coumaric Acids/chemistry , Humans , Iridoid Glycosides , Magnetic Resonance Spectroscopy , Nitrogen/chemistry , Pyrans/chemistryABSTRACT
The treatment of harpagide (1), harpagoside (2), or 8-O-p-coumaroylharpagide (3), the main iridoids of Harpagophytum procumbens and Harpagophytum zeyheri, with NH3 and HCl led to aucubinine B(4), a pyridine monoterpene alkaloid (PMTA). A similar procedure applied to a commercial extract of H. procumbens yielded 4 and two new PMTAs named beatrine A (5) and beatrine B (6). The structures of these new PMTAs were established using ESIMS and 2D NMR. Their semisynthesis was analyzed in terms of reaction mechanisms.
ABSTRACT
The iridoids of Harpagophytum procumbens and Harpagophytum zeyheri were studied by CLHP. Harpagoside is the main iridoid for both drugs whereas 8-p-coumaroylharpagide is a representative iridoid of Harpagophytum zeyheri only. The ratio harpagoside/8-p-coumaroylharpagide can be used to distinguish chemically both species. For commercial dried aqueous extracts this ratio is intermediate because they are probably prepared from a mixture of H. procumbens and H. zeyheri drugs. The aqueous extracts of both drugs show similar analgesic and anti-inflammatory properties. Harpagophytum procumbens and Harpagophytum zeyheri should be accepted as sources for the drug Harpagophyti radix.
