Polyphenolic compounds in the fruits of Egyptian medicinal plants ( Terminalia bellerica, Terminalia chebula and Terminalia horrida): Characterization, quantitation and determination of antioxidant capacities

• Published in: Phytochemistry (Oxford) 2010-07, Vol.71 (10), p.1132-1148
• Main Authors: Pfundstein, Beate, El Desouky, Samy K., Hull, William E., Haubner, Roswitha, Erben, Gerhard, Owen, Robert W.
• Format: Article
• Language: English
• Subjects: antioxidant activity; Antioxidants - analysis; Antioxidants - chemistry; Antioxidants - pharmacology; Antioxidative capacity; Biological and medical sciences; chebulic acid; chemical analysis; Chemical constitution; Chromatography, High Pressure Liquid; Combretaceae; ellagic acid; Ellagitannins; esters; Flavonoids - analysis; Flavonoids - chemistry; Flavonoids - pharmacology; fruits (plant anatomy); Fundamental and applied biological sciences. Psychology; gallic acid; Gallotannins; General pharmacology; glycosides; Magnetic Resonance Spectroscopy; Medical sciences; medicinal plants; medicinal properties; Molecular Structure; Pharmacognosy. Homeopathy. Health food; Pharmacology. Drug treatments; phenolic compounds; Phenols - analysis; Phenols - chemistry; Phenols - pharmacology; Plant physiology and development; Plants, Medicinal - chemistry; Polyphenols; Species Specificity; spectral analysis; Spectrometry, Mass, Electrospray Ionization; Tandem Mass Spectrometry; Terminalia; Terminalia - chemistry; Terminalia bellirica; Terminalia chebula; Terminalia horrida
• ISSN: 0031-9422; 1873-3700
• DOI: 10.1016/j.phytochem.2010.03.018

A phytochemical investigation of Terminalia bellerica, Terminalia chebula and Terminalia horrida afforded 34 compounds including two ellagic acid glycosides namely 4- O-(4″- O-galloyl-α- l-rhamnopyranosyl)ellagic acid and 4- O-(3″,4″-di- O-galloyl-α- l-rhamnopyranosyl)ellagic acid as determined by NMR. Chebulic ellagitannins display potent antioxidant capacities. Thirty-four polyphenolic substances in methanol extracts of the fruits of Terminalia bellerica, Terminalia chebula and Terminalia horrida, three plants used in Egyptian folk medicine, were initially identified by HPLC–ESI-MS and quantitated by analytical HPLC after column chromatography on Sephadex LH-20. After purification by semi-preparative HPLC the compounds were identified by their mass and fragmentation patterns using ESI-MS–MS. For several compounds detailed 1H/ 13C NMR analysis at 600 MHz was performed. Two polyphenolics, namely 4- O-(4″- O-galloyl-α- l-rhamnopyranosyl)ellagic acid and 4- O-(3″,4″-di- O-galloyl-α- l-rhamnopyranosyl)ellagic acid were identified by NMR. Antioxidant capacities of the raw fruit extracts and the major isolated substances were determined using the 1,1-diphenyl-2-picrylhydrazyl radical (DPPH), oxygen radical absorbance capacity (ORAC) and ferric reducing ability of plasma (FRAP) in vitro assays and indicated that chebulic ellagitannins have high activity which may correlate with high potential as cancer chemopreventive agents. Therefore, further studies (metabolism, bioavailability and toxicity) of the polyphenolics in Terminalia species using preclinical models and in vivo human intervention trials are warranted.