Abstract

We report a novel property of ethanolic extract of Emblica officinalis (amla) fruit pulp in inhibiting the growth of Helicobacter pylori in-vitro. In this study, three standard laboratory strains, and five clinical isolates of H. pylori showed sensitivity towards amla extract with minimum inhibitory concentration values ranging from 0.91 to 1.87 µg/µl. Out of five clinical isolates two were resistant to clarithromycin. The anti-H. pylori bioactive spot with retention factor (Rf) value 0.16 in toluene: choloroform: acetone (40:25:35) has been separated using thin layer chromatography followed by contact bioautography. The bioactive spot appears to be essential oil and/or phenolics. The extract contained 20.55 mg gallic acid equivalent/gm of dry weight of extract. Total reducing power was estimated to be 75.8 mg ascorbic acid equivalent per gram of dry weight of extract. Antioxidant activity was checked by 2,2'-azino-bis(3-ethylbenzthiazoline-6-sulphonic acid (ABTS), 1,1-diphenyl-2-picrylhydrazyl (DPPH) and ferric reducing antioxidant power (FRAP). Trolox Equivalent Antioxidant Capacity (TEAC) was 175.76 mg/gm of dry weight of extract when checked by ABTS assay. Thus total phenolics, flavanoids, reducing power and the antioxidant properties of amla is very well retained in the ethanolic extract and makes it suitable for a therapeutic use against H. pylori infection and gastric ulcer.

Key words: Amla, phenolics, flavonoids, contact bioautography, clarithromycin.