Anti-inflammatory activity and toxicity of the standardised water extract of Phyllanthus emblica L.

Phyllanthus emblica L. is an herbal plant commonly used in Asian traditional medicine. Its fresh or dry fruits were reported as an alternative treatment of diarrhea, jaundice, and inflammatory disorder [1, 2]. The aim of this study was to investigate anti-inflammatory activity and toxicity of a standardised water extract of P. emblica fruits prepared according to Thai Herbal Pharmacopoeia. Its anti-inflammatory activity was tested in rats using carrageenan-induced paw edema and cotton pellet-induced granuloma models. Acute (5,000mg/kg) and chronic oral toxicities (300, 600, and 1,200mg/kg) were also evaluated in rats. Oral administration ofP. emblica extract at the doses of 150, 300, and 600mg/kg caused dose-dependent inhibition of carrageenan-induced acute inflammation (Table 1). In chronic inflammation, P. emblica (600mg/kg) did not reduce both transudative and proliferative phases, body weight gain and thymus weight in cotton pellet-induced granuloma formation (data not show). The pharmacological mechanism of activity of the standardised water extract of P. emblica seems to be more similar to NSAIDs rather than to steroidal drugs. Inhibitory effect on the synthesis and/or release of inflammatory mediators, especially prostaglandins, may be the main mechanisms of action of P. emblica water extract. In addition, P. emblica water extract did not produce acute (LD50 >5,000mg/kg) and chronic oral toxicity. The extrapolation of these results to humans suggests that Phyllanthus emblica L. water extract should be acceptably safety level for usage at the doses of 300, 600, and 1,200mg/kg/day.

Acknowledgements: Royal Golden Jubilee Ph.D. Program and the National Research Council of Thailand

References: 1. Santisuk, T. et al. (2005) Floral of Thailand. Vol. 8 Part 1 (Euphorbiaceae). Prachachon. Bangkok.

2. Khan, KH. (2009). Bot Res Intl 2(4): 218–28.