Anti-inflammatory and free radical scavenging activities of ethanol extracts of three seeds used as "Bolengguazi"

The seeds of Herpetospermum pedunculosun (Ser.) C.B.Clarke. (HPD), Mormodica cochinchinensis (Lour.) Spreng. (MCC) and Mormodica charantia L. (MCR) share the same common name ("Bolengguazi") in the Tibetan medicine. The anti-inflammatory activities of the three "Bolengguazi" were evaluated using egg album-induced paw edema and cotton-pellet granuloma tests. Among them, HPD is the most active one in both models. Results showed that oral administration of ethanol extract of HPD seed (200 and 400 mg/kg) significantly suppressed the development of egg albumin-induced paw edema (P < 0.01). In the chronic test, the ethanol extract of HPD seed (200 and 400 mg/kg) showed significant reduction in granuloma weight of rats (P < 0.05). The anti-inflammatory effect of the ethanol HPD seed was similar to that of indomethacin (10 mg/kg). Moreover, the free radical scavenging activities of "Bolengguazi" were investigated using the DPPH test. Only the ethanol extract of HPD seed showed a moderate free radical scavenging effect on DPPH (IC50, 198.69 mu g/ml) when compared with the positive control, V-E, (IC50, 44.91 mu g/ml). The HPD seeds showed more significant anti-inflammatory activities in additional to higher free radical scavenging activities than that of the MCC and MCR seeds. The results of the present study provide a scientific basis to explain, in part, the popular use of HPD seed in Tibetan folk medicine as "Bolengguazi". The present study also supports the claims by the traditional Tibetan medicine practitioners about the use of HPD seeds in inflammatory diseases, such as "Chiba". (C) 2007 Elsevier Ireland Ltd. All rights reserved.