Analgesic, anti-inflammatory and toxic effects of ethanol extracts of Cucumis melo and Citrullus lanatus seeds

Plants are vital in drug discovery, since many safe and bioactive molecules have been discovered from plants in past, hence this study was designed to evaluate analgesic, anti-inflammatory and toxic effects of Cucumis melo and Citrullus lanatus. Seeds of these plants were selected due to their traditional value for medicinal use. Analgesic activity was determined in mice by Eddy's Hot plate and tail flick method, while anti-inflammatory activity was evaluated by hind paw edema method. Both seed extracts produced highly significant analgesic effects comparable to standard drugs at all three doses by both methods. The extract of C. lanatus showed significant anti-inflammatory activity at 100 mg while showed highly significant activity at 200 mg between 3 to 24 hours as compared to standard drugs. Both extracts did not reveal any mortality up to 1000mg/kg, while there was also no change in normal the gross behavior pattern of the animals at the dose of 50 and 100mg/kg, however there was increase in passivity, sedation and startle response at 200mg/kg. Analgesic and anti-inflammatory effects of extracts may be due to presence of cucurbitacin A, B or E in both seeds which are thought to inhibit COX 2. Results indicate that seeds of C. melo and C. lanatus may be effectively used as adjuvant analgesic and anti-inflammatory agents in situation of chronic pain and inflammation.