Abstract: Objective: To investigate the antiinflammatory, analgesic and in vitro antioxidant effects of turmeric oil. Methods: Xylene-induced mouse ear swelling and carrageenan-induced mouse paw swelling tests were used to comprehensively evaluate the antiinflammatory effect. The analgesic effect of continuous intragastric administration of turmeric oil was evaluated by hot plate pain threshold and the number of writhing responses induced by acetic acid. The in vitro antioxidant activity was investigated by determining the scavenging capacity against 1,1-diphenyl-2-picrylhydrazyl (DPPH) and superoxide anion free radicals, total antioxidant capacity and inhibitory effect on lipid peroxidation. Results: Turmeric oil at different doses showed different antiinflammatory and analgesic effects. At the same time, both gastrointestinally digested and native turmeric oil had good antioxidant effect in a dose-dependent manner. Total antioxidant capacity of turmeric oil was better with a half maximal effect (EC50) of 0.75 mg/mL. Overall, however, the antioxidant effect of gastrointestinally digested turmeric oil was better than that of its untreated counterpart.

Key words: turmeric oil, antiinflammatory activity, analgesic activity, in vitro antioxidant activity