Objectives:This study was aimed to evaluate the chemical composition, antioxidant potential in vitro and in vivo, anti-inflammatory, and antinociceptive activity of turmeric oil.Materials and Methods:Chemical analysis of turmeric oil was done by gas chromatography/mass spectrometry. Antioxidant activities in vitro was done by six different methods and in vivo antioxidant activity was determined by measuring superoxide generation from macrophages treated with phorbol-12-myristate-13-acetate (PMA) as well as determining antioxidant level after feeding the oil orally for one month. Anti-inflammatory activity was studied in mice using carrageenan, dextran, and formalin. Antinociceptive activity was evaluated by using acetic acid-induced writhing movement in mice.Results:The main constituent of essential oil of turmeric was found to be ar-turmerone (61.79%), curlone (12.48%), and ar-curcumene (6.11%). Turmeric oil was found to have in vitro antioxidant activity and IC50 for scavenging superoxides, hydroxyl radicals, and lipid peroxidation were 135 μg/ml, 200 μg/ml, and 400 μg/ml, respectively. The ferric-reducing activity for 50 μg of turmeric essential oil was found to be 5 mM. Intraperitoneal administration of oil was found to inhibit PMA-induced superoxide radicals elicited by macrophages. Oral administration of turmeric oil for one month to mice significantly increased superoxide dismutase, glutathione, and glutathione reductase enzyme levels in blood and glutathione-S-transferase and superoxide dismutase enzymes in liver. Turmeric oil showed significant reduction in paw thickness in carrageenan, dextran-induced acute inflammation, and formalin-induced chronic inflammation. The drug produced significant antinociceptive activity (P < 0.001) at all doses studied.Conclusions:These results demonstrated that turmeric oil has potential health benefits as it can scavenge the free radicals and produce significant anti-inflammatory and antinociceptive activities.

Zingiber officinale Roscoe, ginger, is a major spice extensively used in traditional medicine. The toxicity profile of ginger oil was studied by subchronic oral administration for 13 weeks at doses of 100, 250, and 500 mg/kg per day to 6 groups of Wistar rats (5/sex per dose). Separate groups of rats (5/sex per group) received either paraffin oil (vehicle) or were untreated and served as comparative control groups. There was no mortality and no decrease in body weight or food consumption as well as selective organ weights during the study period. Administration of ginger oil to rats did not produce any treatment-related changes in hematological parameters, hepatic, renal functions, serum electrolytes, or in histopathology of selected organs. The major component of ginger oil was found to be zingiberene (31.08%), and initial studies indicated the presence of zingiberene in the serum after oral dosing. These results confirmed that ginger oil is not toxic to male and female rats following subchronic oral administrations of up to 500 mg/kg per day (no observed adverse effect level [NOAEL]).