Anti-inflammatory activity and chemical composition of Pycnocycla bashagardiana fruit’s essential oil in animal models

Objectives Pycnocycla bashagardiana is an endemic species found only in Iran. Due to the presence of myristicin as the major component of the fruit's oil we were prompted to assess the antinociceptive and anti-inflammatory properties of P. bashagardiana fruit's essential oil (PBFEO). Materials and Methods The analgesic activities of PBFEO (100, 200, and 400 mg/kg, IP) were studied by hot-plate and formalin tests in mice. Control and standard groups received vehicle and morphine (5 mg/kg, IP), respectively. The acute anti-inflammatory effect of PBFEO (200 and 400 mg/kg, IP) were assessed by carrageenan-induced paw edema method in 30 min, 1, 2, 3, and 4 hr after carrageenan injection and the chronic anti-inflammatory effect of PBFEO (50 and 100 mg/kg, IP) were assessed by the cotton pellet-induced granuloma method in rats. Results In hot-plate and formalin tests, the studied doses of PBFEO were not effective. However, in carrageenan test, all studied doses of PBFEO significantly reduced the paw edema in comparison to the control animals (P<0.05). Anti-inflammatory activity of PBFEO (200 and 400 mg/kg, P<0.05) was found to be more than mefenamic acid (30 mg/kg). In cotton pellet-induced granuloma, PBFEO was also effective regarding the transudate and granuloma formation amount. PBFEO was analyzed by gas chromatography-mass spectrometry and 12 constituents, representing 96.0% of the oil, were identified. The major component of the oil was characterized as myristicin which might be responsible for the anti-inflammatory activity. Conclusion The results suggest that PBFEO possesses biologically active constituents that have significant peripheral anti-inflammatory effects.