Phytochemical investigation and anti-inflammatory activity of aerial parts of Stachys byzanthina C. Koch.

From the aerial parts of Stachys byzanthina C. Koch., an acyclic diterpene ester, phytyl nonadecanoate, was isolated for the first time. In addition, two normal alkanes, one fatty acid and two sterols were also identified. Stuctures were established by conventional methods of analysis and confirmed by 1H, 13C NMR and mass spectral analysis. Anti-inflammatory effects of acetone and methanolic extracts of aerial parts of Stachys byzanthina C. Koch. were investigated in this study. For assessment of anti-inflammatory properties, two well-characterized inflammatory models, formalin test and carrageenan-induced paw edema were used. Intraperitoneal injections of either acetone or methanolic extract of Stachys byzanthina C. Koch. (50, 100 and 200 mg/kg), 30 min before formalin injection, had no effects against the first phase of the formalin-induced pain, but all three doses caused a significant blockade on the second phase (p < 0.01). The recording of the early phase started immediately after formalin injection and lasted for 10 min (0-10 min). The late response was recorded 20 min after formalin injection and lasted for 10 min (20-30 min). In the carrageenan-induced paw edema, both extracts revealed dose-related inhibitory effects on carrageenan-induced rat paw edema over the dose range 50-200 mg/kg. The anti-inflammatory activities of these extracts were similar to a high dose of indomethacin (5 mg/kg) in both carrageenan-induced paw edema and formalin-induced paw licking. In conclusion, the present data provide further evidence for an important role of extracts of Stachys byzanthina C. Koch. in the inhibition of pain and inflammatory processes.