Development of hydroethanolic extract of Ipomoea pes-caprae using factorial design followed by antinociceptive and anti-inflammatory evaluation

Ipomoea pes-caprae (L.) R. Br., Convolvulaceae, is a medicinal plant that grows abundantly as a pan-tropical stand plant. The 3² (two factors and three levels) factorial design, was applied to determine the best time and drug/solvent proportion to maximize the flavonoid content in the hydroethanolic extract by maceration process. The antinociceptive and anti-inflammatory effects were studied at 5-20 mg/kg, i.p., using the writhing test and carrageenan-induced pleurisy models in mice. The optimized extract was able to inhibit more than 50% of abdominal writhing at 20 mg/kg, with 55.88%±2.4 of maximum inhibition. Indomethacin, used as positive control, inhibited 64.86% at 10 mg/kg. In the pleurisy model, the extract produced dose-dependent inhibition of the first phase of inflammation (4 h) in the pleural cavity induced by injection of carrageenan (1%) in mice. It inhibited 50%±0.82 (p