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

ABSTRACT

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<0.01) of exudation induced by carrageenan, and 60.88%±0.14 (p<0.01) of leukocyte migration to the pleural cavity. In conclusion, the results validate the technological conditions of the maceration process to produce an optimized bioactive herb extract for the development of analgesic and anti-inflammatory phytopharmaceuticals using 70 ºGL ethanol, a plant to solvent ratio of 12.5% (w/v), and ten days of maceration.