ABSTRACT
In recent years, a widespread search has been launched to identify new antiinflammatory and antiulcer-drugs from natural sources. The study was aimed at evaluating the antiinflammatory and antiulcer activity of chloroform extract (CH) and hydroalcoholic extract (HE) of the stem bark of Calotropis procera (Aiton) W.T. Aiton, Apocynaceae, obtained successively by cold maceration. The antiinflammatory effect of the CH and HE extracts of the stem bark of the C. procera against carrageenan-induced paw oedema and also its antiulcer activity by using two acute models: Aspirin (100 mg/kg, p.o.) and ethanol (96 percent, 1 mL/200 g) in albino rats have been studied and found to be significant at 200 and 400 mg/kg when compared to the standard drugs. As a part of investigations to obtain compounds with antiinflammatory and antiulcer activity in this work, a bioassay was carried out with fractions obtained from chloroform extract with n-hexane (NF1), 1-butanol (BF1), ethyl acetate (EF1) and chloroform (CF1). The hydroalcoholic extract (HE) of the stem bark was fractionated with n-hexane (NF2), 1-butanol (BF2), ethyl acetate (EF2), chloroform (CF2) and water (WF2). The fractions were freeze-dried and evaluated for its antiinflammatory and antiulcer activity. Fractions NF1, CF1, BF2 and EF2 (20 mg/kg) showed significant antiinflammatory and antiulcer activity. The results obtained for antiulcer activity were also supported well by the histopathological examination of the open excised rat stomach. Further experiments are underway to determine which phytoconstituents are involved in antiinflammatory and antiulcer activities as well as mechanisms involved in gastroprotection.
ABSTRACT
Tridax procumbens L., Asteraceae, has been extensively used in Ayurvedic system of medicine for various ailments. Previous studies on the extracts of T. procumbens revealed remarkable immunomodulatory activity of TPEIF (T. procumbens ethanol insoluble fraction) extract. The dried methanol extract of T. procumbens was dissolved in distilled water, and then fractioned by re-extracting with chloroform, ethyl acetate and n-butanol subsequently. Immunomodulatory activities of these fractions were determined in vivo. The amounts of total phenolic compounds were also determined. Ethyl acetate and n-butanol fractions showed the significant immunomodulary activity. However, the ethyl acetate fraction exhibited the highest total phenolic content. Therefore, ethyl acetate fraction was subjected to further separation by chromatographic methods. Two phytochemicals SA-3 and SA-4 were obtained by repeated purification in sufficient amount to screen them for the immunomodulatory activity by the in vivo models i.e. neutrophil adhesion and delayed type hypersensitivity. In addition, the n-butanol fraction was subjected to silica gel column chromatography (CC); SA-6 was isolated from it. Mice were treated with two doses of SA-3, SA-4 and SA-6 (2 and 4 mg/kg) for fifteen days. Immune responses to T-dependent antigen SRBCs were observed using parameters like DTH and Neutrophil adhesion. Overall, SA-4 and SA-6 showed dose relative immunostimulatory effect on in vivo immune functions in mice. From these results, it can be suggested that these compounds may be used as potential immunostimulators. The structures of isolated phytochemicals were determined by UV, IR, NMR, and MS spectroscopic methods.