Evaluation of antioxidant, anti-inflammatory, analgesic and antipyretic activities of the stem bark of Sapindus mukorossi

BACKGROUND Saponins are the main constituents of genus Sapindus and have the therapeutic potential for inflammatory disorders. In this study the antioxidant, anti-inflammatory, analgesic and antipyretic potential of the stem bark of soap nut (Sapindus mukorossi) methanol extract and its derived fractions has been investigated. METHODS Powder of stem bark of the S. mukorossi was extracted with methanol (SMM) and fractionated in order of n-hexane (SMH), chloroform (SMC), ethyl acetate (SME), n-butanol (SMB) and the remaining as aqueous fraction (SMA). Quantitative estimation for the total phenolic and total flavonoid content was carried out in all the extract/fractions. Further, various in vitro antioxidant assays were also performed. Anti-inflammatory (Carrageenan induced paw edema), analgesic (hot plate latency test) and antipyretic (rectal temperature) were determined in Sprague-Dawley rat. RESULTS Quantitative estimation of total phenolic contents in extract/fractions varied between 252.3 ± 2.41 mg of GAE/g - 594.16 ± 4.3 mg of GAE/g while the total flavonoids estimated were from 11.02 ± 1.3 mg of RUE/g to 96.9 ± 3.2 mg of RUE/g. Standard antioxidant assays such as scavenging of DPPH, hydroxyl radical, nitric oxide, phosphomolybdenum assay, reducing power, inhibition of β-carotene bleaching, iron chelation activity and inhibition of heat induced protein denaturation indicated the antioxidant potential of the extract/fractions. Carrageenan induced paw edema of rat was effectively inhibited by SMA at 300 mg/kg administration to rat (84.19 ± 1.48%) after 3 h and analgesia (latency time) in hot plate test (55.78 ± 1.22%) after 120 min. SMA at 300 mg/kg distinctly decreased the rectal temperature in brewer's yeast (Saccharomyces cerevisiae) induced pyrexia in rat. CONCLUSION The resulted obtained in this study suggested the therapeutic importance of stem bark of S. mukorossi in inflammatory related disorders.