Bioassay guided fractionations, isolation and evaluation of compounds of Melia dubia fruits for Anti-inflammatory activity

Abstract

Melia dubia  (synonym: Melia azedarach, Indian lilac)  belongs to family Meliaceae. In the present study dried coarsely powdered fruits (5.0 kg) was extracted successively with Petroleum ether, chloroform, ethanol and methanol as extracting solvents by using soxhlet apparatus and finally marc was macerated with water for two days with occasional agitation to obtain aqueous extract. Aqueous extract of fruit was subjected to gradient column chromatography by using glass column (3x60cm). Silica gel (60-120) used as stationary phase while mobile phase used as  methanol (100%), methanol/water (9:1), methanol/water (1:1) and water (100%) yielded fractions as FR-I (7.42%), FR-II (18.35%), FR-III (16.57%) and FR-IV (14.23%) respectively, which were evaluation for anti-inflammatory activity by using  in-vivo carrageenan induced  rat paw edema method and by in-vitro protein denaturation and membrane stabilization method using indomethacine as reference standard drug. FR- III was found most bioactive fraction. Further it was subjected to gradient polyamide column chromatography it gives compounds Salanin, Melianone, Compositolide, 3-α-Tigloymelianol and Compositin. Structure of isolated compounds were elucidated with the help of IR, NMR and Mass spectroscopy techniques and by comparisons with reported spectral data

        In today era the most common complaint of patient is pain and inflammation, which arise due to the injury caused by chemicals, physical shock or microbiological agents. Therefore need to search safer anti- inflammatory compounds from natural sources. Among the isolated compounds salanin & compositin showed a more potent anti-inflammatory. This is the first study of evaluating anti-inflammatory by bioassay guided fractionation procedure and led to the isolation of two bioactive compounds. Therefore this study gives rational support to the traditional uses of M. dubia fruits in inflammatory disorders.