Isolation and characterization of Stigmasta-7, 22-dien-3-ol (α-Spinasterol) from Entada africana stem bark crude extract

Abstract

The phytochemical  investigation of the stem bark extracts of Entada africana led to the isolation and characterization of Stigmasta-7,22-dien-3-ol from the dichloromethane soluble portion of acetone/methanol (1:1v/v) crude extract. The powdered stem bark sample of Entada africana was defatted with hexane and extracted with acetone/methanol (1:1v/v) mixture. The dichloromethane soluble fraction was purified on a low pressure column containing silica gel 60 (60-200 mesh). The purification afforded an isolate coded Enac3 (85 mg) with Rf value of 0.404 in hexane/ethyl acetate (4:1). The isolate was characterized using IR, NMR data and in comparison with literature. Analysis of spectroscopic data and literature comparison suggests Enac3 as stigmasta-7, 22-dien-3-ol. The isolation of stigmasta-7, 22-dien-3-ol from the stem bark of Entada africana suggests the presence of useful bioactive principles which could be exploited for medicinal purposes.