Phytochemical Investigation of some Nigeria Solanum Species for Steroidal Alkaloids
A comprehensive review of the literature on the genus Solanum is presented. Ten Solanum species growing in Nigeria were screened for the presence of steroidal alkaloids generally and Solasodine in particular in all their morphologial parts. Of oil the Solanum species that gave positive results for the presence of alkaloid, S. americanum Mill (unripe fruits) was found to give Lou highest, yield (4.2) of total alkaloids followed by the unripe fruits of S.nigrum L. (4.0%). The lowest yield of alkaloid was given by S.americanum root, (0.1). These estimates were determined gravimetrically. Of the morphologial parts tested, nine were found to contain Solasodine based on TLC analysis. Of the morphologial parts that contained solasodine were fruits, while two were stems and one was a leaf. Solasodine was not detected in any of the roots tested. Solasodine was isolated from the unripe fruits of S. erianthum by column chromatography using neutral alumina and its structure was confirmed by direct comparison with authentic solasodine (m.p., mmp, TLC, Co-TLC and i.r.). In addition, a steroid GLycosldE solamargine and a steroidal sapogenin: diosgenin were detected in the unripe fruits of S.erianthum.