Identification of Some Chemical Constituents of the Leaves of Alstonia boonei and Bridelia ferruginea

Abstract

This study aims to investigate the phytochemical composition of the leaves of Alstonia boonei and Bridelia ferruginea. The leaves of the two plants were extracted successively with n-hexane and ethyl acetate, concentrated and fractionated over gravity silica gel column chromatography. Some fractions obtained were analyzed using gas chromatography mass spectroscopy (GC-MS).  GC-MS results indicated that the main constituents of the fractions from Alstonia boonei were fatty acid methyl esters, while the main constituents of the fractions from Bridelia ferruginea were fatty acid esters (47.46%) and triterpenoids (43.39%). Each of the fractions has at least one exclusive tetracyclic or pentacyclic triterpenoid present. Friedelan-3-one and clionasterol were present in the Alstonia boonei fractions, while beta-amyrin, lup-20(29)-en-3-one, lupeol, alpha-amyrin acetate and 4,4,6a,6b,8a,11,11,14b-octamethyl-1,4,4a,5,6,6a,6b,7,8,8a,9,10,11,12,12a,14,14a,-octadecahydro-2H-picen-3-one were present in the B. ferruginea fraction. Obviously, B. ferruginea is a reservoir to many pentacyclic triterpenoids. The pentacyclic triterpenoids may be used as a biomarker in the chemo taxonomical classification of the plants whilst acting as relevant contributors to the acclaimed biological benefits of B. ferruginea reported in traditional medical practices. The leaves of the two plants contain many bioactive compounds which may find application in pharmaceutical formulations as well as nutraceuticals and bio-pesticides preparations