Validation of the Chemical Constituents of Crude Leaf Extract of Datura discolor with Qualitative Phytochemical Screening and GC-MS Analysis

Abstract

This study sought to investigate into the crude extract of the leaves of Datura discolor Bernh. with a view to validate the chemical constituents of the leaves. Extraction was achieved via maceration using methanol and solvent was removed after filtration by evaporation to dryness in the open. Preliminary phytochemical screening of the crude extract was qualitatively performed using standard operating procedures used by renowned scholars. Gas chromatography tandem mass spectrometry (GC-MS) was used to further elucidate the secondary metabolites present in the leaves of the plant. Phytochemicals detected are alkaloids, steroids, terpenoids, glycosides, saponins, phenolic compounds, tannins and lipids. Major active secondary metabolites identified via GC-MS are cis-9-Octadecenoic acid (29.59%), hexadecanoic acid (19.72%), octadecanoic acid (7.56%), 1,2-epoxyhexadecane (6.35%), methyl hexadecanoate (6.22%), methyl-11-octadecenoate (5.57%), methyl-15-tetracosenoate (4.16%), and tetradecanoic acid (3.50%). Other compounds which are present in traces with percentage abundance less than 3 % include 3,7,11,15-tetramethyl-2-hexadecen-1-ol; methyl-trans,trans--9,12-octadecadienoate; trans-13-docosenoic acid; 2,6,10,18,22-tetracosahexaene; methyl octadecanoate; dodecyl hexyl oxalate; 2-Methyl-2-(3-methyl-1-vinyl-2-butenyl)oxirane; methyl tetradecanoate; and 2-methyl-3-methylene-2-(4-methyl-3-pentenyl)bicyclo[2.2.1]heptane. These results affirms that Datura discolor Bernh, is rich in secondary metabolites which have diverse pharmacological activities with fatty acids and their esters being the most abundant constituents.