Thaumatococcus daniellii leaves: its chemical compositions, antioxidant and antimicrobial activities.
The preliminary phytochemical investigation of n-hexane, ethyl acetate and methanol extracts of Thaumatococcus daniellii leaves revealed the presence of fats and oils, terpenoids, flavonoids, steroids and glycosides. The antimicrobial tests against some strains of bacteria and fungi showed inhibitions at moderate to high concentrations. Methanol extract of the plant exhibited low 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity with IC50 of 615.14 μg/ml. Gas chromatography-mass spectrometry (GC-MS) characterization of n-hexane, ethylacetate and methanol extracts of T. daniellii leaves identified , thirteen and fifteen compounds, with tetracontane (28.76%) and L-ascorbic acid (15.07%); hexadecanoic acid (21.62%) and γ-sitosterol (11.06%); and naphthalene-1,2,3,5,6,7,8,8a-octahydro-1,8a-dimethyl-7-(1-methylethenyl)-,1R(1.alpha.,7.beta.,8a.alpha.] (26.90%) and hexadecanoic acid (12.60%) being the major compounds respectively. The GC-MS analysis revealed various peaks of bioactive compounds of which the antioxidant and antimicrobial activities of the plant have been attributed to the prominent compounds in synergy with all the other compounds present in smaller quantities in the extracts.
Keywords: Thaumatococcus daniellii, Antimicrobial activity, Antioxidant activity, GC-MS analysis, L-ascorbic acid, γ-sitosterol