Chemical constituents and cytotoxic activity of stem bark extract of Calophyllum inophyllum
Stem bark of Calophyllum inophyllum was extracted with aqueous methanol and screened for secondary metabolites. The crude extract was partitioned with n-hexane to remove fat-soluble constituents, thereafter a portion of the defatted extract was purified using silica gel column chromatography. Both the crude and defatted extracts were investigated for cyctotoxic activity using Brine shrimp lethality assay. A number of bioactive secondary metabolites were confirmed present in the crude while the chromatographic purification afforded three compounds that were characterized as stigmasta-5, 22-dien-3-O-β-D-glucoside (C-1), macluraxanthone (C-2A) and 1, 5-dihydroxyxanthone (C-2B). LC for both crude and defatted extract were 56.22 and 183.55 50 µg/mL, respectively, indicating a good cytotoxic potential.
Key words: Calophylum inophyllum; xanthones; secondary metabolites; Brine shrimps