Preliminary physicochemical evaluations and bioactive properties of column fractions from the lichen

The chloroform-soluble portion of an ethanolic extract of the lichen Ramalina farinacea was separated by column chromatography using n-hexane: ethylacetate (4:1) as the mobile phase and silica gel S as the stationary phase. Four column fractions (B, C, H and I) and the n-hexane-soluble portion of the ethanolic extract (N) were screened for possible biological activity by the Brine Shrimp Lethality Bioassay Technique. Some physicochemical evaluations of the column fractions such as pH determinations, ultraviolet (UV) absorption spectra, solubility profile and some chemical tests were also carried out. Phytochemical and elemental analysis of the crude lichen material was equally carried out. Results showed that all the fractions and the n-hexane extract were biologically active with the bioactivity of N > B > C > I > H. Fractions B and C were both acidic and evaluation of their solubility profile, UV spectra and some chemical reactions suggest that the fractions are possibly depsides and depsidones respectively.