Isolation and structure elucidation of Eumitrin A₁ from lichen Usnea blepharea motyka and its cytotoxic activity

The purpose of this research was to isolate and elucidate structure of secondary metabolite compoundand to examine its cytotoxic activity of lichen Usnea blepharea Motyka obtained from Sulawesi – Indonesia. Powder of lichen was extracted using an acetone and continued separation by employing column chromatography (CC) with n-hexane and ethyl acetate solvents in a gradient elutionto produce a pure isolate. The structure was determined by UV-Vis, LC-MS, FTIR, ¹H-NMR, ¹³C-NMR, 2D-NMR (HMBC, HMQC, COSY). The UV-Visspectrophotometer measurement was obtained maximumwavelength of 229 nm and 334 nm. The LC-MS data of this compound showed a molecular weight of680. The ¹H-NMR, ¹³C-NMR with DEPT spectrums showedthat this compound has 34 carbon atoms consisting of 2 methyl groups, 2 methoxy groups, 1 methyl group, 6 metin groups, 3 methylene groups, and 20 C quartener atoms. The2D-NMR (HMBC, HMQC,COSY) spectrums of analysis could be inferred that this compound is a Eumitrin A₁ with the formula structure C34H32O15. The Eum itrin A₁ was examined its cytotoxic activityagainst Murine Leukemia P388 cells with IC₅₀4.5 μg/mL (very active).