抄録
Atranorin, lichexanthone, and the (+)-usnic, diffractaic, divaricatic, perlatolic, psoromic, protocetraric, and norstictic acids isolated from the lichens Parmotrema dilatatum (Vain.) Hale, Usnea subcavata Motyka, Usnea sp., Ramalina sp., Cladina confusa (Sant.) Folmm. & Ahti, Dirinaria aspera Häsänen, and Parmotrema lichexanthonicum Eliasaro & Adler were evaluated against UACC-62 and B16-F10 melanoma cells and 3T3 normal cells. SRB assay revealed significant cytotoxic activity in protocetraric, divaricatic, and perlatolic acids on UACC-62 cells (GI50 0.52, 2.7, and 3.3 μg/mL, respectively). Divaricatic and perlatolic acids proved the most active on B16-F10 cells (GI50 4.4 and 18.0 μg/mL, respectively) and the most cytotoxic to 3T3 normal cells. Diffractaic, usnic, norstictic, and psoromic acids were cytotoxic to UACC-62 cells in the 24.7 to 36.6 μg/mL range, as were protocetraric and diffractaic acids to B16-F10 cells (GI50 24.0 and 25.4 μg/mL, respectively). Protocetraric acid was highly selective (SI* 93.3) against UACC-62 cells, followed by norstictic, perlatolic, psoromic, and divaricatic acids, while norstictic and divaricatic acids were more selective against B16-F10 cells. The high SI* value obtained for protocetraric acid on UACC-62 cells makes it a potential candidate for the study of melanomas in experimental models. Chemometric analysis was performed to evaluate the general behavior of the compounds against the cell lines tested.
