Fig. 1

Effects of Rhododendron leaf extracts on IEC6 (a) and HaCaT (b) cells incubated with three different concentrations (5, 50, and 500 μg/mL) of leaf extracts as indicated. Cell viability and proliferation was analyzed by the MTT assay upon incubation at 37 °C for 24 h. The percentage of MTT reduction for each extract concentration was normalized to that of the 0.5 % DMSO solvent. Values are given as mean ± standard deviations from three independent experiments, each performed in triplicates. Statistical evaluation was performed by one way ANOVA-analysis; levels of significance are indicated as *for p < 0.05