Cell viability (%) of WRL-68 and HepG2 cells exposed to different concentrations of Con-PAC, MW-PAC, and EGCG measured by MTS cell viability assay. WRL-68 and HepG2 cells were exposed to 10–1000 µg/mL concentrations of Con-PAC (A and B, respectively), MW-PAC (C and D, respectively), and EGCG (E and F, respectively) for 24 h. Cell viability of the WRL-68 and HepG2 cells was measured by incubating (3 h at 37 °C) the cells with MTS cell viability reagent. Results presented are means ± SD of three independent experiments. Means sharing the same letter are not significantly different at the 5% level. Con-PAC: PACs extracted by conventional method; MW-PAC: PACs extracted by microwave-assisted method; EGCG, epigallocatechin gallate.