Effects of media change on cell recovery. (A) 3TC-L1 cells were treated with PPC, SD, Lipobean® at 0.1 mg/ml. (B) CCD-25Sk cells were treated with PPC, SD, Lipobean® at 1 mg/ml. After 24 h, the media was removed and then was changed with fresh media. The cell viability was measured by MTT assay after 72-96 h incubation in fresh media. The data represent the mean ± S.D. of triplicate assays expressed as percentages of the control. Each experiment was repeated independently at least twice, and the representative results are shown. + P < 0.05, * P < 0.01 compared to 24 h treated each group.