Screening Antitumor Compounds Psoralen and Isopsoralen from Psoralea corylifolia L. Seeds

Figure 1

Anticancer effect of fractions I, II, III, and IV on KB and K562 cell lines. The cells were incubated with vincristine sulfate (VCR) or doxorubicin hydrochloride (Dox) or other test compounds for 48 h. Incubation with DMSO alone as control and the final concentration of DMSO in the medium never exceeded 0.1%. After 48 h, the MTT assay was performed to measure cell inhibition rate. Results were reported as mean (n = 4) percent of untreated control with error bars showing the standard deviation. Asterisks indicate significant cytotoxicity relative to the positive control (*P < .05, **P < .01).