JUP and cancer: The IC50 value of Pg for HepG2 cancer cells, which was 8.75 μg/ml, equivalent to 27 μM, showed that purified Pg from S. marcescens EMS 5 strain did not have cytotoxic activity and had a weak inhibitory effect on the growth of HepG2 cancer cells (IC50>4 μg/mL).