PEP is the crude heteropolysaccharides isolated from Pleurotus eryngii.
PEP-1 and PEP-2 were purified from PEP by Cellulose DEAE-52 and Sephadex G-100.
High molecular mass PEP-2 exhibits more potent anticancer effect than PEP-1.
ROS was a critical mediator in PEP-2 induced HepG-2 cellular apoptosis.
PEP-2 is a good candidate for dietary supplement and therapeutic application in cancer.