Comparison of the antitumor activity of polysaccharides extracted by boiling water and enzyme assistance from Ganoderma lucidum

Polysaccharides are the most important pharmacologically active constituents of Ganoderma lucidum. In this work, polysaccharides were extracted from Ganoderma lucidum with boiling water method and enzyme assisted method. The human liver hepatocellular carcinoma cell line HepG2 was used to compare the an- titumor effect of the two kinds of extraction with 3-（4, 5-dimethylthiazol-2-yl）-2,5-diphenyltetrazolium bromide （MTT） test. Both of these two kinds of Ganoderma lucidum polysaccharides reduced cell viability of cancer cell HepG2 in a dose and time-dependent manner. At low concentrations, there was no significant difference in the effectiveness of L 1 and L2; while at concentrations over 0.8 ug/mL, the difference in the effectiveness of L2 in comparison to L1 became significant. At the concentrations of 3.2 ug/mL, the cancer cells were almost killed in 2 d.