Antitumor activity of sulfated extracellular polysaccharides of Ganoderma lucidum from the submerged fermentation broth

Water-soluble extracellular polysaccharides are known to possess weak or no in vitro antitumor activity. In this experiment, a mixture of extracellular Ganoderma lucidum polysaccharides (GLP) from the submerged fermentation broth was sulfated and studied on their antitumor activity. The sulfated GLP performed significant inhibition on the proliferation of assayed carcinoma cells in a dose-dependent manner, and present a degree of substitution-dependent suppressing to HepG2 cells. Meanwhile, the sulfated GLP presented remarkable but not dose-dependent inhibition on Heps hepatona in mice. With same degree of substitution, the sulfation protocol with aminosulfonic acid–pyridine yielded GLP sulfates with higher activity on HepG2 cells. In comparison, the native GLP showed no or little antitumor activity on the assayed cell lines but remarkable inhibition on suppressing the proliferation of rat Heps. The highest in vivo inhibition rate of 55.5% provided by sulfated GLP was observed on suppressing the proliferation of rat Heps.