Preparation of Lentinula edodes polysaccharide-calcium complex and its immunoactivity

Polysaccharide is a major bioactive component of mushrooms. In this study, for the first time, starting from a new Lentinula edodes polysaccharide L2, we prepared a novel L2-calcium complex and the process was optimized. Scanning electron microscopy and Fourier Transform infrared spectrometry were used for characterization. The immunostimulating activities of L2 and L2-calcium complex were measured by enhancing the production of two cytokines TNF-alpha and IL-6 in RAW264.7 cells. While L2-calcium complex significantly stimulates the secretions of TNF-alpha and IL-6 compared with the control, complex with calcium ion decreased the secretion of them. These facts indicate that calcium ion can modulate immune stimulating activity of Lentinula edodes polysaccharide L2.