Polysaccharides from Pleurotus eryngii: Selective extraction methodologies and their modulatory effects on THP-1 macrophages.

Polysaccharides from P. eryngii mushroom were selectively extracted using low-cost technologies (water at different conditions of temperature and pressure). Mannogalactan was the main polysaccharide in cold-water extracted fraction (CWEF), while a linear (1 -> 6)-beta-D-glucan was the main polymer in hot-water extracted fraction (HWEF). Autoclave-extracted fraction (AEF) contained a mixture of at least four different alpha and beta-glucans. The report of linear (1 -> 6)-beta-glucan and linear (1 -> 3)-beta-glucan is a new finding for P. eryngii fruiting bodies. The immunostimulatory properties of the fractions on THP-1 macrophages were studied. All fractions at 50, 250 and 500 mu g/mL were not cytotoxic and produced different stimulus on NO, IL-1 beta and IL-10 secretion by the cells. Thus, our results showed that it is possible to concentrate different P. eryngii polysaccharides in selected fractions using a simple and low-cost procedure. Since biological effects depends on the polysaccharide structure, this technique allows the obtainment of fractions with distinct immunomodulatory activities.