Evaluation of the immunomodulatory activity of bioproducts obtained from the edible-medicinal mushroom Pleurotus ostreatus

Edible mushrooms are an important source for obtaining novel substances of nutritional and biopharmaceutical interest. In this regard, in Cuba, the consumption of mushrooms of the genus Pleurotus spp. has been promoted as part of the Urban Agriculture Program. Taking advantage of its availability and considering previous reports on their content of compounds with potential application, in this work, there was investigated the immunomodulatory and immunonutrition properties of biopreparations from this mushroom. New methodologies were developed to generate biopreparations from the mycelium and fruiting bodies of Pleurotus ostreatus. The obtained bioproducts were generated by biomass aqueous extraction and/or drying, which led to the registration of the NutriSetas® tradename. The bioproducts contained mainly carbohydrates (including ß-glucans) and proteins, among other secondary metabolites with potential biological activity. They showed M1-polarizing effects on macrophage populations, and the aqueous fraction obtained from the mycelium by submerged fermentation was able to stimulate the complement system alternative pathway. Noteworthy, the aqueous extract displayed radioprotective effects on the hematopoietic and immunological parameters when administered in a mice biomodel of ionizing radiation-induced secondary immunodeficiency. Similar immunostimulatory effects, either in the humoral or cellular immune responses, were found with dry and powdered preparations from fruiting bodies. Their immunonutritional effect in an experimental model of protein-energetic malnutrition in Balb/c mice evidenced nutritional recovery and immunological improvement status. This provided the first report of such an effect for edible mushroom preparations. This work received the Annual Award of the Cuban Academy of Sciences for the year 2017. Los hongos comestibles son una fuente importante para la obtención de nuevas sustancias de interés nutricional y biofarmacéutico. En Cuba se ha promovido el consumo de hongos del género Pleurotus spp. como parte del Programa de Agricultura Urbana. En este trabajo se investigó las propiedades inmunomoduladoras e inmunonutricionales de preparaciones de este hongo, dada su disponibilidad y los informes previos sobre su contenido de compuestos con potencial aplicación para estos fines. Se establecieron nuevas metodologías para obtener biopreparaciones a partir del micelio y de los cuerpos fructíferos de Pleurotus spp., mediante la extracción a