Exo and endopolysaccharides production from Pleurotus ostreatus cultivated in medium containing fruit wastes

Studies have demonstrated the potential for utilizing agro-industrial byproducts for Pleurotus spp. Extracts containing polysaccharides from mushrooms obtained through solid culture, as well as from mycelial biomass obtained through liquid culture (endopolysaccharides), can regulate the immune response and increase resistance to disease. Additionally, exopolysaccharide extracts obtained from culture broth can regulate the immune response. This study aimed to utilize food industry waste to produce mycelial biomass and exopolysaccharides from Pleurotus ostreatus grown in media containing apple, grape, lemon, and orange peels. P. ostreatus produced mycelial biomass in all four residues, with the highest concentration (4.91 g L-1) in grape peels. Together with lemon and orange peels, it also produced higher concentrations of exopolysaccharides (3.22 to 3.95 g L-1). The exo- and endo-polysaccharides obtained from the culture broth and the mycelial biomass cultivated with grape peels, respectively, had α-D-glucose, α-D-galactose, α-D-xylose, and galacturonic acid as their main constituents.