PRODUCTION AND CHARACTERIZATION OF BIOMASS AND EXOPOLYSACCHARIDES FROM THE EDIBLE MUSHROOM LENTINUS SQUARROSULUS

Abstract

This study investigated the production and characterization of fungal biomass and
exopolysaccharides (EPS) from the indigenous edible wild-type mushroom Lentinus squarrosulus (L.
squarrosulus) grown in submerged fermentation. This mushroom is widely consumed in rural
communities but remains underexplored for industrial development of bioproducts. Two nutrient media, Potato dextrose broth (PDB) and Yeast extract broth (YEB) were used for cultivation over 21 days. The biomass yield, EPS concentration and pH changes were measured at intervals of 3 days. The highest EPS (0.46 ± 0.01 mg/mL) and biomass (6.83 ± 0.043 mg/mL) production was achieved on day 9 in PDB compared to lesser production with YEB. The nature of EPS was determined by Fourier-transform infrared (FT-IR) spectroscopy that indicated the presence of characteristic functional groups of polysaccharide β-glycosidic bonds. Functional analysis revealed high water solubility (54.55 ± 0.80%) and water absorbing capacity (91.40 ± 1.20%), antioxidant assay showed highly active radical scavenging properties (87.41 ± 1.05% equivalent to 0.415 ± 0.004 mg/mL gallic acid). Protein and carbohydrate profiles indicated that EPS was predominantly carbohydrate (62.26 ± 0.16%). These results show that EPS from L. squarrosulus possess favourable structural and bioactive attributes that strongly support its potential use in food-based applications.