Statistical optimization of fermentation conditions for metabolites production by <i>Lentinus edodes</i> and investigation of anticancer activity

A statistical method was utilized in this study to enhance <i>Lentinus edodes</i> (shiitake) secondary metabolites, thereby improving its anticancer properties. The importance of employing the statistical method in this study stemmed from the initial statistical optimization of the substrate in submerged conditions, and the subsequent transfer of that optimal setting to the solid-state culture medium. The Plackett-Burman (PB) screening indicated that wheat starch, meat peptone, and vitamin B₆ had a more pronounced impacted on polysaccharide production. The optimal substrates for polysaccharide production, identified using response surface methodology (RSM) after screening, was revealed to contain 48.56 g/L wheat starch, 15 g/L meat peptone, and 300 µg B₆ vitamins. Shiitake polysaccharide solutions exhibited shear-thinning behavior, enhanced viscosity, and gel-like properties at higher concentrations. Shiitake polysaccharide also demonstrated superior emulsifying capacity for oil-in-water emulsions, suggesting its potential as an effective stabilizer in food formulations. The fruit body of shiitake had the highest diversity in flavonoids and phenolic acids and anticancer activity against MDA-MB-231 breast cancer cell. The IC50 levels of extracted polysaccharide, fruiting body, fruit stipe, fruit pileus, mycelium from the control sample, and mycelium cultivated in MgO nanoparticles-enriched culture medium were 225, 182, 194, 244, 202, and 138 μg/mL, respectively. The statistical methods used in this study have successfully optimized the bioactive compound content in both the biomass and fruiting body of shiitake, yielding a promising natural source of polysaccharides and anticancer agents.