The Anticancer, Anti-inflammatory, and Antioxidant Activities of Protein-Bound and Protein-free Polysaccharides Isolated from Pleurotus Ostreatus

This study investigates the multifaceted bioactivities of protein-bound and protein-free polysaccharides extracted from Pleurotus ostreatus (PO). Firstly, distinct differences in the ultraviolet-visible (UV-Vis) spectra between protein-bound polysaccharides (PbPOP) and protein-free polysaccharides (PfPOP) were observed, particularly at 280 nanometers (nm), highlighting the presence or absence of protein content. Subsequently, the antioxidant potential of both forms of polysaccharides was explored using DPPH and ABTS radical scavenging assays. The DPPH assay revealed significant scavenging activity with IC50 values of 9.09 μg/ml for protein-bound POP and 8.25 μg/ml for protein-free POP. The ABTS assay further demonstrated the antioxidant capacity, with IC50 values of 297.0 μg/mL for protein-bound POP and 150.4 μg/mL for protein-free POP, compared to 17.38 μg/mL for ascorbic acid. Moreover, the anticancer activity of these polysaccharides was assessed using the MTT assay, demonstrating dose-dependent cell viability enhancement, with protein-free POP exhibiting superior efficacy (IC50 = 306.4 μg/mL) compared to protein-bound POP (IC50 = 329.4 μg/mL). Additionally, the inhibition of COX-1 and COX-2 by aspirin, PbPOP, and PfPOP was evaluated, with PfPOP showing the highest inhibition percentages (46% for COX-1 and 58% for COX-2). This comprehensive investigation underscores the promising therapeutic potential of polysaccharides from Pleurotus ostreatus as versatile agents against cancer, inflammation, and oxidative stress-related conditions.