Size Matters: Influence of Particle Size on Antioxidant, β-Glucan, and Anti-Inflammatory Potential in Pleurotus floridanus (Agaricomycetes).

Cellular damage resulting from elevated levels of free radicals can lead to persistent health issues. Pleurotus floridanus, an edible white oyster mushroom, is rich in β-glucans with potent antioxidant and anti-inflammatory properties. In this research, we examined the β-glucan content, total phenolic content, as well as antioxidant and anti-inflammatory potential of hot water extracts with varying particle sizes (< 75, 75-154, 154-300, and 300-600 μm) of both whole and sliced fruiting bodies of P. floridanus. The findings revealed that the в-glucan content increased as the particle size increased, although no significant differences were observed. Conversely, smaller particle sizes (< 75 μm) of whole and sliced fruiting bodies of P. floridanus exhibited higher phenolic content, 2,2-diphenyl-1-picryl-hy-drazyl (DPPH) and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) scavenging activity, and reducing ability compared with larger particle size (> 75 μm). Of the four samples (AW2, AW3, AS1, and AS2) with the highest antioxidant activity selected for anti-inflammatory assays, all demonstrated the ability to reduce nitric oxide and tumor necrosis factor-alpha levels, but did not enhance interleukin-10 expression in lipopolysaccharide-stimulated RAW264.7 cells. Interestingly, particle size < 75 to 300 μm did not appear to influence the anti-inflammatory activity, because no significant differences were observed among the particle sizes. Therefore, a particle size < 300 μm in a P. floridanus hot water extract could serve as a valuable source of antioxidant and anti-inflammatory compounds to counteract the harmful effects of free radicals.