Structural characterization, functional properties, bioactivity and oral absorption characterstics of Oudemansiella...

The medicinal fungus Oudemansiella raphanipies (O. raphanipies) attracts significant interest for its broad-spectrum bioactivities, with its polysaccharide demonstrating particularly notable pharmacological properties. This study systematically investigated the extraction, physicochemical properties, structural, functional traits, biological activities, and oral absorption of O. raphanipies polysaccharide. Response surface methodology optimized the extraction condition of O. raphanipie polysaccharides by UAE method, achieving a yield of 210.35 ± 0.20 mg/g (55 °C, 90 min, 250 W, 1: 60 g/mL). The purified O. raphanipie polysaccharide (UAE-ORP) (568.57 kDa), an α-pyranose mainly composed of glucose (35.48%) and galactose (28.51%), showed high thermal stability (322 °C). In addition, UAE-ORP showed interesting water retention capacity and oil retention capacity, and good foaming and emulsion properties. UAE-ORP demonstrated potent antioxidant activity, with DPPH scavenging rate reaching 90.43% and hydroxyl radical scavenging rate at 57.13%, significant inhibition of BSA denaturation (97.49%) and NO secretion, and potential prebiotic effects. UAE-ORP was significantly distributed in the gastrointestinal tract based on NIR imaging result, retaining in intestines for 24 h, indicating its potential as a prebiotic agent. Thus, UAE-ORP is a promising functional food additive with integrated advantages.