While numerous bioactive polysaccharides have been identified from mushrooms, their mechanisms of action, particularly through the induction of oxidative stress in tumor cells, remain underexplored. This study isolates a novel polysaccharide, LSPS2, derived from Laetiporus sulphureus, followed by the elucidation of its distinctive structural features and specific antitumor activity in A549 lung carcinoma cells. LSPS2 was composed primarily of glucose (88.1%) and minor amounts of mannose (8.0%) and galactose (3.9%). Methylation and one-dimensional/two-dimensional nuclear magnetic resonance (1D/2D NMR) analysis results indicated that LSPS2 was composed of (1→3)-linked-D-β-glucopyran residues and (1→4)-linked-D-α-glucopyran residues as the main chain. The side chains were connected to O-6 and O-3 of glucopyranose (Glcp) residues with terminal Glcp. It differs from previous reports on L. sulphureus polysaccharides. Functionally, LSPS2 markedly suppressed A549 cell viability in a manner that depended on both exposure duration and concentration. LSPS2 upregulated malondialdehyde (MDA) and downregulated reduced glutathione (GSH), demonstrating that LSPS2 induces oxidative stress in A549 cells. The results of superoxide dismutase (SOD) activity assays further indicated that LSPS2 downregulates SOD activity, which may be the mechanism by which LSPS2 induces oxidative stress and, consequently, apoptosis in A549 cells. This targeted downregulation of a key antioxidant enzyme highlights a potential pathway for polysaccharide-induced tumor cell death. Our findings not only identify LSPS2 as a structurally distinct biopolymer but also elucidate its mode of action, underscoring its prospective application in tumor therapy and functional foods, warranting further investigation.

This study explores an innovative approach based on deep eutectic solvent (DES)-synergistic ultrasonic-assisted extraction (UAE) of anthocyanins from blueberry pomace (BP). Choline chloride–lactic acid (ChCl-LA, 1:2) was identified as the most efficient DES and provided the highest anthocyanin recovery. The optimal conditions for ChCl-LA-synergistic UAE (ChCl-LA-UAE) were obtained as follows: ultrasonic power of 270 W, extraction time of 30 min, liquid-to-solid ratio of 35:1, and water content in ChCl-LA of 40%, achieving a total anthocyanin content (TAC) of 3.5168 mg/g, with R² = 0.9860. This value was significantly higher than those obtained with 70% ethanol (3.1962 mg/g) and pure water (1.9137 mg/g). SEM images revealed that ChCl-LA-UAE disrupted the surface structure of the samples, thereby promoting anthocyanin release. COSMO-RS simulations confirmed that ChCl-LA significantly enhanced the interaction between the solvent and the representative anthocyanin (cyanidin-3-O-glucoside, C3G), resulting in higher extraction efficiency. In vitro antioxidant assays further demonstrated that the synergistic system exhibited stronger antioxidant activity. Overall, ultrasonic-synergistic DES extraction could be an eco-friendly method for recovering high-value compounds from blueberry and its byproducts.

Blueberry anthocyanins (BAs) exhibit strong antioxidant and lipid-regulating activities; however, their chemical instability and low oral bioavailability limit their practical application. In this study, two plant-based bilayer nanocarriers were developed using soybean lecithin as the lipid core and gum arabic (GA) or carrageenan (CGN) as the shell polysaccharide. The optimized systems achieved encapsulation efficiencies of 79.7% and 81.9%, respectively. Structural analyses showed that anthocyanins were stably incorporated into the carriers through multiple non-covalent interactions and transformed from a crystalline to an amorphous state. The two shell polysaccharides exhibited distinct conformation-dependent protective behaviors: GA provided better thermal protection, whereas CGN showed superior resistance to light, metal ions, ascorbic acid, and simulated intestinal digestion. After INFOGEST digestion, anthocyanin retention in the intestinal phase was 47% and 51% for the GA- and CGN-coated systems, respectively, and antioxidant activity was better preserved than in the free anthocyanin group. In an oleic-acid-induced HepG2 lipid accumulation model, the CGN carrier showed good biocompatibility and significantly enhanced the lipid-lowering effect of anthocyanins, with the most pronounced reduction in intracellular triglycerides. These results indicate that the CGN carrier has considerable potential for maintaining anthocyanin stability, modulating digestive behavior, and enhancing biological efficacy, and provide a reference for the design of plant-based delivery systems for bioactive ingredients.