Polysaccharides from Auricularia auricula (AAP) were extracted by hot water extraction and fractionated by sequential precipitation with 10% and 80% (final concentration) ethanol into two fractions (named AAP-10 and AAP-80, respectively). Each fraction was further separated into three subfractions: AP-10-Ⅰ, AAP-10-Ⅱ, AAP-10-Ⅲ, AAP-80-Ⅰ, AAP-80-Ⅱ and AAP-80-Ⅲ. Each of the six polysaccharides was vacuum infiltrated into white radish before dehydration and rehydration. The effects of these polysaccharides on the rehydration characteristics of white radish were investigated by measuring the rehydration ratio, expansibility, water-holding capacity (WHC), color and texture parameters. Polysaccharides that greatly differed in their ability to improve the rehydration characteristics of dehydrated radish were selected for structural characterization. The results showed that compared with dehydrated radish without osmotic treatment, treatment with AAP could improve the rehydration characteristics of dehydrated radish in varying degrees. The effect of AAP-80-Ⅲ was most pronounced among the six polysaccharides. The rehydration ratio of radish treated with AAP-80-Ⅲ was 7.32, the expansibility was 3.22 mL/g, and the water-holding capacity was 87.2%; it had better color (L* value of 62.68 ± 0.17, a* value of −1.06 ± 0.02, and b* value of 4.23 ± 0.09), hardness (1746.14 ± 11.9) N and chewiness (1207.09 ± 9.39) N. AAP-10-Ⅰ could also improve the rehydration characteristics of dehydrated radish, but the difference was not significant. AAP-10-Ⅰ and AAP-80-Ⅲ contained neither protein nor nucleic acid, and both had hydrophilic functional groups. But the molecular mass of AAP-80-Ⅲ was less than that AAP-10-Ⅰ, and so AAP-80-Ⅲ could more easily penetrate into radish tissue. Moreover, arabinose accounted for a larger proportion in the monosaccharide composition of AAP-80-Ⅲ, which increased the water-holding capacity of radish tissue. Based on the above results, AAP-80-Ⅲ can effectively improve the rehydration characteristics of dehydrated radish.

This study aimed to investigate the protective effects and underlying mechanisms of malvidin-3-O-glucoside (Mv3G) on chlorpyrifos-induced damage of PC12 cells. The optimal dose of chlorpyrifos for inducing cell injury and the optimal dose of Mv3G for protecting against cell injury were determined. Western blot analysis was used to observe the changes in the expression of phosphoinositide 3-kinase/protein kinase B (PI3K/AKT) signaling pathway-related proteins, the autophagy-related protein Beclin1, and mammalian target of rapamycin (mTOR) following Mv3G treatment. The levels of the oxidative stress biomarker glutathione (GSH), the inflammatory cytokine tumor necrosis factor-α (TNF-α), acetylcholine esterase (AChE) activity, and the apoptosis-related protein cysteineaspartic protease-3 (Caspase-3) were measured using enzyme-linked immunosorbent assay. Based on cell viability and morphological changes, the optimal chlorpyrifos concentration was 30 µmol/L, and the optimal Mv3G concentration was 200 µmol/L. Experimental results demonstrated that Mv3G significantly improved the survival rate of chlorpyrifos-damaged PC12 cells, alleviated the inhibitory effect of chlorpyrifos on the PI3K/AKT signaling pathway, and increased GSH levels and AChE activity while reducing TNF-α levels and the expression of Beclin1 and Caspase-3. These findings indicate that Mv3G mitigates chlorpyrifos-induced oxidative stress, neuroinflammation, cholinergic dysfunction, apoptosis, and abnormal autophagy through the PI3K/AKT signaling pathway.