Effect of Saccharomyces cerevisiae CICC 32883 Fermentation on the Structural Features and Antioxidant Protection Effect of Chinese Yam Polysaccharide

In this study, Chinese yam polysaccharide (CYP) was fermented by Saccharomyces cerevisiae CICC 32883, and its structural features and antioxidant activities before and after fermentation were analyzed. S. cerevisiae CICC 32883-fermented CYP (CYP-SC) had higher carbohydrate content and lower protein content than the nonfermented CYP (CYP-NF). The monosaccharide composition of CYP-SC was unaffected, but the proportion was changed. Compared with CYP-NF's molecular weight and polydispersity of 124.774 kDa and 6.58, respectively, those of CYP-SC were reduced to 20.384 kDa and 3.379. Antioxidant results showed that CYP-SC had better effects than CYP-NF in scavenging DPPH, ABTS, hydroxyl, and superoxide radicals. Moreover, CYP-SC showed better activities in enhancing oxidation capacity and protecting HepG2 cells than CYP-NF. Furthermore, the effects of CYP-SC on alleviating and repairing H2O2-damaged HepG2 cells are superior to those of CYP-NF. This work offers a green and efficient method for enhancing the antioxidant activity of dietary plant polysaccharides.