[Study on mechanism of enhancing antioxidant activity in fermented Ziziphi Spinosae Semen with Poria cocos].

In this study, the antioxidant property changes in fermented Ziziphi Spinosae Semen(FZSS) with Poria cocos were analyzed by DPPH, ABTS and FRAP methods. Then the content determination of active ingredients and ~1H nuclear magnetic resonance(~1H-NMR) spectroscopy were also used to investigate the mechanism of FZSS with P. cocos in enhancing the antioxidant activity. The results showed that the content of active ingredients such as total phenols, total saponins and total polysaccharides were significantly increased during the fermentation time. The results of ~1H-NMR metabonomics showed that the contents of amino acids such as leucine, lysine, valine and alanine, nitrogen compounds such as creatine, creatinine, and betaine, and secondary metabolites, for instance, jujuboside A and spinosin were higher after fermentation, and above components showed positive correlation with antioxidant capacity in Pearson correlation analysis. Therefore, it was inferred that the enhancement of antioxidant activity of FZSS may be the result of the joint action of various chemical components. This study preliminarily clarified the mechanism of FZSS in enhancing the antioxidant activity, and provided new research ideas for the product development and utilization of FZSS.