Comparison of Antioxidant Activities of Three Kinds of Juices and Their Protective Effects on Oxidative Damage of Colon Cell NCM460

To compare the contents of active ingredients and antioxidant activity of Rosa roxburghii Tratt juice (RRTJ), pomegranate juice (PJ) and blueberry juice (BJ) and investigate the protective effects of three kinds of fruit juices against dextran sulfate sodium (DSS)-induced oxidative damage in human normal colonic epithelial cells NCM460. There were 28 bioactive components in the three juices. The total polyphenols and total flavonoids of RRTJ were significantly higher than those in the PJ and BJ (P<0.05), 22.77 and 12.04 mg/mL, respectively. Meanwhile, the ABTS⁺· and DPPH· scavenging abilities of the juice were significantly higher than those in the PJ and BJ (P<0.05), and the half scavenging rate (IC₅₀) was 4.00±0.32 and 10.03±0.51 μL/mL, respectively. Pearson correlation analysis indicated that the total polyphenol content of the juice was positively correlated with the ABTS⁺· scavenging ability (P<0.05). In addition, RRTJ had the strongest ability to alleviate DSS-induced oxidative damage in NCM460 cells, and 2 μL/mL RRTJ could restore the viability of oxidatively damaged NCM460 cells to a level comparable to the control and reduce the level of reactive oxygen species (ROS) in DSS-induced cells. The results showed that the content of total polyphenols in fruit juice was positively correlated with antioxidant capacity. The content of total polyphenols in juice was positively correlated with antioxidant capacity, and the antioxidant activity and the ability to alleviate DSS-induced oxidative damage in NCM460 cells were the strongest in vitro, which had the potential for in-depth research and development.