Chinese Bulletin of Botany ›› 2022, Vol. 57 ›› Issue (4): 444-456.DOI: 10.11983/CBB22088

• EXPERIMENTAL COMMUNICATIONS • Previous Articles     Next Articles

Antioxidant Activity of Tea Polysaccharide and Its Protective Mechanism Against Oxidative Damage

Zhang Mingzhu1, Qin Huaguang1, Mu Dan1, Yang Longyu1, Li Hu1, Qi Zehua1, Wang Yuxi1, Zhang Yongcheng1, Ye Lili1, Yin Wenjing2, Wang Shuyuan1, Rao Yuchun2,*(), Wu Yan1,*()   

  1. 1The Province Key Laboratory of the Biodiversity Study and Ecology Conservation in Southwest Anhui, School of Life Sciences, Anqing Normal University, Anqing 246133, China
    2School of Chemistry and Life Sciences, Zhejiang Normal University, Jinhua 321004, China
  • Received:2022-04-26 Revised:2022-06-28 Online:2022-07-01 Published:2022-07-14
  • Contact: Rao Yuchun,Wu Yan
  • About author:First author contact: These authors contributed equally to this paper

Abstract: Wan tea polysaccharides (WTPs) is a kind of acid glycoprotein extracted from tea, which has good antioxidant activity. The antioxidant activity of WTPs in Southwest Anhui was analyzed using the scavenging rate of free radicals as an index, and the repair effect of WTPs on free radical damage was further explored based on the exogenous ·OH injury cell model established by H2O2 and EDTA-Fe2+ and the endogenous hydroxyl radical injury model induced by PMA. The results showed that WTPs had good antioxidant activity against DPPH· and ·OH, with EC50 values of 209.5 and 535.2 µg∙mL-1 on scavenging efficiency, respectively, which was similar with Vc. The survival rate of cells in both exogenous and endogenous free radical oxidative damage models increased with the increase of WTPs concentration by cell proliferation assay, which could reach 87.41% and 85.84% when WTPs concentration was 800 µg∙mL-1, which was significantly higher than that in model group (47.67% and 48.03%). In terms of protective mechanism, laser confocal imaging of reactive oxygen species (ROS) distribution in cells and fluorescence intensity analysis showed that compared with the model group, WTPs had significant scavenging effect on exogenous and endogenous ROS in cell models, which was consistent with the results of antioxidant test in vitro. WTPs showed good free radical scavenging efficiency in vitro and its improvement effect on free radical damage at the cellular level. The study revealed antioxidant damage mechanism of WTPs in scavenging free radicals at the cellular level, which laid a foundation for further research on the anti-aging effect of tea polysaccharides on the body aging caused by free radicals.

Key words: tea polysaccharides, antioxidant, cell oxidative damage, repair mechanism