Isolation and Purification of Lycium Barbarum Polysaccharide and Its Antioxidant Mechanism on HepG2 Cells Damaged by H₂O₂

OBJECTIVE  To extract and purify Lycium barbarum polysaccharide(LBP) from Qaidam Basin, preliminary analysis of its chemical structure composition, and study of the antioxidant mechanism of LBP by cellular experiments.

METHODS  LBP was extracted by ultrasound-assisted method and purified by DEAE-52 cellulose column. Their structures were analyzed by high performance gel permeation chromatography, Fourier transform infrared spectroscopy and ion chromatography. Preliminary in vitro antioxidant evaluation of LBP was conducted using four methods: DPPH, ABTs, FRAP, and CUPRAC. Evaluate the antioxidant activity of LBP using H₂O₂ induced HepG2 cell model.

RESULTS  A total of three LBP fractions were obtained: LBP-C1, LBP-C2 and LBP-C3. Structural analysis revealed that three types of LBP had different molecular weights, functional groups, and monosaccharides. In vitro antioxidant studies had shown that LBP-C1 had the best antioxidant potential. Cell experiments had found that LBP-C1 could alleviate the oxidative stress state of HepG2 cells by regulating the Nrf2/HO-1 pathway.

CONCLUSION  LBP-C1, a polysaccharide of LBP, has high antioxidant potential, which can be applied to the subsequent research of antioxidant function medicine or food development.