A comparative study on the structures of Grifola frondosa polysaccharides obtained by different decolourization methods and their in vitro antioxidant activities. Issue 10 (30th September 2019)

• Record Type: Journal Article
• Authors: Zhang, Yu; Chen, Zehong; Huang, Zi; Wu, Zhijing; Xu, Jingya; Wang, Kaiping
• Is Part Of: Food & function. Volume 10:Issue 10(2019)
• Page Start: 6720
• Page End: 6731
• Publication Date: 2019-09-30
• Subjects: Food -- Analysis -- Periodicals; Food -- Composition -- Periodicals; Nutrition -- Periodicals; 664.07
• DOI: 10.1039/c9fo01511f
• Languages: English
• ISSNs: 2042-6496

Abstract

Abstract : Grifola frondosa polysaccharides with different structures were obtained by two decolorization methods, and their antioxidant structure–activity relationship in vitro was discussed. Abstract : Decolourization of polysaccharides is one of the crucial procedures that affects their structure, which is closely related to their bioactivity. Here, Grifola frondosa polysaccharide (GFP) was decolourized with H2 O2 and AB-8 macroporous resin. Then, two main fractions, named DGFP and SGFP, were obtained by purification with Sepharose CL-4B. The molecular weights of these two polysaccharides were determined to be 6.306 × 10 6 (±0.410%) Da and 1.174 × 10 7 (±0.299%) Da by HPSEC. Monosaccharide analysis indicated that DGFP was composed of glucose, mannose, and galactose (32.20 : 1.00 : 1.75), while SGFP consisted entirely of glucose. Despite a backbone →4)-α-Glcp-(1→ in two polysaccharides, reducing ends Rα →3)-α-Glcp and Rβ →4)-β-Glcp were observed in DGFP by 1D/2D NMR. The results suggested that decolourization with low concentrations of H2 O2 might alter the structure of GFP and generate new reducing ends. In vitro antioxidant results implied that DGFP exhibited a higher ability to scavenge DPPH and hydroxyl radicals and reduced the over-generated ROS levels in a concentration-dependent manner. These results suggested that the antioxidant effects of GFP could be activated by decolourization with H2 O2 . Therefore, DGFP might be a more promising natural antioxidant than SGFP.