Sulfated Cardamine Hupingshanensis Polysaccharides Structure Elucidation,Bioactivity Study And Its Application

Objective :In order to explore the structural modification of Cardamine hupingshanensis polysaccharides(CHP)and the changes of the biological activity of the modified polysaccharide,the sulfated structure of CHP was modified by the sulfur trioxide-pyridine method,and after the successful modification,it was separated and purified by column chromatography,and the main structure was studied by nuclear magnetic resonance and other techniques.The main structure was investigated by NMR.And a food packaging material with antioxidant function was produced by compounding with Zein.The main research process is as follows: firstly,we obtained five different substitution degrees of sulfated Cardamine hupingshanensis polysaccharides(SCHP)by sulfation modification,the substitution degrees were 0.46,0.55,0.69,0.72 and 0.80,respectively.the modification effect was initially analyzed by Fourier transform infrared spectroscopy.On this basis,the water solubility and antioxidant activity of SCHP were investigated.After further purification,we obtained two different polysaccharides,and we named the main part of them as SCHP-II.The structure of SCHP-II was analyzed by GPC and NMR co-contrast techniques and the biological activity was also studied.Finally,we successfully prepared new bioactive films using SCHP compounded with Zein and performed functional and characterization studies on the films.Experimental results: We obtained that SCHP-?is mainly composed of glucose and galactose,and the Mw of SCHP-?is 22.2 k Da;Mn is 13.4 k Da.Meanwhile,the main chain structure is?4)-?-D-Glc(1?4)-?-D-Galp A-(1?4)-?-D-Galp A-(1?4)-?-Rhap(1?6)-?-DGlc(1?.We also found that the in vitro antioxidant results showed that SCHP has better antioxidant activity and water solubility than CHP.This indicates that the sulfated modified CHP has better application prospects.The scavenging ability of the films against hydroxyl radicals,ABTS,and DPPH was improved after the addition of different concentrations of SCHP.The films with the addition of 4 mg/ml SCHP showed some improvement in tensile strength,although lower in transparency,compared to the films without the addition of SCHP.These results suggest that Zein-SCHP film can be used as a food packaging material with antioxidant function.