Preparation, characterization and antioxidant activity evaluation in vitro of Fritillaria ussuriensis polysaccharide-zinc complex

The emphasis of this study lies in that we present a novel fluorescence scanning approach to evaluate the antioxidant capacity of Fritillaria ussuriensis polysaccharide-zinc (FUP-Zn) complex. FUP was extracted successfully, and the corresponding FUP-Zn complexes with different substitution degrees were obtained after modified chemically with ZnCl2. The physiochemical characteristics of the as-prepared samples were determined by ultraviolet-visible spectroscopy, infrared spectroscopy, X-ray powder diffraction, scanning electron microscope, energy dispersive spectrum, thermo gravimetric-differential thermal analyses and etc., and these characterization results confirmed the successful synthesis of FUP-Zn complexes with good stability. The scavenging ability investigation of FUP-Zn complexes towards hydroxyl radicals and superoxide anion radicals carried out by us has revealed that the integration of FUP and Zn greatly enhanced the antioxidant activity due to the synergistic effect and larger pore size of FUP-Zn complexes, and the antioxidant activity of FUP-Zn complex with different substitution degrees is heavily dependent on the amount of Zn. This study indeed provides vital theoretical basis for the promising antioxidant and zinc supplement evaluation from more novel polysaccharide-zinc complexes with suited Zn amount.