Synthesis of selenized dextran using the non-thermal effects of pulsed electric field: Structure features, antioxidant and anti-glycation activities

Chemically selenized polysaccharides, as a new type of selenium supplement, have attracted widespread attention in recent years. However, the low selenization efficiency resulting from traditional heating methods has been limiting the application of selenized polysaccharides. Herein, we selected the reaction system of dextran (DEX) and Na 2 SeO 3 /HNO 3 /BaCl 2 as a model to investigate the effect of pulsed electric fields (PEF) on the selenization of dextran. Results showed that the non-thermal effect of PEF contributed to the high 79.5 % loading of selenium. Compared with the simulated controlled heating treatment (SHT, simulating the temperature rise generated by PEF) and the normal heating treatment (NHT), the antioxidant activity and anti-glycation activity of the selenized dextran (SeDEX) prepared by PEF were higher, but PEF did not alter the selenium sites. In all samples, selenite ions reacted with the C6 hydroxyl group of DEX to form selenate esters. In conclusion, PEF significantly improved the selenization efficiency of DEX through its non-thermal effects (mainly polarization effects) and has potential applications in other chemically selenized polysaccharides.