Abstract:The enzymatic properties and oxidative cross-linking properties of black wheat flour pentosan（WEP）were studied.Xylanase was used to hydrolyze WEP，and the viscosity of pentosan solution was measured under different enzyme dosage and reaction time.And the viscosity of pentosan solution was also measured under different oxidation systems of hydrogen peroxide/peroxidase （H2O2/POX），glucose/glucose oxidase/peroxidase （Glc/GOX/POX）and FeCl3 chemical oxidation system，thus to confirm the optimum concentration of the oxidant reagent.The results showed that with the increase of the amount of xylanase content，the rate of pentosan hydrolysis increased.When the dosage of enzyme was 10 mg/g substrate，the specific viscosity of WEP solution reduced 72%after enzymatic hydrolysis for 120 minutes.When the dosage of enzyme was 1 mg/g，the rate of enzymatic hydrolysis also increased with increase of reaction time.The specific viscosity of WEP reduced 45% after the reaction of 240 minutes.Oxidative cross-linking characteristics study found that pentosan could be oxidized cross-linked in different degrees under three oxidation systems.Under the most suitable conditions，the degree of oxidative cross-linking of FeCl3 was the largest，with a specific viscosity increase of 108.2 %，followed by GLC/GOx/POX system and H2O2/POX system，with 51.5 % and 34.8 % respectively.The enzymatic properties and oxidative cross-linking properties of pentosan from black-grain wheat flour could be used to change its viscosity to increase its applicability.