Physicochemical properties and cellular protection against oxidation of degraded Konjac glucomannan prepared by γ-irradiation

- Irradiation in dosage of 100 kGy leads to excellent dispersibility in KGM.
- 100 kGy-KGM demonstrates excellent protective effect against oxidative damage.
- Possible mechanism for anti-oxidative activity in 100 kGy-KGM was analyzed.
- Irradiation was proven an effective method to improve properties of KGM.

Konjac glucomannan (KGM) is an important functional polysaccharide in food research. However, unstable dispersibility of KGM inhibits its in-depth study and wide application. In this study, a degraded KGM (100 kGy-KGM), which showed excellent dispersibility and specific physicochemical properties, were obtained by γ-irradiation in a dosage of 100 kGy. We investigated the protective effect of 100 kGy-KGM against H2O2 induced oxidative damage in LO2 cells. Our results demonstrated that pretreatment of LO2 cells with 100 kGy-KGM not only significantly increased cellular survivals and activities of GSH-Px and CAT, but also reduced levels of LDH, MDA and intracellular accumulation of ROS. The marked protective effect against oxidative damage and excellent dispersibility in 100 kGy-KGM allowed its possible use as an antioxidant. Our study provided fundamental knowledge to understand the structure-functions relationships of degraded-KGM, which could result in a theoretical guidance for the future application of KGM.