Effects of chitooligosaccharide-functionalized graphene oxide on stability, simulated digestion, and antioxidant activity of blueberry anthocyanins

Abstract

In this study, we tested the in vitro efficacy of a graphene oxide-chitooligosaccharide (GO-COS) complex developed to protect blueberry anthocyanins (An) from degradation by various physicochemical factors and the digestive process. We prepared a GO-COS complex to adsorb An and protect them from the destructive effects of their ambient environment. The complex protected the An under various temperature, pH, light, oxidant, and reductant conditions. We evaluated An content and composition in a simulated digestive system using the pH differential method and the high performance liquid chromatography-mass spectrometry (HPLC-MS). The GO-COS carrier stabilized An in the intestine and protected their peroxyl radical-scavenging capacity. Additionally, we observed a dose-response relationship between An content and cellular antioxidant activity, and simultaneous improvement of An bioavailability when the An were encapsulated in the complex. The complex inhibited HepG2 cell proliferation at the tested dose range. This study provides valuable information for stability of An-rich products.

Keywords: Anthocyanins; Bioaccessibility; Cellular antioxidant activity assay; Graphene oxide/chitooligosaccharide; Protective effect; Simulated digestion.