Antioxidant activities of novel galloyl phytosterols evaluated by human erythrocytes with the aid of confocal microscopy imaging

•Integrated use of biochemical and visual methods for investigation.•Morphology of erythrocytes unveiled a sensitive indicator for oxidative stress.•Excellent protective effects of the novel antioxidant on human erythrocytes. Notable protective effect of the novel galloyl phytosterol antioxidant on human erythrocytes was disclosed in this study. 2,2′-Azo-bis (2-amidinopropane) hydrochloride (AAPH) induced haemolysis of erythrocytes, and depletion of cellular glutathione were effectively inhibited by the galloyl phytosterol antioxidant. It was revealed that the level of glutathione was a more sensitive indicator than haemolysis for cellular oxidative stress. The morphology of erythrocytes obtained through laser scanning confocal microscopy (LSCM) imaging provided structural details for haemolysis and glutathione investigation and was more sensitive than the level of glutathione. The liposome model exhibited that the novel antioxidant preferred to anchor in the membrane and had better performance for membrane protection than gallic acid. The strategy of integrated use of biochemical and visual methods developed in this study is valuable for investigation on mechanistic behaviours of antioxidants.