Comparison of the protective effect of black and white mulberry against ethyl carbamate-induced cytotoxicity and oxidative damage

Increasing evidence indicates that crude extracts derived from mulberry confer protection against oxidative stress. However, the antioxidant capacity of mulberry extract among different cultivars remains elusive. The main objective of the present study was therefore to investigate the effect of black mulberry extract (BMB) and white mulberry extract (WMB) on ethyl carbamate (EC)-induced cytotoxicity and oxidative stress. This study showed that the contents of total phenolics, total flavonoids, total procyanidins, cyanidin-3-O-glucoside, cyanidin-3-O-rutinoside and pelargonidin-3-O-glucoside of BMB were higher than that of WMB. Moreover, our results showed that phenolics-abundant BMB was stronger than WMB in scavenging ABTS and DPPH free radicals. BMB was more effective in ameliorating EC-induced cytotoxicity by inhibiting excessive ROS generation, suppressing mitochondrial dysfunction and increasing GSH concentration in HepG2 cells than WMB. Taken together, our study revealed that BMB afforded better protection against EC-caused cytotoxicity than WMB.