Antioxidant and cytoprotective effects of enzyme-extracted constituents of Protaetia brevitarsis seulensis powder

This study was aimed to compare the antioxidant and cytoprotective effects of hot-water and enzyme-extracted constituents of Protaetia brevitarsis seulensis powder. The products of enzymatic extraction had 1,1-diphenyl-2-picrylhydrazyl (DPPH)-radical-scavenging activity, cytotoxic effects, and provided cytoprotection against H₂O₂ and intracellular reactive oxygen species. Enzymatic extraction improved DPPH-radical-scavenging activity relative to hot-water extraction (P < 0.05), with inhibition rates of 33% at 500 μg/mL and 35% at 1000 μg/mL. Cell viability ranged from 100 to 122%, and was higher for hot-water than for enzymatic extraction (P > 0.05). Hot-water extraction achieved greater cytoprotection against H₂O₂ than enzymatic extraction. However, enzymatic extraction achieved greater antioxidant and cytoprotective activity against reactive oxygen species than hot-water extraction. These results provide evidence of the antioxidant and cytoprotective effects produced by enzymatic extraction of the active ingredients from Protaetia brevitarsis seulensis powder.