Antioxidant properties of feruloyl glycerol derivatives

The natural plant components, 1-feruloyl-sn-glycerol (FG) and 1,3-diferuloyl-sn-glycerol (F2G), were synthesized by the enzymatic esterification of glycerol and soybean oil mono- and diacylglycerols, respectively, with ethyl ferulate. The isolated FG and F2G were examined for their antioxidant activities as free radical scavengers (DPPH assay) and peroxyl lipid oxidation inhibitors (TBARS assay). The H atom transfer kinetics, as monitored by DPPH free radical bleaching, of FG showed that the mono-feruloyl glycerol acted as a rapid antioxidant (50% reduction of DPPH radical < 5 min) in ethanol solutions while F2G and ferulic acid activity rates were in the range of intermediate antioxidants (50% reduction of DPPH radical in 5–30 min). FG and F2G showed similar activity as the control agent, ethyl ferulate, towards the inhibition of the AAPH-induced peroxyl radical oxidation of surfactant emulsified γ-linolenic acid. A slight excess of feruloyl groups was sufficient to completely suppress the formation of secondary lipid oxidation products.

► Mono- and diferuloyl-sn-glycerol are natural antioxidants.
► Free radical antioxidant capacity determined by DPPH assay.
► Monoferuloyl-sn-glycerol showed better antioxidant capacity.
► Peroxyl lipid oxidation inhibition antioxidant capacity determined by TBARS assay.
► Slight excess of feruloyl groups lowered formation of lipid oxidation products.