Antioxidant Activity of Flaxseed (Linum usitatissimum L.) shell and Analysis of Its Polyphenol Contents by LC-MS/MS

Flaxseed (Linum usitatissimum L.) is important source of oil and protein for industrial, pharmaceutical, and nutritional applications. In order to estimate the effects of lyophilized aqueous extract of flaxseed shell (AEF) and evaporated ethanolic extract of flaxseed shell (EEF), we studied their DPPH, ABTS, DMPD and O(2)(center dot-)scavenging effects. Total antioxidant activity by ferric thiocyanate method, Fe3+, Cu2+ and [Fe3+-(TPTZ)(2)](3+) reducing ability, and Fe2+ chelating activity. Also, alpha-tocopherol, BHA, trolox, and BHT were used as positive controls. The results clearly AEF and EEF demonstrated effective antioxidant activity. The quantity of p-hydroxybenzoic, vanillin, p-coumaric acid, ascorbic acid, ferulic acid, and ellagic acid were investigated by LC-MS/MS. The present study will introduce a novelty for further studies on the antioxidant effects of AEF and EEF.