Antioxidant Properties of Water-Soluble Gum from Flaxseed Hulls.

Key Findings

This paper assessed extraction techniques for soluble flaxseed gum (SFG) (mucilage) which is mainly present in the outermost layer of the seed hull and can be released by soaking in water other examples. In this study, SFG was extracted from hulls and its antioxidant properties were evaluated. SFG showed similar functional groups when compared to gum arabic, which suggested a polysaccharidic structure. Using different antioxidant systems, the antioxidant capacity of SFG showed DPPH radical-scavenging capacity, strong ABTS radical scavenging, high reducing power capacity and potent β-carotene bleaching inhibition activity.

Abstract

Soluble flaxseed gum (SFG) was extracted from flax (Linum usitatissimum) hulls using hot water, and its functional groups and antioxidant properties were investigated using infrared spectroscopy and different antioxidant assays (2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid (ABTS), reducing power capacity, and β-carotene bleaching inhibition assay), respectively. The antioxidant capacity of SFG showed interesting DPPH radical-scavenging capacity (IC50 SFG = 2.5 mg·mL(-1)), strong ABTS radical scavenging activity (% inhibition ABTS = 75.6% ± 2.6% at 40 mg·mL(-1)), high reducing power capacity (RPSFG = 5 mg·mL(-1)), and potent β-carotene bleaching inhibition activity (IC50 SFG = 10 mg·mL(-1)). All of the obtained results demonstrate the promising potential use of SFG in numerous industrial applications, and a way to valorize flaxseed hulls.