Enhancing the Antioxidant Activity of Technical Lignins by Combining Solvent Fractionation and Ionic-Liquid Treatment.

ABSTRACT: A grass soda technical lignin (PB1000) underwent a process combining solvent fractionation and treatment with an ionic liquid (IL), and a comprehensive investigation of the structural modifications was performed by using high-performance size-exclusion chromatography, ³¹ P NMR spectroscopy, thioacidolysis, and GC-MS. Three fractions with distinct reactivity were recovered from successive ethyl acetate (EA), butanone, and methanol extractions. In parallel, a fraction deprived of EA extractives was obtained. The samples were treated with methyl imidazolium bromide ([HMIM]Br) by using either conventional heating or microwave irradiation. The treatment allowed us to solubilize 28 % of the EA-insoluble fraction and yielded additional free phenols in all the fractions, as a consequenc

SUBMITTER: Majira A 

PROVIDER: S-EPMC6899661 | biostudies-literature | 2019 Nov

REPOSITORIES: biostudies-literature