Structural characterization of lignin: a potential source of antioxidants guaiacol and 4-vinylguaiacol.

•The isolated lignin was a ρ-hydroxyphenyl-guaiacyl-syringyl lignin and S/G of 0.35.•The major units in the lignin macromolecule are derived from hydroxycinnamic acids.•The antioxidant activity of the lignin was due to the ferulic acid subunits.•The lignin is a desirable source of antioxidants guaiacol and 4-vinylguaiacol.