Methylation and 2D NMR analysis of arabinoxylan from the seeds of Plantago asiatica L.

► Polysaccharide (PLP-3) from the seeds of Plantago asiatica L. was highly branched arabinoxylan, containing glucuronic acid. ► PLP-3 had β-1,4-linked Xylp backbone, branching at its O-2 (17.87%) or O-3 (24.24%) positions. ► The main terminal residues were T-linked Xylp, T-linked Araf and T-linked GlcAp.