Phenolic Compounds as Cross-Links of Plant Derived Polysaccharides

Plant cell wall polysaccharides are partially cross-linked via phenolic compounds. As shown in the past, the most important phenolic compounds to cross-link plant cell-wall polysaccharides are ester-linked ferulic acid dimers, but p-coumarate dimers were also shown to be potential cross-linking compounds. Recently, ferulic acid dimers were identified and quantified in a range of cereal grains. The isolation of 8-O-4-dehydrodiferulic aciddi-arabinoside from maize bran shows that diferulic acids are able to form intermolecular cross-links between arabinoxylans. The more recently identified sinapic acid dehydrodimers and ferulic acid dehydrotrimers provide additional contributions to building up a strong network of plant cell wall polysaccharides.