Arabinoxylans cross-linking

Figueroa-Espinoza, M.C., Morel, M.H., Surget, A., Rouau, X. 1999. Oxidative cross-linking of wheat arabinoxylans by manganese peroxidase. Comparison with laccase and horseradish peroxidase. Effect of cysteine and tyrosine gelation. J Sci Food Agric 79 460-463. 

Piber, M., Koehler, P. 2005. Identification of dehydro-ferulic acid-tyrosine in rye and wheat Evidence for a covalent cross-link between arabinoxylans and proteins. J Agric Food Chem 53 5276-5284. 

Boeriu CG, Oudgenoeg G, Spekking WT et al (2004) Horseradish peroxidase-catalyzed cross-linking of feruloylated arabinoxylans with a-casein. J Agric Food Chem 52 6633-6639... 

In contrast to the cell walls of parenchymatous tissues of dicotyledons, those of cereal grains (wheat, barley, etc.) contain very little, or no, pectic substances. The primary walls of most cereal grains have cellulose microfibrils, which are closely associated with glucomannan, and these fibrillar structures are embedded in an amorphous matrix of hemicelluloses, which consists mainly of arabinoxylans and/or P-D-glucans, some of which are cross-linked by phenolic esters and/or proteins (Selvendran,... 

Arabinoxylans (Figure 3B) have a backbone composed of 1,4-linked P-D-Xylp residues—some of the Xyl/ residues may be 0-acetylated [7]. Ara/ residues are linked to position C-2 and/or C-3 of the backbone. In primary walls P-d-GIc/jA or 4-0-Me p-D-Glc A residues are also attached to the xylan backbone and these polysaccharides are called glucuronarabinoxylans. The Ara/ side chains of arabi-noxylan and glucuronarabinoxylan may also contain ester-linked phenolic acids such as ferulic acid [9] that are potential sites for cross-linking by oxidative coupling (Figure 3B and C). 

Hartley, R.D., Morrison, W.H., 111, Himmelsbach, D.S., and Borneman, W.S., Cross-linking of cell wall phenolic arabinoxylans in graminaceous plants. Phytochemistry, 29, 3705,1990. 

Feruloylated arabinoxylans and arabinoxylan gels continue to be investigated and new sources and functional properties are being discovered. Several questions remained to be elucidated, especially those concerning the formation of higher ferulate cross-linking structures and their contributions to the gel development. FAXMB gels could be matrices suited for protein delivery in specific sites as the colon. Additional studies will also be required in order to understand the effect of different protein concentrations and the gel structure in the diffusion coefficient value. 

Figueroa-Espinoza, M. C. Rouau, X. (1998). Oxidative cross-linking of pentosans by a fungal laccase and a horseradish peroxidase mechanism of linkage between feruloylated arabinoxylans. Cereal Chemistry, 75, 259-265. 

Schooneveld-Bergmans, M. E. F., Dignum, M. J. W., Grabber, J. H., Beldman, G. Voragen, A. G. J. (1999). Studies on the oxidative cross-linking of feruloylated arabinoxylans from wheat flour and wheat bran. Carbohydrate Polymers, 38, 309-317. 

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