| Summary: | The development of new physiologically functional ingredients allows us to expand the range of these additives and to attract additional non-traditional sources of raw materials. Prebiotics are non-digestible food ingredients that stimulate the growth of probiotic microorganisms in the gastro-intestinal tract. The chemical nature of the most prebiotics are carbohydrates nature polymers: dietary fibers and nondigestible oligosaccharides. Among non-starch polysaccharides, arabinoxylan (AX), arabinogalactan (AG), and β-glucan are of paramount importance. Arabinoxylans are mainly found in cereals grains, for example, wheat, rye, barley, oat, rice, and sorghum. The current study is a review of literature and authors' own research on biosynthesis, chemical structure, production, physicochemical and physiological properties of arabinoxylans. The structure and molecular weight of AX are vital determinants of their physicochemical, technological and physiological properties. In the article is illustrated in detail the biosynthesis of arabinoxylan in a plant tissue, which makes it possible to understand the formation mechanism of complex structure of these polysaccharides. The main part of cereal grains arabinoxylans are contained mainly in the cell walls of starchy endosperm and the aleurone layer, in the bran tissues, and in the husk of some cereals. The amount of arabinoxylans in a particular tissue depends on the genus and species. However, the degree of branching was found to be lower in arabinoxylans from aleurone than in that from original bran. The molecular structure of arabinoxylans from wheat, rye, and barley is less complex than that from rice, sorghum, finger millet, and maize bran, since their side branches contain, besides the arabinose residues, small amounts of xylopyranose, galactopyranose, and α-Dglucuronic acid or 4-O-methyl-α-D-glucuronic residues. In the review analyzed methods of obtaining water-soluble and water-unsoluble AX from different agricultural by-products. Water-soluble AX were extracted with a high-temperature treatment combined with followed enzymatic starch removal. After the hot water extraction, non-soluble fibers and protein fractions were separated and the washed fiber fraction was further treated with alkali (NaOH) solution with different solid to liquid ratios. Also there are described the technological properties of AX that were obtained from different cereals. During the enzymatic hydrolysis of AX are formed arabinoxylanoligosaccharides (AXOS), consisting of arabinoxylooligosaccharides and xylooligosaccharides (XOS). This process is a base of the production of prebiotic arabinoxylooligosaccharides from cereals and cereal by-products. This review mainly focuses on the perspectives of using the arabinoxylans as a raw material for obtaining oligosaccharides-prebiotics.
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