Affiliation
a North-Caucasus Federal University, Stavropol, Russian Federation
b Северо-Кавказский федеральный университет, Ставрополь
Copyright ©Ryabtseva et al. This is an open access article distributed under the terms of the Creative Commons Attribution 4.0. (
http://creativecommons.org/licenses/by/4.0/), allowing third parties to copy and redistribute the material in any medium or format and to remix, transform, and build upon the material for any purpose, even commercially, provided the original work is properly cited and states its license.
Abstract
Galacto-oligosaccharides are known for their prebiotic activity. They are obtained from lactose using bacterial or fungal betagalactosidases. This article describes the factors that affect the biosynthesis and purification of galacto-oligosaccharides using Kluyveromyces yeasts, as well as summarizes some prospective research areas in this sphere.
The research covered ten years of scientific publications on the production of galacto-oligosaccharides with yeast beta-galactosidases. The review pool included 87 articles published in peer-reviewed journals and registered in Scopus, Web of Science, PubMed, and eLIBRARY.RU.
The yield, composition, and properties of galacto-oligosaccharides depend on the enzyme, its application, biosynthesis optimization, and purification conditions. Beta-galactosidases from Kluyveromyces can simultaneously catalyze hydrolysis and transgalactosylation reactions. The biosynthesis conditions vary a lot across the review pool, as does the yield of galacto-oligosaccharides, which usually remains below 30–40% while the total lactose conversion reaches 80–90%. Kluyveromyces beta-galactosidases can be used as whole-cell enzymes in immobilized form or together with other enzymes. They improve the economic indicators of biosynthesis, and / or the yield and / or the structure of galacto-oligosaccharides. If synthesized directly in milk or whey, galacto-oligosaccharides may yield new functional dairy products and additives. The method of selective bioconversion with Kluyveromyces yeast brings the purity of galacto-oligosaccharides up to 90% in an economical and sustainable way.
Eventually, galacto-oligosaccharides can be obtained from dairy by-products. Other promising areas include the enzymic mixes of different producers, as well as a comprehensive use of Kluyveromyces beta-galactosidases for galacto-oligosaccharide biosynthesis and purification.
Keywords
Lactose,
beta-galactosidases,
Kluyveromyces,
transgalactosylation,
hydrolysis,
whey,
purification
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