24.03.2022

More than just stabilizers: Function and impact of plant mannans.

Catalin Voinuciuc has summarized the latest findings on plant mannans in a review published in New Phytologist. Some of these results derive from his own work, which he carried out most recently as head of the Junior Research Group on Designer Glycans at the IPB. Mannans consist of ß-1,4-linked mannose units and constitute polysaccharides of the hemicellulose fraction, which are essential components of the plant cell wall.

In his review, the author covers all important aspects, starting with occurrence and biosynthesis of mannans up to their expression in yeast, modification and application in industry and food production. A comprehensive chapter is devoted to the biological function of these polysaccharides and also to the role of mannan-modifying enzymes in this scenario. In addition to their general structure-building function as a component of the plant cell wall, mannans influence a variety of physiological processes. In the form of galactomannans, for example, they accumulate in the endosperm of Leguminose seeds where, similar to starch in cereals, they function as carbon stores feeding the embryo. In various associations with other sugars, heteromannans support processes such as seed development and germination, fruit ripening, heavy metal tolerance, pathogen defense, and abiotic stress tolerance of seeds. There are several indications that mannans provide the starting signal for the formation of new cell walls, thus acting at the forefront of all growth processes.

With regard to utilization, this group of substances becomes more and more important. As excellent dietary fibers with gelling properties, galacto- and glucomannans can be used as food additives and supplements for the dietary treatment of diabetes and other civilization diseases.

Original Publication:
Catalin Voiniciuc, Modern Mannan: A Hemicellulose's Journey. New Phytologist, doi: 10.1111/nph.18091