Plant fructans: Recent advances in metabolism, evolution aspects and applications for human health

Abstract

Fructans, fructose polymers, are one of the three major reserve carbohydrate in plants. The nutritional and therapeutic benefits of natural fructans in plants have attracted increasing interest by consumers and food industry. In the course of evolution, many plants have developed the ability of regulating plant fructans metabolism to produce fructans with different structures and chain lengths, which are strongly correlated with their survival in harsh environments. Exploring these evolution-related genes in fructans biosynthesis and de novo domestication of fructans-rich plants based on genome editing is a viable and promising approach to improve human dietary quality and reduce the risk of chronic disease. These advances will greatly facilitate breeding and production of tailor-made fructans as a healthy food ingredient from wild plants such as huangjing (Polygonatum cyrtonema). The purpose of this review is to broaden our knowledge on plant fructans biosynthesis, evolution and benefits to human health.

Keywords: Evolution aspects; Fructosyltransferases; Functional foods; Metabolism; Plant fructans.

Graphical abstract

Fig. 1

Representative species containing different fructans structure.

Fig. 2

Schematic representative structure of plant fructans.

Fig. 3

Evolutionary and phylogenetic analysis of invertase genes in plant and algal species. The amino acid sequence of invertases that have been experimental verification was used as database sequences; Query sequence in Table S1 were selected by the criteria of E-value<10⁻¹⁰ using BLASTP. The sequences were aligned with MAFFT (https://mafft.cbrc.jp/alignment/software/) and the phylogenies constructed with the RAxML-HPC2 on XSEDE (http://www.phylo.org/). Ectocarpus siliculosus was used as the outgroup (the species are shaded) and the root of the tree, and the Interactive Tree of Life resource (http://www.itol.embl.de) was used to draw the phylogenetic tree.

Fig. 4

The health benefits of plant fructans.