Biofortification of dietary fibre: exploring enhanced β-glucan and arabinoxylan content in a panel of Triticum and wild relatives

TL;DR

This study explores how wild wheat relatives can be used to improve the dietary fiber content of wheat, which is important for human health.

Contribution

The study identifies wild wheat relatives with higher β-glucan and arabinoxylan content, offering new opportunities for wheat biofortification.

Findings

Wild relatives like Aegilops peregrina and Aegilops kotschyi have higher β-glucan and arabinoxylan than modern wheat.

β-glucan correlates positively with protein but negatively with starch and grain weight.

Wild genetic resources show untapped potential for improving wheat's nutritional quality.

Abstract

Dietary fibres, especially non-starch polysaccharides including β-glucan and arabinoxylan from cereal grains, are vital for human health due to their role in lowering cholesterol, regulating glycaemic index, and reducing the risk of chronic diseases like type II diabetes. A daily intake containing 2% or more β-glucan is often associated with health benefits. Wheat (Triticum aestivum L.), a staple crop and major source of dietary carbohydrates, contains limited variability for these fibre components compared with its wild relatives. To explore genetic resources for fibre biofortification, we evaluated a panel of 478 wheat genotypes including 37 wild relatives, 6 tetraploid, and 435 hexaploid wheat accessions for β-glucan, arabinoxylan, alongside protein, and starch content. The panel showed wide variation, with mean values of 0.93% for β-glucan, 5.77% for arabinoxylan, 13.37% for protein, and 68.51% for starch. Among wild relatives, Aegilops peregrina and Aegilops kotschyi emerged as superior sources of high β-glucan and arabinoxylan, whereas modern cultivars generally exhibited lower values. Significant positive correlations were observed between β-glucan and protein, and negative associations with starch and thousand-grain weight, indicating potential trade-offs in grain composition. These findings highlight the untapped potential of wild genetic resources for enhancing the nutritional quality of wheat and provide promising candidates for pre-breeding and biofortification strategies aimed at improving dietary fibre in staple foods.

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