The waxy mutation in sorghum and other cereal grains reshapes the gut microbiome by reducing levels of multiple beneficial species

Authors

Qinnan Yang, University of Nebraska-Lincoln
Mallory J. Suhr Van Haute, University of Nebraska-LincolnFollow
Scott E. Sattler, USDA-Agricultural Research Service, University of Nebraska - LincolnFollow
Devin J. Rose, University of Nebraska-LincolnFollow
Anthony Juritsch, University of Nebraska-LincolnFollow
Jing Shao, University of Nebraska
Kristin A. Beede, University of Nebraska LincolnFollow
Robert J. Schmaltz, University of Nebraska - LincolnFollow
Jeff Price, University of Nebraska-LincolnFollow
John Toy, USDA-Agricultural Research Service, University of Nebraska-LincolnFollow
Amanda E. Ramer-Tait, University of Nebraska - LincolnFollow
Andrew K. Benson, University of Nebraska - LincolnFollow

Document Type

Article

Date of this Version

2-2-2023

Citation

GUT MICROBES 2023, VOL. 15, NO. 1, 2178799 https://doi.org/10.1080/19490976.2023.2178799

Comments

Open access.

Abstract

Waxy starches from cereal grains contain >90% amylopectin due to naturally occurring mutations that block amylose biosynthesis. Waxy starches have unique organoleptic characteristics (e.g. sticky rice) as well as desirable physicochemical properties for food processing. Using isogenic pairs of wild type sorghum lines and their waxy derivatives, we studied the effects of waxy starches in the whole grain context on the human gut microbiome. In vitro fermentations with human stool microbiomes show that beneficial taxonomic and metabolic signatures driven by grain from wild type parental lines are lost in fermentations of grain from the waxy derivatives and the beneficial signatures can be restored by addition of resistant starch. These undesirable effects are conserved in fermentations of waxy maize, wheat, rice and millet. We also demonstrate that humanized gnotobiotic mice fed low fiber diets supplemented with 20% grain from isogenic pairs of waxy vs. wild type parental sorghum have significant differences in microbiome composition and show increased weight gain. We conclude that the benefits of waxy starches on food functionality can have unintended tradeoff effects on the gut microbiome and host physiology that could be particularly relevant in human populations consuming large amounts of waxy grains.