Acute stressor alters inter-species microbial competition for resistant starch-supplemented medium.

Gut microbiome community dynamics are maintained by complex microbe-microbe and microbe-host interactions, which can be disturbed by stress. studies on the dynamics and manipulation of those interactions are costly and slow, but can be accelerated using fermentation. Herein, fermentation was used to determine how an acute stressor, a sudden change in diet, impacts inter-bacterial species competition for resistant starch-supplemented medium (RSM). Fermentation vessels were seeded with fecal samples collected from 10 individuals consuming a habitual diet or U.S. military rations for 21 days. . growth in response to RSM was attenuated following ration consumption, whereas growth of was enhanced. These differences were not evident in the pre-fermentation samples. Findings demonstrate how incorporating fermentation into clinical studies can increase understanding of stress-induced changes in nutrient-microbiome dynamics, and suggest that sudden changes in diet may impact inter-species competition for substrates.