Co-fermentation of wheat bran and wheat starch process water with Lactobacillus paracasei EG9 produced a postbiotic-rich functional ingredient (FWB) that alleviated constipation in a loperamide-induced mouse model through a dual-action mechanism of directly supplying bioactive metabolites and indirectly reprogramming the gut microbiota.
Key Findings
Results
Fermentation of wheat by-products with Lactobacillus paracasei EG9 significantly enhanced the nutritional profile of the substrate, enriching it with short-chain fatty acids (SCFAs) and functional macromolecules while improving physicochemical properties.
Wheat bran and wheat starch process water were used as co-fermentation substrates with Lactobacillus paracasei EG9
The fermentation process produced a postbiotic-rich functional ingredient designated FWB
Enrichment included both SCFAs and functional macromolecules
Physicochemical properties of the substrate were improved through fermentation
Results
FWB intervention alleviated constipation symptoms in loperamide-induced constipated mice in a distinct, non-linear, dose-dependent manner.
A loperamide-induced constipation mouse model was used for in vivo evaluation
The dose-response relationship was described as 'non-linear' and 'dose-dependent'
An optimal dose was identified that produced the most significant therapeutic effects
Constipation symptoms were measurably alleviated at the optimal dose
Results
FWB at the optimal dose significantly accelerated gastrointestinal motility in constipated mice.
Gastrointestinal motility was a key outcome measure in the constipation mouse model
Acceleration of motility was observed at the optimal FWB dose
Effect was part of the broader alleviation of constipation symptoms
The effect was dose-dependent with a non-linear response curve
Results
FWB intervention mitigated systemic inflammation in the loperamide-induced constipation mouse model.
Systemic inflammation was assessed as part of the in vivo evaluation
Mitigation of inflammation was observed at the optimal FWB dose
Inflammatory effects were considered part of the mechanistic therapeutic action of FWB
This effect was identified alongside gastrointestinal motility improvement and colonic mucosal repair
Results
FWB facilitated colonic mucosal repair in constipated mice.
Colonic mucosal repair was evaluated as an outcome in the constipation model
Mucosal repair was facilitated at the optimal FWB dose
This finding suggests a structural restorative effect in addition to functional motility benefits
Colonic mucosal repair was identified as one of three major therapeutic effects alongside motility improvement and inflammation reduction
Results
FWB exerted therapeutic effects through a dual-action mechanism: directly supplying bioactive metabolites and indirectly reprogramming the gut microbiota.
Direct action involved supplying bioactive metabolites from the fermentation product
Indirect action involved reprogramming the gut microbiota composition
The Firmicutes/Bacteroidetes ratio was normalized by FWB treatment
Key SCFA-producing genera including Alistipes_A and Duncaniella were enriched following FWB intervention
Results
FWB treatment enriched key SCFA-producing gut microbial genera, specifically Alistipes_A and Duncaniella, in constipated mice.
Gut microbiota composition was analyzed as part of the mechanistic evaluation
Alistipes_A and Duncaniella were specifically identified as enriched SCFA-producing genera
The Firmicutes/Bacteroidetes ratio was normalized, indicating broad microbiota rebalancing
Microbiota reprogramming was identified as an indirect mechanism by which FWB exerted its effects
What This Means
This research suggests that two industrial waste streams from wheat processing — wheat bran and wheat starch process water — can be transformed into a health-promoting ingredient by fermenting them with a beneficial bacterial strain called Lactobacillus paracasei EG9. The resulting product, called FWB, was enriched with short-chain fatty acids and other bioactive compounds during fermentation. When given to mice that had been made constipated using a drug called loperamide, FWB helped relieve constipation, but interestingly, the relationship between dose and benefit was not straightforward — there was an optimal dose that worked best rather than a simple 'more is better' pattern.
At the best dose, FWB sped up digestive movement through the gut, reduced inflammation throughout the body, and helped repair the lining of the colon. The researchers identified two ways FWB achieves these effects: first, by directly delivering beneficial metabolites produced during fermentation, and second, by reshaping the community of bacteria living in the gut. Specifically, FWB restored a healthier balance between two major bacterial groups (Firmicutes and Bacteroidetes) and increased the abundance of bacteria known to produce short-chain fatty acids, including Alistipes_A and Duncaniella.
This research suggests that fermenting wheat industry by-products could be a sustainable way to create functional food ingredients that support gut health. Rather than discarding these nutrient-rich waste materials, they could potentially be repurposed into dietary products designed to help people experiencing constipation, while also contributing to more environmentally responsible food manufacturing.
Cai J, Wang J, Li H, Liao A, Hou Y, Huang J, et al.. (2026). Study on the preparation of postbiotic elements by fermentation of wheat by-products and their role in improving constipation.. Food & function. https://doi.org/10.1039/d5fo04139b