# Dietary Administration of a Soybean Fermented Preparation Reshapes Gut Microbial Community Structure and Colonic Mucosal Features in BALB/c Mice

## TL;DR

A soybean fermented product changed gut microbes and increased goblet cells in mice over time, suggesting potential effects on gut health.

## Contribution

This study reveals long-term effects of a soybean fermented preparation on gut microbial structure and colonic mucosal features in mice.

## Key findings

- SFP supplementation caused significant β-diversity separation in gut microbes at 30 and 60 days.
- SFP increased goblet cell density in the colon of treated mice.
- SFP reduced microbial diversity evenness and increased specific taxa like Akkermansia and Lactobacillus.

## Abstract

Background/Aim: Fermented soybean-based products are known to influence gut microbial composition; however, the long-term effects of multicomponent soybean fermented preparations on gut microbiota and colonic mucosal features remain insufficiently characterized. This study examined the effects of a commercially available soybean fermented preparation (SFP), containing additional fermented plant and marine derived components, on gut microbial community structure and colonic histological features in BALB/c mice. Methods: BALB/c mice received oral SFP (1000 mg/kg) for 30 and 60 days. Gut microbial communities were analyzed using full-length rRNA operon sequencing. Colonic mucosal architecture and goblet cell density were evaluated via histological analysis (H&E). Results: SFP supplementation induced significant β-diversity separation at both 30 and 60 days (p < 0.05), indicating consistent restructuring of the gut microbial community. While alpha diversity (Observed OTUs) remained stable at 30 days, Shannon and Simpson indices were significantly reduced at 60 days (p = 0.001), indicating reduced community evenness driven by increased dominance of specific taxa, including Duncaniella. At the genus level, SFP administration was associated with increased relative abundances of Akkermansia, Lactobacillus, and Duncaniella, accompanied by reductions in several genera previously linked to dysbiosis. Histological analysis demonstrated a significant increase in goblet cell density (p < 0.01) in SFP-treated mice. Conclusions: Long-term SFP supplementation was associated with sustained alterations in gut microbial composition and measurable histological changes in the colonic mucosa. While these findings indicate that SFP intake influences microbial structure and goblet cell abundance, further studies are required to determine the functional and physiological implications of these changes, particularly in relation to epithelial barrier function and host health.