Objective:

2

To investigate the regulatory effects of two traditional mineral medicines (TMMs)

Gypsum Fibrosum

(Shigao

GF) and

Terra Flava Usta

(Zaoxintu

TFU)

on gut-beneficial bacteria in mice

and preliminarily explore their mechanisms of action.

Methods:

2

Mice were randomly divided into 3 groups (

n

=10 per group): the control group (standard diet)

the GF group (diet supplemented with 2% GF)

and the TFU group (diet supplemented with 2% TFU). After 4-week intervention

16S rRNA gene sequencing was used to analyze the changes in the gut microbiota (GM). Scanning electron microscopy

in combination with coumarin A tetramethyl rhodamine conjugate and Hoechst stainings

was used to observe the bacteria and biofilm formation.

Results:

2

Principal coordinate analysis revealed that GF and TFU significantly altered the GM composition in mice. Further analysis revealed that GF and TFU affected different types of gut bacteria

suggesting that different TMMs may selectively modulate specific bacterial populations. For certain bacteria

such as

Faecalibaculum

and

Ileibacterium

both GF and TFU exhibited growth-promoting effects

implying that they may be sensitive to TMMs and that different TMMs can increase their abundance through their respective mechanisms. Notably

Lactobacillus reuteri

a widely recognized and used probiotic

was significantly enriched in the GF group. Random forest analysis identified

Ileibacterium valens

as a potential indicator bacterium for TMMs' impact on GM. Further mechanistic studies showed that gut bacteria formed biofilm structures on the TFU surface.

Conclusions:

2

This study provides new insights into the interaction between TMMs and GM. As safe and effective natural clays

GF and TFU hold promise as potential candidates for prebiotic development.