Structural Modulation of Gut Bacterial and Fungal Community of C57BL/6 Mice by <i>Pseudobulbus Cremastrae Seu Pleionesaqueous</i> Extract

<sec><title>Backgrounds</title> <italic>Pseudobulbus Cremastrae Seu Pleiones</italic> (PC), a traditional Chinese medicine (TCM) is used to treat various cancersin the modern pharmacological research. However, the potential mechanisms remain uncertain. The gut microbiome is involved in the pharmacological activities of many TCMs. Contemporary investigations into the interactions between gut microbiota and medicine have predominantly fixated on gut bacteria and routinely disregarded gut fungi. Present study firstly investigated the effects of PC on both gut bacteria and fungi and their interactions to explore its pharmacological mechanism. </sec><sec><title>Methods</title> Eighteen normal C57BL/6 mice were divided into PC and negative control groups, and orally administered an aqueous PC extract (1 g raw herb/kg) or an equivalent volume of distilled water, respectively. Fecal samples were gathered after four weeks and then under-went sequencing of the full-length 16S rRNA and ITS1/2 genes. Cecal samples were additionally obtained for determination of short-chain fatty acid levels. </sec><sec><title>Results</title> PC augmented the population of SCFA-producing bacteria like <italic>Duncaniellamuris</italic>, <italic>Duncanielladubosii, Kineothrix alysoides</italic> and <italic>Faecalimonas umbilicata</italic>, with a concomitant rise in cecal acetate and propionate amounts. In addition, PC significantly increased some potential beneficial fungi, such as <italic>Cladosporium sp</italic>., <italic>Psathyrella candolleana</italic>, <italic>Nigrospora sphaerica</italic>, and decreased some common fungi, like <italic>Aspergillus spp</italic>., <italic>Penicillium spp</italic>., <italic>Cosmospora viridescens</italic>. The interaction network demonstrated a complex relationship between gut bacteria and fungi after PC treatment. </sec><sec><title>Conclusion</title> These results suggest close links between an enriched abundance of SCFA-producing bacteria, gut fungi alterations, and anti-cancer effect of PC, highlighting the importance of gut fungi in mediating the in vivo effects of drugs. </sec>