Modulative effect of Physalis alkekengi on both gut bacterial and fungal micro-ecosystem

Gut microbiome is an intricate micro-ecosystem mediating the human health and drug efficacy. Physalis alkekengi (PAL) is an edible and time-honored traditional Chinese medicine. Several pharmacological effects of PAL have been verified and gut bacteria are implied in its therapeutic actions. However, the detailed modulation of PAL on gut bacterial species and on gut fungi remains largely unknown. We, therefore, designed a preliminary experiment in normal mice to reveal the modulation effect of PAL on both gut bacteria and fungi, and explore the interaction between them.

Herein, the aqueous extract of PAL was orally administrated to normal C57BL/6 mice for four weeks. The full-length 16S rRNA and ITS1/2 gene sequencing were explored to detect the taxa of gut bacteria and gut fungi after PAL treatment, respectively.

Oral administration of PAL notably enriched anti-inflammatory bacterial species such as Duncaniella spp. and Kineothrix alysoides, whereas decreased pro-inflammatory species such as Mucispirillum schaedleri. Simultaneously, PAL increased the abundance of gut fungi Aspergillus ochraceus, Cladosporium sp. and Alternaria sp., and decreased Penicillium janthinellum. Correlation network analysis identified two co-existing microbial groups (groups 1 and 2) that were negatively associated with each other. The group 1 comprised PAL-enriched bacteria and fungi, while group 2 was mainly normal chow-enriched bacteria and fungi. In group 1, Antrodia monomitica, Aspergillus clavatus, Mortierella kuhlmanii and Sarcinomyces sp. MA 4787 were positively correlated with Bifidobacterium globosum, Romboutsia ilealis and so on. In group 2, Chaetomium subspirilliferum, Septoria orchidearum and Cephaliophora tropica were positively related to Lactobacillus spp.

Altogether, this preliminary study first demonstrated the modulation effect of PAL on both gut bacteria and gut fungi, which may shed light on the elucidation of PAL's pharmacological mechanism.