Impact of environmental pH on the structure and diversity of oral microbiota: an in vitro study

The oral microbiome significantly impacts both oral and systemic health. Although in vivo studies have explored the relationship between the oral environment and microbial communities, precise analysis of environmental pH effects on the oral microbiota remains challenging due to their complexity and external influences. This study aimed to investigate how environmental pH affects the structure and diversity of the oral microbiota in vitro. Tongue coating samples from 10 participants were cultured anaerobically in media adjusted to six pH levels. After DNA extraction, high-throughput sequencing of the V3-V4 region of the 16S rRNA gene was performed. Microbial diversity was analyzed using alpha and beta diversity indices, and differential taxa were identified using LEfSe.