Pu’er Tea Isolated Paenibacillus yunnanensis and Bacillus camelliae Affect the Development of Streptococcus Mutans Biofilm Through the Co-aggregation

As a predominant etiological agent of dental caries, Streptococcus mutans plays a pivotal role in the development of dental plaque. Given that the fermentative bacteria from Pu’er tea exert inhibitory effects on Streptococcus mutans, in this study, we examined the co-aggregation interactions between nine strains of Pu’er tea fermentative bacteria and three strains of Streptococcus mutans. Notably, Bacillus camelliae 7578-1 ^T and Paenibacillus yunnanensis YN2^T demonstrated robust co-aggregation capabilities. Treatments with sugars, heat, proteases, and amino acids, revealed that protein and saccharide molecules on bacterial surfaces significantly contribute to intergeneric co-aggregation. Importantly, strains 7578-1 ^T and YN2^T reduced the biofilm biomass and culturable cell counts of Streptococcus mutans, indicating their potential for maintaining oral health. Furthermore, hydrophobic interactions, disulfide bonding, and hydrogen bonding were observed in dual-species biofilms. This research elucidates the functional significance of Pu’er tea fermentative bacteria in regulating oral microbial communities and lays a groundwork for further investigation into their potential utility in the prevention of dental caries.