Salivary microbiota characterization of Yerba Mate consumers in Uruguay

Introduction: Yerba Mate (YM) is a green-colored infusion, derived from the Ilex paraguariensis plant, very popular and commonly consumed in Latin American countries (southern Brazil, Argentina, Paraguay, and Uruguay), rapidly gaining penetration in global markets, It’s a beverage rich in polyphenols, alkaloids, and saponins, making its impact on the oral microbiome particularly interesting. Objectives: This study aimed to characterize the composition of salivary microbiota in Uruguayan YM consumers and non-consumers, exploring potential implications for oral health. Materials and methods: Salivary samples were collected from 24 YM consumers and 28 non-consumers in Uruguay (n = 52). Participants were dentistry students, aged 18 to 35, with no reported pathologies and who had no oral conditions after visual inspection. 16S rRNA gene metabarcoding Illumina sequencing was employed to analyze their microbial composition. Bioinformatic analysis was conducted to identify and compare microbial taxa between the two groups. Relevant demographic and dietary data were also collected and analyzed. Results: The salivary microbiome of YM consumers is not completely different from non-consumers, however, several particular characteristics were found in each group. Both YM consumers and non-consumers exhibited a high relative abundance of Streptococcus species, with Streptococcus oralis being more abundant in a subset of non-consumers suggesting that YM may help maintain a balanced oral microbiota. Although no significant differences were observed in the Shannon diversity index, YM consumers might have a more diverse microbiome than non-consumers (YM consumers showed significantly higher species richness (Chao1 index), a greater number of amplicon sequence variants (ASVs), and broader microbial diversity, as confirmed by multivariate analyses). While the presence of Prevotella spp. in YM consumers aligns with previous research on polyphenol-rich beverages, its role in oral health warrants further investigation. Conclusions: This study highlights the influence of YM consumption on salivary microbiota composition and diversity. YM consumption was associated with increased microbial diversity and species richness, which may contribute to oral microbiome resilience and health. These findings underscore the impact of dietary habits on oral microbial communities and their potential implications for oral health management and disease prevention.