Effect of Italian "Grana Padano" Cheese on the Oral Microbiota Composition: A 16S rRNA Metabarcoding Approach

Milk and Cheese are considered functional foods and have a role on oral health. There are several mechanisms by which cheese exerts its beneficial effects on teeth (Ingered et al. 2002)). The aim of the present study was to examine whether short-term consumption of hard cheese would affect the oral cariogenic microbial flora of healthy adults. Next Generation Sequencing approach was applied to study the effect of Italian "Grana Padano" (GP), as a prototype of typical hard cheese, on oral microbiota composition. Twenty oral healthy adults were instructed to eat 25gr of GP cheese for 5 consecutive days and supra-gingival oral samples were collected at three time points. Metabarcoded 16S rRNA sequences were obtained both from oral samples and GP cheese using MySeq platform and analyzed against Human Oral Microbiome database. Taxonomic analyses revealed that Firmicutes was the most abundant phylum, followed by Proteobacteria and Actinobacteria. Principal component analyses revealed that eating Italian "GP" cheese for 5 days decreased the amount of several species such as Lactobacillus crispatus, Lactobacillus sp, Lactobacillus acidophylus and Lachnoanaerobaculum saburreum known to have a effect on developing caries. Our results revealed that a portion of GP cheese eaten after dinner provides important micronutrients and improves the oral health reducing the amount of several bacteria associated to dental caries.