Bacterial contribution to oral disease has been studied in young children, but there is a lack of data addressing the developmental perspective in edentulous infants. Our primary objectives were to use pyrosequencing to phylogenetically characterize the salivary bacterial microbiome of edentulous infants and to make comparisons against their mothers. Saliva samples were collected from 5 edentulous infants (mean age = 4.6±1.2 mo old) and their mothers or primary care givers (mean age = 30.8±9.5 y old). Salivary DNA was extracted, used to generate DNA amplicons of the V4–V6 hypervariable region of the bacterial 16S rDNA gene, and subjected to 454-pyrosequencing. On average, over 80,000 sequences per sample were generated. High bacterial diversity was noted in the saliva of adults [1012 operational taxonomical units (OTU) at 3% divergence] and infants (578 OTU at 3% divergence). Firmicutes, Proteobacteria, Actinobacteria, and Fusobacteria were predominant bacterial phyla present in all samples. A total of 397 bacterial genera were present in our dataset. Of the 28 genera different (P<0.05) between infants and adults, 27 had a greater prevalence in adults. The exception was Streptococcus, which was the predominant genera in infant saliva (62.2% in infants vs. 20.4% in adults; P<0.05). Veillonella, Neisseria, Rothia, Haemophilus, Gemella, Granulicatella, Leptotrichia, and Fusobacterium were also predominant genera in infant samples, while Haemophilus, Neisseria, Veillonella, Fusobacterium, Oribacterium, Rothia, Treponema, and Actinomyces were predominant in adults. Our data demonstrate that although the adult saliva bacterial microbiome had a greater OTU count than infants, a rich bacterial community exists in the infant oral cavity prior to tooth eruption. Streptococcus, Veillonella, and Neisseria are the predominant bacterial genera present in infants. Further research is required to characterize the development of oral microbiota early in life and identify environmental factors that impact colonization and oral and gastrointestinal disease risk.

Fructans markedly shifted gut microbiota and improved intestinal physiology in obese mice, but the mechanisms by which they affect gut integrity and inflammation in the obese are still unknown.

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Obesity is associated with compromised intestinal barrier function and shifts in microbiota that may contribute to inflammation. Previous research suggests benefits of supplemental fiber, but the impacts of fermentable vs. non‐fermentable fibers are not well understood.OBJECTIVETo determine the impact of cellulose vs. fructan (short‐chain fructooligosaccharides [scFOS] or inulin) supplementation on fecal microbiota and gut physiology in obese mice.METHODS18‐wk old C57BL/6J mice (n=6/group) were fed high‐fat diets (45% kcal fat) containing 5% cellulose, 10% cellulose, 10% scFOS or 10% inulin for 4‐wk. Cecum and distal colon were collected to assess barrier function, histomorphology and gene expression. Fecal DNA was extracted, followed by 16S rRNA amplicon Illumina MiSeq sequencing and analysis with QIIME 1.8.0.RESULTSBoth fructans increased (p<0.05) intestinal transmural resistance and crypt depth but reduced (p<0.05) mRNA abundance of ZO‐1 and occludin. Principal coordinates analysis (PCoA) of weighted and unweighted UniFrac distances of fecal microbiota revealed a sharp separation (p<0.05) between fructan and cellulose groups. Alpha diversity measures revealed lower (p<0.05) species richness with fructan supplementation. Fructans reduced (p<0.05) the relative abundance of Firmicutes and increased (p<0.05) Actinobacteria and Verrucomicrobia (Akkermansia).CONCLUSIONFructan supplementation may modulate gut microbiota and physiological responses via multiple mechanisms.

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