Two strains of previously unknown Gram-negative cocci, T1-7^T and S6-16, were isolated from the oral cavity of healthy Japanese children. The two strains showed atypical phenotypic characteristics of members of the genus Veillonella , including catalase production. Sequencing of their 16S rRNA genes confirmed that they belong to genus Veillonella . Under anaerobic conditions, the two strains produced acetic acid and propionic acid as metabolic end-products in a trypticase–yeast extract–haemin medium containing 1 % (w/v) glucose, 1 % (w/v) fructose and 1 % (v/v) sodium lactate. Comparative analysis of the 16S rRNA, dnaK, rpoB and gltA gene sequences revealed that the two strains are phylogenetically homogeneous and comprise a distinct, novel lineage within the genus Veillonella . The sequences from the two strains shared the highest similarity, at 99.9, 95.8, 96.9 and 96.7 %, using the partial 16S rRNA, dnaK, rpoB and gltA gene sequences, respectively, with the type strains of the two most closely related species, Veillonella dispar ATCC 17748^T and Veillonella infantium JCM 31738^T. Furthermore, strain T1-7^T shared the highest average nucleotide identity (ANI) value (94.06 %) with type strain of the most closely related species, V. infantium . At the same time, strain T1-7^T showed the highest digital DNA–DNA hybridization (dDDH) value (55.5 %) with the type strain of V. infantium . The two strains reported in this study were distinguished from the previously reported species from the genus Veillonella based on catalase production, partial dnaK, rpoB and gltA sequences, average ANI and dDDH values. Based on these observations, the two strains represent a novel species, for which the name Veillonella nakazawae sp. nov. is proposed. The type strain is T1-7^T (JCM 33966^T=CCUG 74597^T).

Impaired development that causes stunting is one of the most common health problems in Indonesia. In particular, the highest number of cases of stunting in Indonesia was reported in the East Nusa Tenggara (NTT) province. Previous studies have shown a tendency for deteriorating oral hygiene in children with a poor nutritional status. In addition, a higher proportion of oral Veillonella has been reported in children with poor oral hygiene. However, the relationship between populations of oral Veillonella and stunting has not been studied before. Therefore, this study aimed to analyze the oral Veillonella profile in the dental biofilms of healthy and stunted children aged 6–7 years. The participants were 60 elementary school students in the Nangapanda District, Ende, NTT, Indonesia. In this study, real-time polymerase chain reaction was used to examine dental biofilm samples from the healthy (n = 31) and stunted (n = 29) groups. The results revealed that seven oral Veillonella species were found in all groups. However, the number of four oral Veillonella species significantly differed between the healthy and stunted groups: V. denticariosi, V. infantium, V. rogosae, and V. tobetsuensis. This is the first study to demonstrate a potential association between oral Veillonella species and stunting in children.

Objective The aim of this study was to evaluate the effect of reuterin produced by a novel probiotic strain of Lactobacillus reuteri against periodontal biofilms. Materials and Methods L. reuteri LC382415 (an indigenous Indonesian strain) was cultured in Man, Rogosa, and Sharpe (MRS) agar in anaerobic conditions for 24 hours. To isolate reuterin, L. reuteri was suspended in 300-mM glycerol in MRS broth and incubated under anaerobic conditions for 3 hours, and the supernatant fraction was filtered. The presence of reuterin was confirmed by sodium dodecyl sulfate–polyacrylamide gel electrophoresis (SDS-PAGE), and its concentration was determined. The effect of reuterin on Porphyromonas gingivalis ATCC 33277 and T. denticola ATCC 35405 biofilms was evaluated using biofilm assays. Biofilms were formed by incubating bacteria in 96-well microplates for 48 hours. A dose-dependent experiment was performed with reuterin concentrations of 12.5, 25, 50, and 100 μg/mL on biofilms. The inhibitory effect was measured at 1, 3, 6, and 24 hours. The biofilm masses were measured at 490 nm. Statistical analysis was using one-way ANOVA. Results The SDS-PAGE assay confirmed the presence of reuterin (52 kDa) in the culture supernatant of the L. reuteri strain. Reuterin in a concentration as low as 12.5 μg/mL significantly inhibited single- and mixed-species biofilms (p < 0.05). Conclusions This is the first study to demonstrate the promising effect of reuterin isolated from L. reuteri LC382415 against periodontal bacteria. Further studies are warranted to explore the mechanism of this active component.

Objective:The studies on the influence of geographical and socio-economic factors on the oral microbiome remain underrepresented. The Indonesia basic health research (RISKESDAS) 2018, showed an increasing trend in non-communicable diseases compared with the previous report in 2013. The prevalence of diabetes, heart disease, hypertension, and obesity are reported to be higher in urban areas than in rural areas. Interestingly, non-communicable diseases were found to be more prevalent in women than men. This pilot study aimed to examine the oral health and oral microbiome derived from tongue samples of healthy Indonesian women from urban and rural areas.Methods:Twenty women aged 21–47 years old from West Jakarta, residents of DKI Jakarta (n= 10) as representative of the urban area, and residents of Ende, Nangapanda, East Nusa Tenggara (n= 10) as representative of the rural area were recruited for this pilot study. The participants were evaluated by the Simplified Oral Hygiene Index (OHI-S) according to the criteria of Greene and Vermillion and divided into three groups. High-throughput DNA sequencing was performed on an Illumina iSeq 100 platform.Results:The principal component analysis displayed a marked difference in the bacterial community profiles between the urban and rural localities. The presence of manifest was associated with increased diversity and an altered oral bacterial community profile in the urban women. Two bacterial taxa were present at significantly higher levels (adjustedp< 0.01) in the urban oral microflora (GenusPrevotellaandLeptotricia) could account for this difference irrespective of the individual oral hygiene status. The linear discriminant analysis effect size (LEfSe) analysis revealed several distinct urban biomarkers. At the species level,Leptotrichia wadei, Prevotella melaninogenica, Prevotella jejuni, andP. histicola, show an excellent discriminatory potential for distinguishing the oral microflora in women between urban and rural areas. Further, using SparCC co-occurrence network analysis, the co-occurrence pattern in the dominant core oral microbiome assembly was observed to be specific to its ecological niche between two populations.Conclusions:This is the first pilot study demonstrating the characterization of the oral microbiome in Indonesian women in urban and rural areas. We found that the oral microbiome in women displays distinct patterns consistent with geographic locality. The specific characterization of the microbiota of Indonesian women is likely linked to geographical specific dietary habits, cultural habits, and socio-economic status or the population studied.

Background: The benefits of probiotics for human health have long been proven. Probiotic Lactobacillus reuteri, can produce a beneficial broad-spectrum antibacterial compound called reuterin by metabolizing glycerol. Objective: The aim of the study was to investigate the effect of the Indonesian strain of L. reuteri LC382415 on mono- and dual-species Streptococcus mutans and Streptococcus sanguinis biofilms in vitro. Methods: Streptococcus mutans and S. sanguinis were cultured in BHI broth. Lactobacillus reuteri LC382415 was inoculated on MRS agar. The different concentrations effect of L. reuteri (1×10⁴, 1×10⁶, and 1×10⁸ CFU/mL) with and without glycerol supplementation on microbial biofilms were examined using a biofilm assay after incubation for 1,3,6, and 24-h. The biofilm mass optical density was measured with a microplate spectrophotometer at 490 nm. Chlorhexidine gluconate (0.2%) was used as a positive control, and wells without treatment were used as negative controls. Results: A significant reduction in mono- and dual-species S. mutans and S. sanguinis biofilm formation was observed after treatment with all concentrations of L.reuteri and after all incubation periods (p<0.05) with or without glycerol supplementation. The concentration of 1×10⁴ CFU/mL after 3-h incubation was the most effective in inhibiting biofilm formation, with 87.8% S. mutans, 95.9% S. sanguinis, and 80.4% dual-species biofilm reduction compared to the negative control (p<0.05). Conclusion: The Indonesian strain of L. reuteri effectively reduces mono- and dual-species S.mutans and S. sanguinis biofilms. This suggests that it may be useful in preventing biofilm formation in oral cavities. Future studies on the mechanism of action of this active component are warranted.