Alleviation of dental caries by use of isolated potential probiotic and its characterization

Streptococcus mutans plays a major role in biofilm formation and pathogenic bacterial adhesion. Here we investigated the abilities of our isolates from diverse conventional sources to characterize the beneficial bacteria for inhibition of S. mutans. Enterobacter cloacae PS-74, a beneficial bacteria isolated from yoghurt, is gram negative, rod shaped, and resistant to acid, bile salt, and amylase. PS-74 cell-free supernatants (CFS) demonstrated highest zone of inhibition of 29 ± 1.7 mm. Further, the minimum inhibitory concentration (MIC) value of CFS PS-74 was recorded to be 10 μL and its minimum bactericidal concentration (MBC) value was found to be 15μL which led to 99.9% log reduction of S. mutans. Moreover, the biofilm formation was reduced by 84.91% at MIC15 of CFS PS-74 which alleviate the dental caries formation by S. mutans. This is the first report on E. cloacae PS-74, which was studied for its probiotic properties to inhibit S. mutans MTCC-890 due to the production of organic acids and employed in oral treatment.

Anticariogenic Activity of Black Tea: An In Vivo Study

BACKGROUND

The prevention of dental caries has always remained a challenge. Caries prevention through dietary intervention holds promise. Studies have revealed that several constituents present in tea have anticariogenic properties. Tea is a widely consumed beverage and hence could be utilized as a suitable caries preventive agent. The purpose of this study was to determine the effect of black tea on caries progression in experimental animals.

MATERIALS AND METHODS

This study was carried out in 17-day-old albino rat pups. The animals were divided into three groups, with eight animals in each group. They were fed on a cariogenic diet (MIT 200) and inoculated with Streptococcus mutans. Group I was given MIT 200 with water, Group II was placed on MIT 200 with black tea, and Group III was placed on MIT 200 with fluoridated water for a period of 45 days. After 45 days, the animals were killed under ether anesthesia, and their teeth were examined for caries.

RESULTS

The carious lesions were scored for the first two molars in each quadrant. In each group, a total of 64 teeth were examined. The caries score between the upper and lower jaws was compared using ANOVA.

CONCLUSION

From this study, it may be inferred that drinking black tea reduced the development of dental caries in young rats fed on a cariogenic diet. The tea used for this study was prepared using fluoride-free water, so we can assume that besides fluoride, certain components are present in tea leaves that possess anticariogenic properties.

Antibiofilm Efficacies of Flavonoid-Rich Sweet Orange Waste Extract against Dual-Species Biofilms

The current study evaluated the antibacterial properties of industrial sweet orange waste extracts (ISOWEs), which are a rich source of flavonoids. The ISOWEs exhibited antibacterial activity towards the dental cariogenic pathogens Streptococcus mutans and Lactobacillus casei with 13.0 ± 2.0 and 20.0 ± 2.0 mg/mL for MIC (minimum inhibitory concentration) and 37.7 ± 1.5 and 43.3 ± 2.1 mg/mL for MBC (minimum bactericidal concentration), respectively. When evaluated in a 7-day dual-species oral biofilm model, ISOWEs dose-dependently reduced the viable bacteria count, and demonstrated strong synergistic effects when combined with the anti-septic chlorhexidine (at 0.1 and 0.2%). Similarly, confocal microscopy confirmed the anti-cariogenic properties of ISOWEs, alone and in combination with chlorhexidine. The citrus flavonoids contributed differently to these effects, with the flavones (nobiletin, tangeretin and sinensetin) demonstrating significantly lower MICs and MBCs compared to the flavanones hesperidin and narirutin. In conclusion, our study demonstrated the potential of citrus waste as a currently underutilised source of flavonoids for antimicrobial applications, such as in dental health.

Anticariogenic Activity of Agarobiose and Agarooligosaccharides Derived from Red Macroalgae

3,6-Anhydro-l-galactose (AHG) produced from agarose in red macroalgae was recently suggested as an anticariogenic sugar to replace widely used xylitol. However, the multi-step process for obtaining monomeric sugar AHG from agarose may be expensive. Generally, it is easier to obtain oligosaccharides than monosaccharides from polysaccharides. Therefore, a one-step process to obtain agarobiose (AB) from agarose was recently developed, and here, we suggest AB as a new anticariogenic agent, owing to its anticariogenic activity against Streptococcus mutans. Among AHG-containing oligosaccharides, AB, neoagarobiose (NAB), agarooligosaccharides (AOSs), and neoagarooligosaccharides (NAOSs), AB showed higher inhibitory activity than AOSs against the growth and lactic acid production of S. mutans; no such inhibitory activity was observed for NAB and NAOSs. This inhibitory effect of AB was comparable to the previously reported inhibitory activity of AHG against S. mutans. These results suggest that AB, which can be more economically and simply produced than AHG, may serve as an anticariogenic sugar.

Determination of antibacterial activity and metabolite profile of Ruta graveolens against Streptococcus mutans and Streptococcus sobrinus

BACKGROUND

Ruta graveolens is one of the most used phytomedicines. To date, there is no report of determining the bioactivity of R. graveolens against cariogenic causing bacteria (Streptococcus mutans and Streptococcus sobrinus).

OBJECTIVE

The objective of the present study was to determine the antibacterial activity and metabolite profile of R. graveolens against S. mutans and S. sobrinus.

MATERIALS AND METHODS

R. graveolens plant material was collected and processed in the month of February. The plant material was extracted by Soxhlet apparatus using methanol solvent. Two strains of S. mutans and two strains of S. sobrinus were isolated from dental caries-active participants and cultured on mitis salivarius-bacitracin agar. The antibacterial susceptibility testing of methanolic extract of R. graveolens was performed by disc diffusion method. The metabolite profile of the plant extract was determined using electrospray ionization-tandem mass spectrometry.

RESULTS

The methanolic extract of R. graveolens showed a promising antibacterial activity against S. mutans and S. sobrinus. Two compounds named γ-fagarine and kokusaginine were identified from the methanolic extract of R. graveolens.

CONCLUSION

The study concluded that R. graveolens contains significant antibacterial activity. However, further investigations are suggested to understand the anticaries properties of these pure compounds.

through ¹H-NMR-Based Metabolomics Approach

The aim of this study was to determine the effects of different solvents for extraction, liquid⁻liquid partition, and concentrations of extracts and fractions of Piper cubeba L. on anticariogenic; antibacterial and anti-inflammatory activity against oral bacteria. Furthermore, ¹H-Nuclear Magnetic Resonance (NMR) coupled with multivariate data analysis (MVDA) was applied to discriminate between the extracts and fractions and examine the metabolites that correlate to the bioactivities. All tested bacteria were susceptible to Piper cubeba L. extracts and fractions. Different solvents extraction, liquid⁻liquid partition and concentrations of extracts and fractions have partially influenced the antibacterial activity. MTT assay showed that P. cubeba L. extracts and fractions were not toxic to RAW 264.7 cells at selected concentrations. Anti-inflammatory activity evaluated by nitric oxide (NO) production in lipopolysaccharide (LPS) stimulated cells showed a reduction in NO production in cells treated with P. cubeba L. extracts and fractions, compared to those without treatment. Twelve putative metabolites have been identified, which are (1) cubebin, (2) yatein, (3) hinokinin, (4) dihydrocubebin, (5) dihydroclusin, (6) cubebinin, (7) magnosalin, (8) p-cymene, (9) piperidine, (10) cubebol, (11) d-germacrene and (12) ledol. Different extraction and liquid⁻liquid partition solvents caused separation in principal component analysis (PCA) models. The partial least squares (PLS) models showed that higher anticariogenic activity was related more to the polar solvents, despite some of the active metabolites also present in the non-polar solvents. Hence, P. cubeba L. extracts and fractions exhibited antibacterial and anti-inflammatory activity and have potential to be developed as the anticariogenic agent.