Effects of Lactobacillus casei Shirota intake on caries risk in children

Advances in characterization of probiotics and challenges in industrial application

An unbalanced diet and poor lifestyle are common reasons for numerous health complications in humans. Probiotics are known to provide substantial benefits to human health by producing several bioactive compounds, vitamins, short-chain fatty acids and short peptides. Diets that contain probiotics are limited to curd, yoghurt, kefir, kimchi, etc. However, exploring the identification of more potential probiotics and enhancing their commercial application to improve the nutritional quality would be a significant step to utilizing the maximum benefits. The complex evolution patterns among the probiotics are the hurdles in their characterization and adequate application in the industries and dairy products. This article has mainly discussed the molecular methods of characterization that are based on the analysis of ribosomal RNA, whole genome, and protein markers and profiles. It also has critically emphasized the emerging challenges in industrial applications of probiotics.

The strategic role of biotics in dental caries prevention: A scoping review

Dental caries is a global oral health issue that is prevalent and preventable. Biotics (probiotics, prebiotics, symbiotics, and postbiotics) are recommended as low-cost methods for preventing dental caries. This scoping review aimed to critically review the scientific evidence concerning the role of biotics in caries prevention and maintaining oral health benefits. A systematic search was conducted in several databases from 2012 onward, using specific keywords. The search resulted in 69 articles. While there is limited research on the mechanism of biotics in preventing caries, numerous studies have investigated the impacts of probiotics on decreasing caries risk factors. Probiotics can reduce cariogenic bacteria, reduce acidogenic bacteria, increase pH, and produce antimicrobial compounds. Probiotics can be used as a therapeutic approach to manage caries by restoring eubiosis at the host-microbial interface, which may not be accomplished with traditional therapies. Its positive effect on reducing dental caries is influenced by the choice of potent probiotic strains, appropriate dosage, treatment period, vehicle, and microbial interaction with the host. Specific oral bacteria have also been shown to utilize prebiotics such as urea and arginine, increasing pH levels. This highlights the potential of combining prebiotic and probiotic bacteria for caries prevention. In addition, this review is focused on bacterial-derived compounds, namely postbiotics, due to their valuable effects in preventing caries. Biotics have demonstrated potential in preventing dental caries and maintaining oral health. Further research is needed to optimize their use and explore the potential of postbiotics for caries prevention.

Knowledge and Attitude of Dental Practitioners about Probiotics in Alkharj, Kingdom of Saudi Arabia

Background

Probiotics are dietary supplements have found their usage mainly for gastrointestinal problems. Recently, oral health benefits of probiotics are investigated and their use for prevention of oral diseases such as dental caries, periodontal problem, and halitosis are established.

Aim

The aim of the study is to assess the knowledge and attitude about probiotics among private dental practitioners in Alkharj, Saudi Arabia.

Material and Methods

A cross-sectional study conducted on a total of 170 dentists practicing in alkharj. The subjects completed a questionnaire that consisted of information related to assess the awareness, knowledge, and attitude about probiotics. The collected data were expressed as number and percentages.

Results

96.47% of dentists were aware of the probiotics, while 82.3% of dentists think probiotics helps in improving health. 76.2% have used probiotics for some reason. 81.7% were of the intention to use probiotics for prevention of oral disease.

Conclusion

This study revealed good awareness of probiotics among dentists in Alkharj. Lack of adequate knowledge about use of probiotics for oral health needs to be addressed.

Inhibition of Streptococcus mutans Biofilm Formation by the Joint Action of Oxyresveratrol and Lactobacillus casei

Microbial dysbiosis in dental plaque contributes to the occurrence of dental caries, to which Streptococcus mutans is a major contributor. Lactobacillus casei can be used as probiotic therapy to treat caries by replacing S. mutans within the dental plaque. However, the effects of probiotic treatment are not always stable. Oxyresveratrol (ORV), a plant-derived polyphenol, displays opposite effects in that it inhibits cariogenic and promotes commensal bacteria. Thus, the objectives of this study are to investigate the effects of ORV on bacterial proportions in S. mutans-L. casei biofilm and to elucidate how ORV weakens the competitiveness of S. mutans. Quantitative real-time PCR confirms a decreased S. mutans-L. casei ratio in dual-species biofilm by action of ORV. The culture supernatant of L. casei after being incubated with ORV (ORVLC) is prepared to explore the joint action of ORV and L. casei. ORVLC displays the strongest anti-biofilm effect against S. mutans when compared with the effects of L. casei supernatant or ORV alone. As a result of this treatment, both exopolysaccharides and bacteria contents in the biofilm are greatly reduced. The biofilm is transformed from water-insoluble glucan-dominant to water-soluble glucan-dominant by ORVLC through the modulation of the glycometabolism-related genes of S. mutans. As for the interactions between ORV and L. casei, ORV promotes L. casei to produce acetic acid, which provides L. casei with a competitive advantage against S. mutans. Taken together, ORV may be very suitable as an adjuvant medicine for probiotic therapy in the control of dental caries. IMPORTANCE The homeostatic imbalance in dental plaque associated with a sharp increase in the number of cariogenic bacteria such as Streptococcus mutans is critical for the occurrence and development of caries. Probiotic therapy can restore ecological balance by replacing cariogenic pathogens with probiotics. The current study innovatively finds that oxyresveratrol, a natural polyphenol, can provide probiotic Lactobacillus casei with competitive dominance in its dual-species biofilm with S. mutans. The joint action of oxyresveratrol and L. casei strongly inhibits the biofilm formation of S. mutans. Additionally, oxyresveratrol promotes L. casei to produce acetic acid, which facilitates L. casei to compete with S. mutans. Through the effects of these two mechanisms, oxyresveratrol leads to a significantly decreased S. mutans-L. casei ratio in their dual-species biofilm. Thus, oxyresveratrol is speculated to be an ideal medicine for the prevention and treatment of caries by regulating oral flora balance.

The role of yogurt enriched with lactobacillus rhamnosus GG culture in dental caries prevention

Introduction/Objective. Contemporary tendencies suggest that probiotics can significantly reduce the prevalence of caries in children, so it can be considered that they have a positive effect on general and oral health. Lactobacillus rhamnosus GG (LGG) is a probiotic culture of particular importance in preventive dentistry. The aim was to assess the effects of consumption of probiotic strain Lactobacillus rhamnosus GG on the dental plaque accumulation in children with mixed dentition. Methods. Research included 90 children with mixed dentition (5-12 years old). First study group consumed 200 ml of Lactobacillus rhamnosus GG-enriched yogurt (B-Activ LGG, Dukat) daily for a period of 14 days, while the remaining 30 formed the second study group who consumed 200 ml of yogurt (Jogurt 1,5% milk fat, Imlek) with manually added powder from probiotic capsule (Wayaforte LGG capsule, Medis) daily for14 days. The control group consisted of 30 children who had regular diet during examination period. Silness-L?e plaque index and saliva pH (pH-Fix-0-14, Macherey-Nagel) were determined at baseline and also upon intervention completion. Results. An increase in pH values was observed in both study groups. In general sample, there is a significant decrease of mean plaque index values (p ? 0.001). Both study groups had significant decrease of mean plaque index values on the baseline and after 14 days consumption of yogurt. In the control group the number of subjects with decrease plaque index values did not correlate and no association was found. Conclusion. Consistent consumption of LGG culture-enriched yogurt inhibits dental film accumulation and promotes saliva pH increase in children with mixed dentition.

A Review of the Role of Probiotic Supplementation in Dental Caries

Dental diseases are among the common health issues experienced around the world. Dental caries is one of the most predominant oral diseases worldwide. Major factors associated with caries development include poor oral hygiene, the content of specific carbohydrates in the diet, dental biofilm formation, the cariogenic microbial load, reduction in salivary flow, insufficient fluoride exposure, gingival recession, genetic factors, and lack of personal attention to one's dental health. Several preventive measures have been implemented to reduce the risk of the development of caries. Probiotics are live microbes that when administered in suitable amounts confer health benefits on the host; they are recognized as potential adjunct therapeutic agents for several diseases. The present manuscript summarizes recent findings on the role of probiotics in dental caries prevention and the possible mechanisms of probiotic effects. Review of the literature indicates the regular consumption of probiotic products significantly reduced the risk of caries by inhibiting cariogenic bacteria and enriching commensal microbes in the oral cavity. Buffering the salivary pH, production of bacteriocin and enzymes (dextranase, mutanase, and urease), the capacity of competing for the adhesion and colonization on tooth surfaces are the possible mechanisms behind the beneficial effect of probiotics. Further studies are necessary to address the efficacy of long-term probiotic supplementation on the control of dental diseases and the influence of childhood probiotic supplementation on the risk of caries development.

Uncovering Prospective Role and Applications of Existing and New Nutraceuticals from Bacterial, Fungal, Algal and Cyanobacterial, and Plant Sources

Nutraceuticals are a category of products more often associated with food but having pharmaceuticals property and characteristics. However, there is still no internationally accepted concept of these food-pharmaceutical properties, and their interpretation can differ from country to country. Nutraceuticals are used as part of dietary supplements in most countries. They can be phytochemicals which are biologically active and have health benefits. These can be supplied as a supplement and/or as a functional food to the customer. For human health and longevity, these materials are likely to play a vital role. Consumption of these items is typical without a therapeutic prescription and/or supervision by the vast majority of the public. The development of nutraceuticals can be achieved through many bioresources and organisms. This review article will discuss the current research on nutraceuticals from different biological sources and their potential use as an agent for improving human health and well-being, as well as the gaps and future perspective of research related to nutraceutical development.

New Clinical Applications of Electrolyzed Water: A Review

As the situation of severe acute respiratory syndrome coronavirus type 2 (SARS-CoV-2) is still deteriorating, there has been a huge increase in the demand and use of disinfectants. Electrolyzed water (EW), as a novel broad-spectrum disinfectant and cleaner, has been widely used for several years. EW can be produced in an electrolysis chamber which contains dilute salt and tap water. It is an effective antimicrobial and antibiofilm agent, with several advantages such as on-the-spot, cheap, environmentally friendly and safe for human beings. Therefore, EW holds potential significance for high-risk settings in hospitals and other clinical facilities. EW can also be applied for wound healing, advanced tissue care, and dental clinics. The present review article highlights the latest developments and new perspectives of EW, especially in clinical fields. Furthermore, the main action modes of antibiofilm and antimicrobial will be summarized.

Effect of Lactobacillus brevis CD2 containing lozenges and plaque pH and cariogenic bacteria in diabetic children: a randomised clinical trial

Objective

The short-term effect (60 days) of Lactobacillus brevis CD2 lozenges vs placebo on variables related to caries and gingivitis in type 1 diabetic children was evaluated.

Material and methods

Eight diabetics (4–14 years old) were assigned to two groups (n = 34 subjects each), probiotic lozenges and placebo. Stimulated saliva for microbiological analysis and plaque pH were assessed at baseline (t₀), 30 days (t₁), 60 days (t₂) and in the follow-up period (90 days from baseline, t₃). Gingival status was assessed at t₀, t₂ and t₃. Two-way ANOVA assessed differences between groups.

Results

In the probiotic group, Streptococcus mutans bacterial density mean scores dropped from 3.11 ± 1.13 at baseline to 1.82 ± 0.72 (t₂) and to 2.06 ± 0.56 (t₃), while in the placebo group, the scores were 3.09 ± 0.8 (t₀), 2.82 ± 0.47 (t₂) and 3.11 ± 0.43 (t₃) (p < 0.01). Lowest and maximum pH fall increased in the probiotic group, from 5.37 ± 0.41 at baseline to 5.49 ± 0.24 at t₃ (p < 0.01) and from 1.20 ± 0.46 to 0.98 ± 0.29 (p = 0.02). Bleeding score decreased significantly in both groups, showing a statistically significant lower bleeding score at t₂ in the probiotic group (25.6%, 95% CI 21.5–32.7 vs 29.5%, 95% CI 25.2–34.9, p = 0.02).

Conclusions

Lactobacillus brevis CD2 has shown to improve caries-related risk factors and gingival health in diabetic children.

Clinical relevance

Lactobacillus brevis CD2 might contribute to improved oral health in type 1 diabetic children.

Electronic supplementary material

The online version of this article (10.1007/s00784-020-03342-0) contains supplementary material, which is available to authorized users.

The effect of commercial functional food with probiotics on microorganisms from early carious lesions

Caries rates in school-age children are still high enough to be the cause of serious concern for health systems in different countries. The biotechnology strategies studied to decrease these rates include the consumption of probiotics—available via a variety of functional foods obtainable on the market—that are able to inhibit bacteria associated with this disease. In this vein, the purpose of this study was to determine the effect of these foods on the growth of microorganisms in early carious lesions in children aged between 6 and 12. In the first phase, an agar well diffusion method was applied to selected foods, available in supermarkets, which contain probiotics that have already been shown to inhibit Streptococcusmutans (ATCC 25175), and to lower the pH in liquid culture media. In a second phase, these foods (n = 4) were examined in terms of their ability to inhibit the microorganisms in contact with early carious lesions in children and to reduce the pH of mixed cultures combined with the food. The results revealed that, of the foods tested, three inhibit the growth of microorganisms in carious lesions and, at the same time, lower the pH of the culture by more than 2.5 units. The food with the highest inhibitory capacity (14 mm, IQR 13–14) showed a similar effect among patients (P > 0.05), which together with the fact that its sugar concentration is less than 10%, makes it an ideal candidate for clinical study.

Effect of a novel synbiotic on Streptococcus mutans

We examined the effect of L-arginine - (i) on the growth of L. rhamnosus GG (LrG) and (ii) combined LrG synbiotic on the growth of cariogenic S. mutans. Viability of LrG was assessed using MTT/XTT assays, confocal imaging with ADS activity measurement. The effect of L-arginine (0.5%/1%/2%) (2×/24 h) with LrG on S. mutans was evaluated by measuring the colony forming units, biofilm biomass, real-time qPCR and confocal imaging. The pH of the spent media was measured immediately and 24 h post-treatment with assessment of lactic acid. The LrG viability was highest with 2% L-arginine (p < 0.001). Confocal imaging showed that 2% L-arginine increased biofilm thickness of LrG. The 2% L-arginine and LrG synbiotic significantly inhibited the growth of S. mutans (p < 0.001) reducing the viable counts (p = 0.002) and biofilm biomass (p < 0.001). The pH of spent media was the highest when treated with 2% L-arginine and LrG synbiotic (p < 0.001) with no difference between post-treatment and 24 h post-treatment (p > 0.05). Conversely, the 2% L-arginine and LrG synbiotic showed the lowest lactic acid production (p < 0.001). This study demonstrated that L-arginine enhanced the growth of LrG. The 2% L-arginine and LrG synbiotic synergistically inhibits the growth of S. mutans with significant potential to develop as an anti-caries regimen.

Inhibition of Streptococcus mutans by a commercial yogurt drink

Background/Purpose

Studies have been focused on using probiotics to prevent caries. The lactobacillus probiotic bacteria in Yakult^® (LcY) has been shown to inhibit the growth or biofilm formation of Streptococcus mutans. However, sucrose in Yakult^® raised concerns. The purpose of this study was to determine effects of Yakult^® on the growth and adhesion of S. mutans.

Materials and methods

S. mutans was grown in serial diluted Yakult^®, filtered Yakult^® or 20% heated Yakult^®. S. mutans was co-cultured with LcY in media with or without diluted filtered Yakult^®, or in LcY grown in media with or without sugars. Colony forming units and pH values of bacterial cultures were determined. SYTO 9-stained adhered bacteria were observed.

Results

Yakult^® inhibited the growth of S. mutans. Filtering or heating Yakult^® reduced its inhibitory ability against S. mutans. The inhibitory effect of LcY against S. mutans was enhanced when cultured in the presence of 20% filtered Yakult^®. LcY cultured in sucrose media for 24 h inhibited the growth of S. mutans, but this effect was less evident when LcY was grown for 48 h. LcY grown in glucose or lactose media similarly reduced S. mutans growth. Culturing S. mutans with LcY grown in sucrose or glucose media reduced bacterial adhesion. However, co-culturing S. mutans with LcY grown in the lactose media did not decrease bacterial adhesion.

Conclusion

Yakult^® and its probiotic content may inhibit S. mutans growth and the effect may be moderated by the type of sugar added for LcY cultivation.

Effects of a probiotic drink containing Lactobacillus casei strain Shirota on dental plaque microbiota

Objective

To investigate the effects of a probiotic drink containing Lactobacillus casei strain Shirota on dental plaque microbiota.

Methods

Caries-free young adults were administered a probiotic drink containing L. casei Shirota (Yakult) three times on day 1, then once daily for 28 days. Dental plaque samples were collected and analysed by 16S rRNA sequencing before (day 1), during (day 2), and one day following intervention (day 30).

Results

Out of samples from 10 included participants, 256 814 sequences passed through quality control, clustered into 170–234 different ‘species-level’ phylotypes. Actinobacteria, Bacteroidetes, Firmicutes, Fusobacteria and Proteobacteria were the most abundant phyla. Dental plaque microbiota composition significantly changed at different taxonomic levels following probiotic consumption. At genus level, the relative abundance of Veillonella and Kingella increased significantly following intervention, while that of Leptotrichia reduced significantly during intervention, but recovered to baseline level at day 30. Alpha diversity and overall structure of the dental plaque microbiota was not significantly impacted by the probiotic.

Conclusion

Yakult intake changed the abundance of some bacteria related to caries, suggesting that the change of composition may be beneficial to oral health, while the overall microbiota structure remained unaffected.

Probiotic Lactobacillus sp. inhibit growth, biofilm formation and gene expression of caries-inducing Streptococcus mutans

Streptococcus mutans contributes significantly to dental caries, which arises from homoeostasic imbalance between host and microbiota. We hypothesized that Lactobacillus sp. inhibits growth, biofilm formation and gene expression of Streptococcus mutans. Antibacterial (agar diffusion method) and antibiofilm (crystal violet assay) characteristics of probiotic Lactobacillus sp. against Streptococcus mutans (ATCC 25175) were evaluated. We investigated whether Lactobacillus casei (ATCC 393), Lactobacillus reuteri (ATCC 23272), Lactobacillus plantarum (ATCC 14917) or Lactobacillus salivarius (ATCC 11741) inhibit expression of Streptococcus mutans genes involved in biofilm formation, quorum sensing or stress survival using quantitative real-time polymerase chain reaction (qPCR). Growth changes (OD600) in the presence of pH-neutralized, catalase-treated or trypsin-treated Lactobacillus sp. supernatants were assessed to identify roles of organic acids, peroxides and bacteriocin. Susceptibility testing indicated antibacterial (pH-dependent) and antibiofilm activities of Lactobacillus sp. against Streptococcus mutans. Scanning electron microscopy revealed reduction in microcolony formation and exopolysaccharide structural changes. Of the oral normal flora, L. salivarius exhibited the highest antibiofilm and peroxide-dependent antimicrobial activities. All biofilm-forming cells treated with Lactobacillus sp. supernatants showed reduced expression of genes involved in exopolysaccharide production, acid tolerance and quorum sensing. Thus, Lactobacillus sp. can inhibit tooth decay by limiting growth and virulence properties of Streptococcus mutans.

The implication of probiotics in the prevention of dental caries

The current oral health crisis, whose causes are varied and complex, necessitates timely oral evaluation and early detection and treatment of oral health problems. Dramatic changes in eating habits and lifestyles are associated with the recent decline in oral health. Probiotics are "good" bacteria that support digestion and a healthy immune system and offer various health benefits to the host. Traditionally, probiotics have been used to improve gut health; the most common uses have historically been as a treatment or prevention of gastrointestinal infections and disease. During the last decade, studies have additionally suggested the intake of probiotics for oral health purposes. Probiotic use provides an effective strategy to combat oral disease, including the development of dental caries and periodontal infection. The aim of this review is to describe the beneficial roles of probiotic bacteria in the oral cavity and the potential mechanisms by which these bacteria exert their effects on oral health.