Growth inhibition of Streptococcus mutans by cellular extracts of human intestinal lactic acid bacteria

Antimicrobial activity of dominant Ligilactobacillus animalis strains in healthy canine feces and their probiotic potential

The number of companion animals living with humans has continually increased over the last few decades, and so has the interest of owners and stakeholders in the animal food and probiotics industry. Currently, the probiotic bacteria added to the feed of companion animals predominantly originate from the lactic acid bacteria (LAB) used for humans; however, there are differences between the microbiota of humans and that of their companion animals. This study aimed to determine the dominant LAB in dog feces and investigate their functional properties. Ligilactobacillus animalis (formerly called Lactobacillus animalis) was identified as the dominant lactic acid bacterium in dog feces. It displayed various inhibitory effects against pathogenic and enteropathogenic bacteria. This finding suggests that Ligilactobacillus animalis can potentially be used in novel probiotics or as a food additive for dogs.

Comparison of efficacy of probiotics versus tetracycline fibers as adjuvants to scaling and root planing

Context:

Both gingivitis and periodontitis are due to the detrimental effects of the microbe-laden biofilm. The mainstay of periodontal treatment is, therefore, the disruption of this biofilm by scaling and root planing (SRP). Other treatment protocols such as systemic antimicrobials have been administered as adjuvants after scaling and root planning. However, due to antimicrobial resistance, as well as a shift of the flora from a symbiotic to a dysbiotic one, this mode of treatment has its shortcomings. Thus, local drug delivery has gained prominence as a therapeutic tool.

Aims:

The aim of this study is to compare the efficacy of subgingivally delivered probiotics as a monotherapy, in combination with tetracycline fibers, and tetracycline fibers alone after SRP.

Settings and Design:

This study was a parallel arm, randomized clinical and microbiological study. Thirty patients with chronic periodontitis aged between 20 and 50 years were selected from the outpatient ward of a tertiary referral care hospital in Hyderabad and equally divided into three groups.

Materials and Methods:

This study was conducted from January 2017 to February 2017 and ethical clearance was obtained from the institutional ethical committee.

Statistical Analysis Used:

Mean values and standard deviations were calculated for Plaque Index, Sulcular Bleeding Index (SBI), probing depth (PD), and microbial colony-forming units, for all the three groups at different time intervals. Paired “t-test” was used for intragroup comparison and Student's “t-test” for intergroup comparison. Results were regarded as statistically significant when P < 0.05.

Results:

Intragroup comparison yielded significant improvement in all the variables (P < 0.0001). However, intergroup comparison showed statistically significant differences pertaining to the PD (P < 0.001) and SBI only (P < 0.001), between Group A and Group B and Group B and Group C respectively.

Conclusions:

Group A and Group C showed better results than Group B.

Evaluation of the efficacy of probiotics in plaque reduction and gingival health maintenance among school children - A Randomized Control Trial

BACKGROUND

Probiotics are live micro-organisms that when administered in adequate amounts confer health benefits upon the host. The impact of probiotics on oral health is relatively new with lots of research going on; the area of probiotics and periodontal disease is still in its infancy. The aim of the present trial was to evaluate the efficacy of the probiotics in plaque reduction among school children.

MATERIALS & METHODS

This is a randomized, double-blind, placebo controlled parallel design study involving 216 school children (aged 14 - 17 years): 108 as experimental subjects and 108 as controls. Complete oral prophylaxes were performed for both the control group and experimental group. The pre-intervention plaque index and gingival index were recorded one week after the prophylaxis for both groups as the baseline data. The study subjects (Group A) included curd in their daily diet for 30 days, while the control subjects (Group B) excluded curd in their diet for 30 days. The post intervention plaque index and gingival index were recorded again and statistically compared with the baseline data.

RESULTS

the intervention group (Group A) was found to have statistically significant reduction in plaque when compared to that of the control group with p <0.001 and there was no significant improvement in gingival health.

CONCLUSION

A short-term daily ingestion of probiotics delivered via curd in diet reduced the levels of plaque. Hence if it can be promoted in the regular diet, it would help in improving the oral health among school children. How to cite this article: Karuppaiah RM, Shankar S, Raj SK, Ramesh K, Prakash R, Kruthika M. Evaluation of the efficacy of probiotics in plaque reduction and gingival health maintenance among school children - A Randomized Control Trial. J Int Oral Health 2013; 5(5):33-7.

Inhibitory effect of Lactobacillus reuteri on periodontopathic and cariogenic bacteria

The interaction between Lactobacillus reuteri, a probiotic bacterium, and oral pathogenic bacteria have not been studied adequately. This study examined the effects of L. reuteri on the proliferation of periodontopathic bacteria including Aggregatibacter actinomycetemcomitans, Fusobacterium nucleatum, Porphyromonas gingivalis, and Tannerella forsythia, and on the formation of Streptococcus mutans biofilms. Human-derived L. reuteri strains (KCTC 3594 and KCTC 3678) and rat-derived L. reuteri KCTC 3679 were used. All strains exhibited significant inhibitory effects on the growth of periodontopathic bacteria and the formation of S. mutans biofilms. These antibacterial activities of L. reuteri were attributed to the production of organic acids, hydrogen peroxide, and a bacteriocin-like compound. Reuterin, an antimicrobial factor, was produced only by L. reuteri KCTC 3594. In addition, L. reuteri inhibited the production of methyl mercaptan by F. nucleatum and P. gingivalis. Overall, these results suggest that L. reuteri may be useful as a probiotic agent for improving oral health.

Antimicrobial activity of Bifidobacterium spp. isolated from healthy adult Koreans against cariogenic microflora

OBJECTIVE

Dental caries is the main common infectious disease in the human oral cavity. Streptococcus mutans and Streptococcus sobrinus were reported to be the most important etiological factors in human dental caries. Thus, we examined the inhibitory effects of Bifidobacterium spp. cells and culture supernatants against S. mutans and S. sobrinus, including Streptococcus gordonii, and Aggregatibacter actinomycetemcomitans, which is associated with periodontal disease.

METHODS

Mutans streptococci or A. actinomycetemcomitans and lactic acid bacteria (LAB) were mixed in 1:1 ratio and then incubated for 90 min at 37°C. After the incubation, the viability of mutans streptococci or A. actinomycetemcomitans was determined by plate count technique. We also investigated the morphological changes of S. mutans treated with LAB using scanning electron microscopy (SEM).

RESULTS

In vitro viability of S. mutans, S. sobrinus, S. gordonii, and A. actinomycetemcomitans was affected by human intestinal LAB identified as Bifidobacterium adolescentis SPM1005 and Bifidobacterium longum SPM1207. Especially, B. adolescentis SPM1005 cells at 1.0 × 10(8) CFU had a strong growth-inhibiting effect against S. mutans and induced a 64% loss of its viability (p<0.05). In addition, swollen and disrupted S. mutans were observed after incubation with B. adolescentis SPM1005. However, the culture supernatant of this strain did not show such inhibitory activity.

CONCLUSION

B. adolescentis SPM1005 cells decreased the growth of S. mutans, which is a risk factor for dental caries. Therefore, we suggest that this Bifidobacterium strain may be a useful probiotic microorganism for prevention of dental caries that does not have adverse effects.

Bovine milk fermented with Lactobacillus rhamnosus L8020 decreases the oral carriage of mutans streptococci and the burden of periodontal pathogens

AIM

  The aim of this study was to find the oral isolate of lactobacilli, which has the potential to inhibit either periodontal, cariogenic, or fungal pathogens in vitro, and to examine the effects of bovine milk fermented with the isolate on the oral carriage of cariogenic and periodontal pathogens.

METHODS

  The inhibitory effects of the supernatant of Man-Rogosa-Sharpe broth, in which each of 42 oral isolates of lactobacilli grown, was examined. One isolate, Lactobacillus rhamnosus L8020, that showed the potential to inhibit either periodontal, cariogenic, or fungal pathogens in vitro, was used to examine the effects of fermented milk on the oral carriage of cariogenic and periodontal pathogens, which was examined by a placebo-controlled and cohort trial using 50 participants.

RESULTS

  Edible yogurt containing Lactobacillus rhamnosus L8020 significantly reduced the oral carriage of mutans streptococci (P < 0.01) and four periodontal pathogens examined: Porphyromonas gingivalis, Prevotella intermedia, Tannerella forsythia, and Fusobacterium spp. (P < 0.01), but the phenomenon were not observed with the placebo yogurt (P > 0.05).

CONCLUSION

  These results suggest that yogurt with Lactobacillus rhamnosus L8020 could reduce the risk of dental caries and periodontal disease.

Probiotic Lactobacillus paracasei effect on cariogenic bacterial flora

Lactobacillus paracasei has been demonstrated to inhibit the growth of many pathogenic microbes such as Streptococcus mutans, in vitro. However, its clinical application remains unclear. Here, we examined whether a novel probiotic L. paracasei GMNL-33 may reduce the caries-associated salivary microbial counts in healthy adults. Seventy-eight subjects (aged 20 to 26) had completed this double-blinded, randomized, placebo-controlled study. A probiotic/test (n = 42) and a control group (n = 36) took a L. paracasei GMNL-33 and a placebo oral tablet three times per day for 2 weeks, respectively. Bacterial counts of salivary S. mutans, lactobacilli, and salivary buffer capacity were measured with chair-side kits at the beginning (T1), the completion (T2) of medication, and 2 weeks after medication (T3). The results did not show differences in the counts of S. mutans and lactobacilli between probiotic and control groups at T1, T2, and T3. Nevertheless, within the probiotic group, an interesting probiotic effect was noticed. Between T1 and T2, no inhibitory effect against S. mutans was observed. However, a significant count reduction in the salivary S. mutans was detected between T2 and T3 (p = 0.016). Thus, a 2-week period of medication via oral administration route may be needed for L. paracasei GMNL-33 to be effective in the probiotic action.

Final pH affects the interference capacity of naturally occurring oral Lactobacillus strains against mutans streptococci

OBJECTIVES

To establish the effects of three factors: previous caries experience; colonization of Streptococcus mutans; and final pH on autologous lactobacilli-mediated inhibition against a panel of mutans streptococci in young subjects with different caries experiences.

DESIGN

The inhibition capacity was determined by the use of the agar overlay method and the final pH in culture medium was measured after 20 h. Using a logistic regression model, the risk of having an incomplete lactobacilli-mediated inhibition was calculated.

RESULTS

All three factors significantly influenced the interference outcome in the order; final pH of the Lactobacillus strains, oral colonization of autologous S. mutans and caries experience. A high risk occurred at a lower pH and at a wider pH range for individuals with previous caries experience and autologous colonization of S. mutans compared with caries-free subjects who were not colonized. At a final pH of 4.0, this risk was approximately eight times higher than that of the latter group. Two mutans Streptococcus strains in the test panel demonstrated high individual predictive values of inhibition mediated by oral lactobacilli.

CONCLUSIONS

Generation of a low pH either directly via organic acid production and/or production of bacteriocins or metabolites at a low pH may promote mutans Streptococcus growth inhibition, in vitro. Furthermore, a shift of pH range for the risk of incomplete inhibition of mutans streptococci suggests a less effective inhibition at a wider pH range for naturally occurring lactobacilli from individuals with earlier caries experience containing own S. mutans.

Probiotics and oral health effects in children

BACKGROUND

Probiotics are living micro-organisms added to food which beneficially affect the host by improving its intestinal microbial balance.

OBJECTIVE

This paper aims to present a general background on probiotics and its health effects in children, and to examine the evidence for oral colonization and the possible impact on oral health in children and young adults.

METHODS

For delivery and general health effects, recent systematic reviews, meta-analyses, and other relevant papers were used. Concerning oral installation and oral effects, a broad search for publications in English was conducted through February 2007 in PubMed. Studies describing an installation or intervention trial in humans with a controlled design and an oral endpoint measure were considered. Fourteen papers with dental focus were identified, of which two were narrative reviews.

RESULTS

Only one study of dental interest was conducted in children. Four papers dealt with oral installation of probiotic bacteria, and although detectable levels were found in saliva shortly after intake, the studies failed to demonstrate a long-term installation. Seven papers evaluated the effect of lactobacilli- or bifidobacteria-derived probiotics on the salivary levels of caries-associated bacteria in placebo-controlled designs. All but one reported a hampering effect on mutans streptococci and/or yeast. The single study carried out in early childhood reported a significant caries reduction in 3- to 4-year-old children after 7 months of daily consumption of probiotic milk.

CONCLUSION

Bacteriotheraphy in the form of probiotic bacteria with an inhibitory effect on oral pathogens is a promising concept, especially in childhood, but this may not necessarily lead to improved oral health. Further placebo controlled trials that assess carefully selected and defined probiotic strains using standardized outcomes are needed before any clinical recommendations can be made.

Lactobacillus reuteri in bovine milk fermented decreases the oral carriage of mutans streptococci

The effect of Lactobacillus reuteri against one of the major cariogenic organism, Streptococcus mutans, was studied. Yogurt products containing L.reuteri showed a significant growth inhibitory effect against S. mutans, whilst yoghurts with lactobaccilli other than L. reuteri did not show such inhibition. Further, double-blind, placebo-controlled trial demonstrated that consuming yogurt with L. reuteri significantly reduced the oral carriage of mutans streptococci, compared with the placebo yogurt.

Isolation and characterization of Lactobacillus species inhibiting the formation of Streptococcus mutans biofilm

Oral bacterium S11 was isolated from the saliva of young children without dental caries and with little or no visible supragingival plaque. The S11 strain showed 99.5% similarity with Lactobacillus fermentum, and was identified on the basis of biochemical characteristics and a 16S rDNA sequence. S11 strain and its culture supernatant significantly inhibited the formation of the insoluble glucan produced by Streptococcus mutans Ingbritt. S11 did not affect the multiplication of S. mutans Ingbritt, but the adherence of S. mutans Ingbritt onto cuvette walls was inhibited completely.

Effects of probiotic bacteria on diarrhea, lipid metabolism, and carcinogenesis: a review of papers published between 1988 and 1998

We reviewed the evidence from human intervention studies for the health effects of probiotic bacteria, ie, live bacteria that survive passage through the gastrointestinal tract and have beneficial effects on the host. Of the 49 studies reviewed, 26 dealt with the prevention or treatment of diarrheal disease, 9 with the prevention of cancer or of the formation of carcinogens, 7 with the lowering of serum cholesterol, and 7 with the stimulation of the immune system. The most widely studied probiotic bacteria were Lactobacillus GG (22 studies), Lactobacillus acidophilus (16 studies), Bifidobacterium bifidum (6 studies), and Enterococcus faecium (7 studies). Intake of Lactobacillus GG consistently shortened the diarrheal phase of rotavirus infection by 1 d. However, evidence for the prevention by Lactobacillus GG and other probiotics of diarrhea due to viral or bacterial infections was less strong. Effects of probiotics on the immune system are inconclusive because of the variety of outcome variables reported. Cholesterol lowering by L. acidophilus was shown in some but not all studies; cholesterol lowering by E. faecium seems to be transient. Two studies of one research group showed a smaller recurrence of bladder tumors in patients after treatment with Lactobacillus casei; these results await confirmation. The production of mutagens after a meal might be reduced by the concomitant intake of probiotics, but the relevance of this finding is unclear. In conclusion, consumption of foods containing Lactobacillus GG may shorten the course of rotavirus infection. Other health effects of probiotic bacteria have not been well established. Well-designed placebo-controlled studies with validated outcome variables are needed to determine the health effects of probiotics.

Effect of Lactobacillus rhamnosus strain GG (ATCC 53103) on the growth of Streptococcus sobrinus in vitro

Lactobacillus GG, a recently characterized L. rhamnosus GG strain (ATCC 53103), has been shown to exert inhibitory activity against a variety of bacterial species, including streptococci. We isolated and studied the effect of the inhibitory substance of Lactobacillus GG on some oral streptococci. The inhibitory activity of the isolated substance was weak, but some growth inhibition was observed in Streptococcus sobrinus pretreated with the substance in comparison with untreated controls. Zones of growth inhibition on agar plates were apparent only at pH values below 5, indicating that the inhibitory activity was restricted to a low pH range. Growth curve experiments showed a statistically significant inhibition between series with and without the isolated substance (P < 0.05). The ultrastructure of S. sobrinus was not affected when treated with the inhibitory substance. The Lactobacillus GG itself did not ferment sucrose. The results offer interesting perspectives for future research focusing on the protective function of normal flora and in the attempt to replace harmful bacterial species in oral microflora with less harmful ones.