scholarly journals In vitro Antibacterial Activity of an FDA-Approved H+-ATPase Inhibitor, Bedaquiline, Against Streptococcus mutans in Acidic Milieus

2021 ◽  
Vol 12 ◽  
Author(s):  
Meng Zhang ◽  
Wenqian Yu ◽  
Shujing Zhou ◽  
Bing Zhang ◽  
Edward Chin Man Lo ◽  
...  
Keyword(s):  
Lactic Acid ◽  
Streptococcus Mutans ◽  
Lactic Acid Production ◽  
Extracellular Polysaccharide ◽  
Dependent Manner ◽  
Atpase Inhibitor ◽  
Periodontal Ligament Stem Cells ◽  
Broth Microdilution Method ◽  
Oral Pathogens

BackgroundDental caries is an acid-related disease. Current anti-caries agents mainly focus on the bacteriostatic effect in a neutral environment and do not target acid-resistant microorganisms related to caries in acidic milieus.ObjectivesTo assess the in vitro antibacterial activities of bedaquiline against oral pathogens in acidic milieus.MethodsStreptococcus mutans, Streptococcus sanguinis, and Streptococcus salivarius were used to prepare the mono-/multiple suspension and biofilm. The MIC and IC50 of bedaquiline against S. mutans were determined by the broth microdilution method. Bedaquiline was compared regarding (i) the inhibitory activity in pH 4–7 and at different time points against planktonic and biofilm; (ii) the effect on the production of lactic acid, extracellular polysaccharide, and pH of S. mutans biofilm; (iii) the cytotoxicity effects; and (iv) the activity on H+-ATPase enzyme of S. mutans.ResultsIn pH 5 BHI, 2.5 mg/L (IC50) and 4 mg/L (MIC) of bedaquiline inhibited the proliferation and biofilm generation of S. mutans and Mix in a dose-dependent and time-dependent manner, but it was invalid in a neutral environment. The lactic acid production, polysaccharide production, and pH drop range reduced with the incorporation of bedaquiline in a pH 5 environment. Its inhibitory effect (>56 mg/L) against H+-ATPase enzyme in S. mutans and its non-toxic effect (<10 mg/L) on periodontal ligament stem cells were also confirmed.ConclusionBedaquiline is efficient in inhibiting the proliferation and biofilm generation of S. mutans and other oral pathogens in an acidic environment. Its high targeting property and non-cytotoxicity also promote its clinical application potential in preventing caries. Further investigation of its specific action sites and drug modification are warranted.

Factors Influencing the Competition between Streptococcus oligofermentans and Streptococcus mutans in Dual-Species Biofilms

2017 ◽  
Vol 51 (5) ◽  
pp. 507-514 ◽  
Author(s):  
Xudong Bao ◽  
Jingmei Yang ◽  
J.J. de Soet ◽  
Hongyan Liu ◽  
Xuejun Gao ◽  
...  
Keyword(s):  
Hydrogen Peroxide ◽  
Lactic Acid ◽  
Environmental Factors ◽  
Streptococcus Mutans ◽  
Lactic Acid Production ◽  
Hydrogen Peroxide Production ◽  
Neutral Ph ◽  
Cell Counts ◽  
Ph Conditions

Previous studies have shown that Streptococcus oligofermentans inhibits the growth of cariogenic Streptococcus mutans in biofilms in vitro and is considered a probiotic candidate for caries prevention. This study aimed to examine the effects of various environmental factors on the competition between S. oligofermentans and S. mutans in a dual-species biofilm model. Single or dual S. oligofermentans and S. mutans biofilms were grown in a 96-well active attachment model for 48 h. Several growth conditions were examined in the model, namely: S. oligofermentans was inoculated 24 h before S. mutans or vice versa; the growth medium was supplemented with 0.2% sucrose or 0.4% glucose; biofilms were grown under a constantly neutral pH or pH-cycling condition, which included 8 h of neutral pH and 16 h of pH 5.5. The 48-h biofilms were examined for viable cell counts and lactic acid and hydrogen peroxide production ability. When S. oligofermentans was inoculated first, it clearly inhibited the growth of S. mutans and reduced the biofilm lactic acid production by up to 8-fold through hydrogen peroxide production, independently of sugar supply and pH conditions. When S. mutans was inoculated first, the level of inhibition by S. oligofermentans varied depending on the sugar supply and pH conditions. Thus, the inhibition efficacy of S. oligofermentans against S. mutans in dual-species biofilms is influenced by environmental factors. This study provides practical information on how to maximize the efficacy of S. oligofermentans.

scholarly journals Protective effect of titanium tetrafluoride and silver diamine fluoride on radiation-induced dentin caries in vitro

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Beatriz Martines de Souza ◽  
Mayara Souza Silva ◽  
Aline Silva Braga ◽  
Patrícia Sanches Kerges Bueno ◽  
Paulo Sergio da Silva Santos ◽  
...  
Keyword(s):  
Lactic Acid ◽  
Protective Effect ◽  
Acid Production ◽  
Lactic Acid Production ◽  
Negative Control ◽  
Titanium Tetrafluoride ◽  
Silver Diamine Fluoride ◽  
Dentin Caries ◽  
Radiation Induced

AbstractThis in vitro study evaluated the protective effect of titanium tetrafluoride (TiF4) varnish and silver diamine fluoride (SDF) solution on the radiation-induced dentin caries. Bovine root dentin samples were irradiated (70 Gy) and treated as follows: (6 h): 4% TiF4 varnish; 5.42% NaF varnish; 30% SDF solution; placebo varnish; or untreated (negative control). Microcosm biofilm was produced from human dental biofilm (from patients with head-neck cancer) mixed with McBain saliva for the first 8 h. After 16 h and from day 2 to day 5, McBain saliva (0.2% sucrose) was replaced daily (37 °C, 5% CO2) (biological triplicate). Demineralization was quantified by transverse microradiography (TMR), while biofilm was analyzed by using viability, colony-forming units (CFU) counting and lactic acid production assays. The data were statistically analyzed by ANOVA (p < 0.05). TiF4 and SDF were able to reduce mineral loss compared to placebo and the negative control. TiF4 and SDF significantly reduced the biofilm viability compared to negative control. TiF4 significantly reduced the CFU count of total microorganism, while only SDF affected total streptococci and mutans streptococci counts. The varnishes induced a reduction in lactic acid production compared to the negative control. TiF4 and SDF may be good alternatives to control the development of radiation-induced dentin caries.

scholarly journals Viable and Heat-Killed Probiotic Strains Improve Oral Immunity by Elevating the IgA Concentration in the Oral Mucosa

2021 ◽  
Author(s):  
Wen-Yang Lin ◽  
Yi-Wei Kuo ◽  
Ching-Wei Chen ◽  
Yu-Fen Huang ◽  
Chen-Hung Hsu ◽  
...  
Keyword(s):  
Streptococcus Mutans ◽  
The Body ◽  
Effective Dosage ◽  
Tgf Beta ◽  
Oral Tablet ◽  
Beneficial Effects ◽  
Bifidobacterium Animalis ◽  
Probiotic Strains ◽  
Oral Pathogens

AbstractOral-nasal mucosal immunity plays a crucial role in protecting the body against bacterial and viral invasion. Safe probiotic products have been used to enhance human immunity and oral health. In this study, we verified the beneficial effects of mixed viable probiotic tablets, consisting of Lactobacillus salivarius subsp. salicinius AP-32, Bifidobacterium animalis subsp. lactis CP-9, and Lactobacillus paracasei ET-66, and heat-killed probiotic tablets, consisting of L. salivarius subsp. salicinius AP-32 and L. paracasei ET-66, on oral immunity among 45 healthy participants. Participants were randomly divided into viable probiotic, heat-killed probiotic, and placebo groups. The administration of treatment lasted for 4 weeks. Saliva samples were collected at Weeks 0, 2, 4, and 6, and Lactobacillus, Bifidobacterium and Streptococcus mutans populations and IgA concentration were measured. IgA concentrations, levels of TGF-beta and IL-10 in PBMCs cells were quantified by ELISA method. Results showed that salivary IgA levels were significantly increased on administration of both the viable (119.30 ± 12.63%, ***P < 0.001) and heat-killed (116.78 ± 12.28%, ***P < 0.001) probiotics for 4 weeks. Among three probiotic strains, AP-32 would effectively increase the levels of TGF-beta and IL-10 in PBMCs. The oral pathogen Streptococcus mutans was significantly reduced on viable probiotic tablet administration (49.60 ± 31.01%, ***P < 0.001). The in vitro antibacterial test confirmed that viable probiotics effectively limited the survival rate of oral pathogens. Thus, this clinical pilot study demonstrated that oral probiotic tablets both in viable form or heat-killed form could exert beneficial effects on oral immunity via IL-10, TGB-beta mediated IgA secretion. The effective dosage of viable probiotic content in the oral tablet was 109 CFUs/g and the heat-killed oral tablet was 1 × 1010 cells/g.

scholarly journals The impact of indole-3-lactic acid on immature intestinal innate immunity and development: a transcriptomic analysis

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Wuyang Huang ◽  
Ky Young Cho ◽  
Di Meng ◽  
W. Allan Walker
Keyword(s):  
Lactic Acid ◽  
Mechanistic Model ◽  
Transcriptomic Analysis ◽  
Dependent Manner ◽  
Protective Effects ◽  
Very Preterm Infants ◽  
Anti Inflammatory ◽  
The Impact

AbstractAn excessive intestinal inflammatory response may have a role in the pathogenesis of necrotizing enterocolitis (NEC) in very preterm infants. Indole-3-lactic acid (ILA) of breastmilk tryptophan was identified as the anti-inflammatory metabolite involved in probiotic conditioned media from Bifidobacteria longum subsp infantis. This study aimed to explore the molecular endocytic pathways involved in the protective ILA effect against inflammation. H4 cells, Caco-2 cells, C57BL/6 pup and adult mice were used to compare the anti-inflammatory mechanisms between immature and mature enterocytes in vitro and in vivo. The results show that ILA has pleiotropic protective effects on immature enterocytes including anti-inflammatory, anti-viral, and developmental regulatory potentials in a region-dependent and an age-dependent manner. Quantitative transcriptomic analysis revealed a new mechanistic model in which STAT1 pathways play an important role in IL-1β-induced inflammation and ILA has a regulatory effect on STAT1 pathways. These studies were validated by real-time RT-qPCR and STAT1 inhibitor experiments. Different protective reactions of ILA between immature and mature enterocytes indicated that ILA’s effects are developmentally regulated. These findings may be helpful in preventing NEC for premature infants.

scholarly journals GLUCOSE CONSUMPTION AND LACTIC ACID PRODUCTION BY ERYTHROCYTES FROM DOUBLE-MUSCLED CATTLE

1982 ◽  
Vol 62 (3) ◽  
pp. 751-757 ◽  
Author(s):  
J. A. BASARAB ◽  
R. T. BERG ◽  
J. R. THOMPSON
Keyword(s):  
Lactic Acid ◽  
Key Words ◽  
Acid Production ◽  
Lactic Acid Production ◽  
Age Groups ◽  
Phenotypic Expression ◽  
Glucose Consumption ◽  
Molar Ratio ◽  
Breed Group

The in vitro glucose consumption and lactic acid production by erythrocytes from 20 cattle of a Beef Synthetic (SY) breed group and 25 cattle of a double-muscled (DM) breed group were determined. There were three age groups and two sexes within each breed group. Animals within the DM breed group were categorized as either phenotypically normal- to moderate-muscled (DM carriers) or extreme-muscled (extreme DM) based on the phenotypic expression of the double-muscling trait and on their breeding history. Both DM phenotypes had higher (P < 0.01) erythrocyte glucose consumption and lactic acid production than normal-muscled, noncarrier cattle of the SY breed group. Extreme DM cattle were not different (P > 0.05) in either their erythrocyte glucose consumption or lactic acid production compared with DM carriers. No difference (P > 0.05) due to breed or phenotype was observed in the molar ratio of lactic acid produced to glucose consumed by erythrocytes. These results suggest that carriers of the Double Muscled Syndrome, regardless of phenotypic expression of the double-muscling trait, have a higher rate of erythrocyte glycolysis than normal cattle. Key words: Cattle, double muscled, erythrocyte, glucose, lactic acid

scholarly journals Exopolysaccharides Produced by Streptococcus mutans Glucosyltransferases Modulate the Establishment of Microcolonies within Multispecies Biofilms

2010 ◽  
Vol 192 (12) ◽  
pp. 3024-3032 ◽  
Author(s):  
H. Koo ◽  
J. Xiao ◽  
M. I. Klein ◽  
J. G. Jeon
Keyword(s):  
Streptococcus Mutans ◽  
Extracellular Polysaccharide ◽  
Fluorescence Labeling ◽  
Tooth Surface ◽  
Bacterial Cells ◽  
Actinomyces Naeslundii ◽  
Multispecies Biofilm ◽  
Tooth Surfaces ◽  
Glucan Synthesis

ABSTRACT Streptococcus mutans is a key contributor to the formation of the extracellular polysaccharide (EPS) matrix in dental biofilms. The exopolysaccharides, which are mostly glucans synthesized by streptococcal glucosyltransferases (Gtfs), provide binding sites that promote accumulation of microorganisms on the tooth surface and further establishment of pathogenic biofilms. This study explored (i) the role of S. mutans Gtfs in the development of the EPS matrix and microcolonies in biofilms, (ii) the influence of exopolysaccharides on formation of microcolonies, and (iii) establishment of S. mutans in a multispecies biofilm in vitro using a novel fluorescence labeling technique. Our data show that the ability of S. mutans strains defective in the gtfB gene or the gtfB and gtfC genes to form microcolonies on saliva-coated hydroxyapatite surfaces was markedly disrupted. However, deletion of both gtfB (associated with insoluble glucan synthesis) and gtfC (associated with insoluble and soluble glucan synthesis) is required for the maximum reduction in EPS matrix and biofilm formation. S. mutans grown with sucrose in the presence of Streptococcus oralis and Actinomyces naeslundii steadily formed exopolysaccharides, which allowed the initial clustering of bacterial cells and further development into highly structured microcolonies. Concomitantly, S. mutans became the major species in the mature biofilm. Neither the EPS matrix nor microcolonies were formed in the presence of glucose in the multispecies biofilm. Our data show that GtfB and GtfC are essential for establishment of the EPS matrix, but GtfB appears to be responsible for formation of microcolonies by S. mutans; these Gtf-mediated processes may enhance the competitiveness of S. mutans in the multispecies environment in biofilms on tooth surfaces.

scholarly journals Lactic Acid Bacteria Co-Encapsulated with Lactobionic Acid: Probiotic Viability during In Vitro Digestion

2021 ◽  
Vol 11 (23) ◽  
pp. 11404
Author(s):  
Sara Sáez-Orviz ◽  
Francesca Passannanti ◽  
Marianna Gallo ◽  
Rosa Colucci Cante ◽  
Federica Nigro ◽  
...  
Keyword(s):  
Lactic Acid ◽  
Saline Solution ◽  
Lactic Acid Production ◽  
In Vitro Digestion ◽  
Lactobionic Acid ◽  
Different Types ◽  
Stability Time ◽  
Over Time ◽  
Improve Health

Synbiotic products are a type of functional food with great potential due to consumer interest in foods that improve health and/or reduce the risk of certain diseases. In this study, synbiotic macrocapsules were developed using Lactobacillus paracasei CBA L74 as probiotic and lactobionic acid (LBA) as prebiotic. Firstly, the probiotic was proven to be able to use LBA as the only substrate source checking their growth and lactic acid production. Then, four different types of capsules were produced using sodium alginate as matrix and different hardener solutions (CaCl2 and chitosan). The macrocapsules were characterised regarding their strength, and the best performing ones were used for further analysis. In order to obtain a synbiotic capsule characterized by a longer stability time due to low water activity, the capsules were dried using freeze and thermal drying. Successively, to revitalize the microorganisms, the capsules were rehydrated in two different media (saline solution and yogurt), subjected to simulated in vitro digestion tests and visually characterised. In addition, their viability over time was assessed. As a result, L. paracasei was able to grow using LBA as the only source of carbon with better production of lactic acid for prolonged periods. The more resistant freeze- and thermal-dried capsules showed differences in rehydration kinetics, and visual changes were also observed. In simulated in vitro digestion tests, capsules rehydrated in yogurt showed the best results in terms of survival. Regarding their viability over time, the importance of the use of chitosan was noted.

Carbohydrate Metabolism of Chick Fibroblasts in Vitro

1942 ◽  
Vol 18 (3) ◽  
pp. 237-256
Author(s):  
E. N. WILLMER
Keyword(s):  
Lactic Acid ◽  
Carbohydrate Metabolism ◽  
Acid Production ◽  
Lactic Acid Production ◽  
High Growth ◽  
Glucose Consumption ◽  
High Growth Rate ◽  
Absolute Correlation ◽  
Heart Cultures

1. The glucose consumption of osteoblasts growing in a medium of plasma and embryo juice has been compared with that of the same cells in plasma and Tyrode medium. Embryo juice causes an initial increased glucose consumption which later falls below the level characteristic of a Tyrode-plasma medium. 2. A modification of a method of measuring the nucleoprotein phosphorus content of tissue cultures is described and among other data obtained the changes which occur in this figure have been noted for fourth passage chick osteoblast cultures and for fresh heart explants during the first 4 days of culture in media of plasma and Tyrode and of plasma and embryo juice. 3. The figures for nucleoprotein content have been correlated with those for glucose consumption and lactic acid production and pronounced differences have been observed in the behaviour of the two types of tissue. The possible significance of the findings is discussed. 4. There is no absolute correlation between high growth rate and high sugar consumption or lactic acid production. 5. The data discussed are consistent with the idea that an increased protein metabolism, and a decreased carbohydrate metabolism result from the addition of embryo juice to osteoblast cultures. Embryo juice has no detectable effects on the carbohydrate metabolism of fresh heart cultures.

scholarly journals Low-Carbohydrate Tolerant LAB Strains Identified from Rumen Fluid: Investigation of Probiotic Activity and Legume Silage Fermentation

2020 ◽  
Vol 8 (7) ◽  
pp. 1044
Author(s):  
Palaniselvam Kuppusamy ◽  
Dahye Kim ◽  
Ilavenil Soundharrajan ◽  
Hyung Soo Park ◽  
Jeong Sung Jung ◽  
...  
Keyword(s):  
Lactic Acid ◽  
Rumen Fluid ◽  
Lactic Acid Production ◽  
Antagonistic Activity ◽  
Probiotic Properties ◽  
Trifolium Incarnatum ◽  
Crimson Clover ◽  
Silage Fermentation ◽  
Low Carbohydrate

The objective of this study was to isolate and characterize lactic acid bacteria (LAB) with low carbohydrate tolerance from rumen fluid and to elucidate their probiotic properties and the quality of fermentation of Medicago sativa L. and Trifolium incarnatum L. silage in vitro. We isolated 39 LAB strains and screened for growth in MRS broth and a low-carbohydrate supplemented medium; among them, two strains, Lactiplantibacillus plantarum (Lactobacillus plantarum) RJ1 and Pediococcus pentosaceus S22, were able to grow faster in the low-carbohydrate medium. Both strains have promising probiotic characteristics including antagonistic activity against P. aeruginosa, E. coli, S. aureus, and E. faecalis; the ability to survive in simulated gastric-intestinal fluid; tolerance to bile salts; and proteolytic activity. Furthermore, an in vitro silage fermentation study revealed that alfalfa and crimson clover silage inoculated with RJ1 and S22 showed significantly decreased pH and an increased LAB population at the end of fermentation. Also, the highest lactic acid production was noted (p < 0.05) in LAB-inoculated silage vs. non-inoculated legume silage at high moisture. Overall, the data suggest that RJ1 and S22 could be effective strains for fermentation of legume silage.

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