Isolates Of Streptococcus Mutans Research Articles

Comparative Assessment of Antimicrobial Activity of Propolis and Chlorhexidine on Salivary Isolates of Candida albicans and Streptococcus mutans in Children with Severe Early Childhood Caries: An In Vitro Study.

Streptococcus mutans and Candida albicans are the chief microbes associated with severe early childhood caries (S-ECC). Diverse antimicrobial agents are widely used to prevent ECC, and a quest for newer natural products has been on the rise in the recent past. To estimate the antimicrobial activity of propolis with chlorhexidine on salivary specimens from children with S-ECC in vitro. A total of 60 children with S-ECC were designated. Salivary samples of 30 children (group I) were inoculated onto mitis salivarius agar (MSA) to isolate S. mutans. Another 30 samples (group II) were inoculated on sabouraud's dextrose agar and subcultured on HiCrome Candida differential agar to isolate C. albicans. Sensitivity testing for 0.2% chlorhexidine and 10% propolis extract was done using the agar well diffusion technique using Mueller-Hinton agar medium. The antimicrobial effect was evaluated by calculating the diameter of the zone of inhibition surrounding the well. All saliva samples collected from groups I and II showed growth of S. mutans and C. albicans, respectively. All cultured microbes were sensitive to 0.2% chlorhexidine and 10% propolis extract. The mean inhibition zone for S. mutans with chlorhexidine was 14.57 ± 0.63 mm, and with propolis, 11.93 ± 0.52 mm. The mean zone of inhibition for C. albicans with chlorhexidine was 12.83 ± 0.59 mm, and with propolis, 9.50 ± 0.73 mm. Chlorhexidine consistently showed statistically significantly larger zones of inhibition and hence appeared to be a more potent antimicrobial agent than propolis extract for both S. mutans and C. albicans. However, propolis has irrefutable action against both S. mutans and C. albicans. Propolis may be an acceptable substitute for chlorhexidine for long-term use as it has demonstrated antimicrobial activity and fewer side effects. Hence, this Association of Physicians of India herbal drug can be incorporated into mouthwashes and toothpaste to reduce microbial counts. Kodgi V, Shetty P, Thimmaiah C, et al. Comparative Assessment of Antimicrobial Activity of Propolis and Chlorhexidine on Salivary Isolates of Candida albicans and Streptococcus mutans in Children with Severe Early Childhood Caries: An In Vitro Study. Int J Clin Pediatr Dent 2024;17(5):591-595.

Probiotics, A New Frontier in Oral Health: Unraveling the Efficacy of Probiotic Metabolites vs. Chlorhexidine on Streptococcus mutans in Dental Plaque

The battle against dental caries has long been fought with conventional antimicrobial agents, with Chlorhexidine leading the charge. However, recent research has delved into the potential of probiotic metabolites as an alternative or adjunctive therapy in the quest for better oral health. In this editorial, we explore the emerging evidence surrounding the efficacy of probiotic metabolites compared to Chlorhexidine, specifically targetting local clinical isolates of Streptococcus mutans within dental plaque. Streptococcus mutans, a key player in the formation of dental plaque, has been a prime target for antimicrobial interventions due to its significant role in tooth decay. Chlorhexidine, a widely used antiseptic, has been a stalwart in dental care. However, its efficacy and potential side effects have prompted researchers to seek alternative approaches. Probiotic metabolites, byproducts of beneficial bacteria, have emerged as a promising avenue, with studies suggesting their ability to promote oral health by modulating the microbial balance.1 Recent studies have begun to unravel the intricate interactions between probiotic metabolites and Streptococcus mutans. These investigations have not only explored the direct antimicrobial effects but also the potential for probiotics to influence the overall microbial environment in the oral cavity. The comparison with Chlorhexidine, a gold standard in dental care, adds depth to our understanding of these alternative therapies.2 The evidence supporting the efficacy of probiotic metabolites in controlling Streptococcus mutans is not only encouraging but also challenges the status quo. A study by Gong SG et al. (2023) demonstrated that probiotic metabolites significantly reduced the growth of Streptococcus mutans in vitro, highlighting their potential as a potent antimicrobial agent.3 This finding is particularly promising given the increasing concerns about antibiotic resistance and the need for sustainable alternatives.
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Antibiofilm and Antibacterial Properties of Herbal Extracts as Alternatives to Current Treatment Approaches: A Narrative Review

Bacterial biofilm formation poses significant challenges in the healthcare sector due to increased antibiotic resistance and persistent infections. This literature review explores the potential of some herbs and their extracts as alternative approaches to combat biofilm formation and multidrug-resistant bacteria. A detailed literature search was conducted across databases for published studies till 2023, to identify studies on medicinal plants' anti-biofilm and antibacterial properties. Key compounds within plant extracts showing anti-biofilm activity and their mechanisms of action were highlighted. A combination of keywords, MeSH terms, and Boolean operators were used to formulate the search strategy. Numerous studies demonstrated the efficacy of medicinal plants in inhibiting biofilm formation and combating multidrug-resistant bacteria. Active compounds such as benzyl (6Z,9Z,12Z)-6,9,12-octadecatrienoate, 3-benzyloxy-1-nitro-butan-2-ol, Pyridine, 3-(1-methyl-2-pyrrolidinyl)-(S), and others exhibited anti-biofilm and antibacterial potential. Extracts from Berginia ciliata, Clematis grata, and Clematis viticella showed over 80% inhibition of biofilm formation, while mango leaf extracts interfered with quorum sensing mechanisms in Pseudomonas aeruginosa PAO1. Salvadora persica extracts displayed significant biofilm inhibition against cariogenic Streptococcus mutans isolates. Medicinal plants and their extracts hold promise as alternative strategies to combat bacterial biofilms and multidrug-resistant bacteria. The identification of active compounds provides opportunities for further research and drug development. Molecular docking studies are crucial for understanding the molecular interactions between these compounds and bacterial targets, guiding the design of effective antibacterial agents based on natural compounds. Further research, including preclinical and clinical trials, is essential to validate the safety and efficacy of these extracts and their compounds for practical application in healthcare.

Comparison of the Antibacterial Efficacy of Bamboo Shoot Ethanol Extract With Chlorhexidine Mouth Rinse Against Salivary Streptococcus mutans and Lactobacillus acidophilus: An Ex Vivo Study.

Background Dental caries is the most prevalent polymicrobial oral infectious disease tormenting individuals' healthy lifestyles and presents a significant public health problem. The objective of this study was to evaluate and compare the antibacterial properties of different concentrations of bamboo shoot ethanol extract with chlorhexidine mouth rinse on isolates of salivary Streptococcus mutans (S. mutans) and Lactobacillus acidophilus (L. acidophilus). Materials and methods Non-stimulated salivary samples from 30 young adults were treated ex vivo with bamboo shoot ethanolic extract at concentrations of 30 µg/ml, 40 µg/ml, 50 µg/ml, and 60 µg/ml. The colony-forming units were quantified by measuring the number of viable bacterial cells. Inhibition zones were evaluated using the agar diffusion method. One-way ANOVA and post-hoc test were used to analyze the significant difference between variables using SPSS version 22.0 (IBM Corp., Armonk, NY). Results The mean zone of inhibition with bamboo shoot ethanolic extract against salivary S. mutans (23.00 ± 0.816) and L. acidophilus (22.00 ± 0.816) total counts was closest to the control chlorhexidine (S. mutans =22.00 ± 0.876 and L. acidophilus =21.10 ± 0.876). A greater activity against S. mutans and L. acidophilus is seen in the zone of inhibition of the 60 µg/ml experimental concentration of bamboo shoot ethanolic extract, with a significant difference in the disc diffusion assay. Conclusion The treatment with bamboo shoot extract was equivalent effective in the mentioned bacterial species. Clinical relevance It can be assured that preventive measures like mouth rinse and dentifrices compromising bamboo shoots, a potential dental biomaterial, would be optimistic agents for caries control, including the cariostatic effect.

The Effect of Diode Laser on Viability and Antibiotic Sensitivity of Streptococcus mutans Isolated From Dental Caries

Streptococcus mutans is one of the major cariogenic microbial flora. In an attempt to determine the mutagenic effect of diode laser on the viability and antibiotic sensitivity of this bacteria; A total of 30 samples were collected from dental caries. The isolates were identified using by conventional identification methods and confirmed using VITEK2 system. Twenty-one isolates were recorded as Streptococcus spp and ten of them were identified as Streptococcus mutans. Antibiotic susceptibility profile for Streptococcus mutans isolates against ten antibiotics was tested. The results revealed that all the isolates were resistant to cefixime and cephalothin, nine of them were resistant to erythromycin, ampicillin, and nalidixic acid, seven isolates were resistant to tetracycline and bacitracin, whereas all isolates were sensitive to chloramphenicol, ciprofloxacin and gentamycin. The effect of the diode laser on the isolates (S5 and S10) was tested at different time intervals (1, 2, 5, and 10) min. The viability of Streptococcus mutans isolates was affected by the obvious change in the behaviour of the bacteria from resistance to sensitivity after Laser exposure

Antibiofilm Efficacy of Mimosa pudica against Clinical Isolates of Streptococcus mutans as a Mouthrinse

Antibiofilm Efficacy of Mimosa pudica against Clinical Isolates of Streptococcus mutans as a Mouthrinse

Genomic and phenotypic characterization of Streptococcus mutans isolates suggests key gene clusters in regulating its interaction with Streptococcus gordonii.

Streptococcus mutans (S. mutans) is one of the primary pathogens responsible for dental caries. Streptococcus gordonii (S. gordonii) is one of the early colonizers of dental plaque and can compete with S. mutans for growth. In the present analysis, we explored key target genes against S. gordonii in S. mutans using 80 S. mutans clinical isolates with varying capabilities against S. gordonii. A principal coordinate analysis revealed significant genetic diversity differences between antagonistic and non-antagonistic groups. Genomic comparisons revealed 33 and 61 genes that were, respectively, positively and negatively correlated with S. mutans against S. gordonii, with RNA-sequencing (RNA-seq) highlighting 11 and 43 genes that were, respectively, upregulated and downregulated in the antagonistic group. Through a combination of these results and antiSMASH analysis, we selected 16 genes for qRT-PCR validation in which the expression levels of SMU_137 (malate dehydrogenase, mleS), SMU_138 (malate permease, mleP), SMU_139 (oxalate decarboxylase, oxdC), and SMU_140 (glutathione reductase) were consistent with RNA-seq results. SMU_1315c-1317c (SMU_1315c transport-related gene) and SMU_1908c-1909c were, respectively, downregulated and upregulated in the antagonistic group. The expression patterns of adjacent genes were closely related, with correlation coefficient values greater than 0.9. These data reveal new targets (SMU_137–140, SMU_1315c-1317c, and SMU_1908c-1909c) for investigating the critical gene clusters against S. gordonii in S. mutans clinical isolates.

Antibacterial activity of Solanum macrocarpon against clinically derived isolates of Streptococcus mutans from patients attending university of Maiduguri teaching hospital: Implantation of correlation analysis prior to mathematical and computational appro

Plants have been employed as herbal medicines in many parts of the world, and this tend to gain attention as complementary or alternative to modern medicines. This study is aimed to assess the antibacterial activity ofSolanum macrocarpon against Streptococcus mutans. Standard microbiological and biochemical techniques were used to isolates and identify Streptococcus mutans. The Distilled water, Ethanol, Methanol extraction were performed on different part of Solanum macrocarpon and tested for antibacterial activity using the Agar well diffusion method. All the extracts inhibit the growth of Streptococcus mutans except distilled water extract with no or little effect. The results also showed an increase in antibacterial activity with increase in concentration21 mm at 100% concentration to 4 mm of the crude extracts. This study therefore revealed that Solanum macrocarponextract demonstrated greet inhibitory effect on the test organism. Thus, the result provides a basis for the traditional use of Solanum macrocarpon in cleaning teeth and toothache treatment.

Characteristics of Clinical Isolates of Streptococcus mutans

Dental caries is an infectious disease which remains a significant health problem all over the world. The purpose of the study was to characterise a collection of 60 clinical isolates of S. mutans from adults’ and children’s dental plaque (natural biofilm). The paper describes the process of isolation, identification, analysis of biofilm formation and collection testing for the presence of 13 two-component systems (TCS) identified earlier in reference strain ATCC 700610 (UA159). In the case of S. mutans strains, plaque formation is specifically influenced by binary systems. All isolated strains of S. mutans form biofilm at high levels and possess a set of 26 genes forming TSC binary systems, which have an important role in plaque formation.

Ca19Zn2(PO4)14 Nanoparticles: Synthesis, characterization and its effect on the colonization of Streptococcus mutans on tooth surface

The main cause of tooth decay is the biofilm formation of Streptococcus mutans. This study aimed to investigate the effect of the zinc oxide nanoparticles (ZnO NPs), hydroxyapatite nanoparticles (Ca10(PO4)6(OH)2) (HAP NPs), zinc oxide/hydroxyapatite nanocomposites (ZnO/HAP NCs), and Zn-substituted hydroxyapatite nanoparticles (Ca19Zn2(PO4)14 NPs) on the growth and biofilm formation, bacterial adherence, and the expression of ftf and gtf genes in Streptococcus mutans. The nanostructures were prepared via simple and fast co-precipitation route. Twelve isolates of Streptococcus mutans collected from children with dental caries referred to the dental clinic of Kashan University of Medical Sciences. All S. mutans isolates were susceptible to Ampicillin. The mean MIC for ZnO NPs, HAP NPs, Ca19Zn2(PO4)14, and ZnO/HAP NCs were 118, 260, 70.6, and 994 µg/mL, respectively. All prepared nanostructures significantly reduced biofilm formation at MIC and sub-MIC concentrations (p < 0.01). In biofilm and cell culture treated with nanoparticles, the expression of ftf and gtfC genes decreased. Results were shown that IC50 for the Ca19Zn2(PO4)14 was 8.5, and for non-toxic concentration, was 0.065 µg/mL. The attachment rate to the denture surface and HGF1 cell line treated with the Ca19Zn2(PO4)14 NPs has decreased. The results showed that the Ca19Zn2(PO4)14 NPs has a better effect than the ZnO/HAP NCs. It can therefore be used as a coating on dental surfaces. Investigation of Ca19Zn2(PO4)14 NPs form for covering dental teeth surface recommended in future study.

The Antibacterial Activity of Nanosilver Coupled Edible Plant Extracts Against Streptococcus mutans, the Cause of Dental Caries

Streptococcus mutans strains were found to have a substantial role in the development of caries. The objective of this study is to evaluate the potential antibacterial activity of some edible plant extracts against Streptococcus mutans isolates. Fifty oral dental plaque specimens were obtained from various dental clinics in Jeddah city from 23 males and 27 females with median ages ranging between 19.9 to 51.25 years. All isolates were subjected to microbiological, biochemical, and molecular identification. The results showed that 36.3% of the bacterial isolates were identified as Streptococcus mutans, 4.5% as Streptococcus gallolyticus, and 4.5% as Staphylococcus aureus followed by two Yeast species Candida albicans (45.4%) and Candida glabrata (9.0%). The PCR products of the size of 600 and 517 bp DNA fragments were successfully amplified from 16S rRNA and glucosyltransferase gene (gtfb) from the S. mutans isolates and reference strain ATCC25175. The gtfb sequences were submitted to NCBI and assigned accessions MW491783, MW491784, MW491785, and MW491786. Six plant extracts (Guava leaves, Olive Leaves, Clove, Garlic, Green Ginger, and Cinnamon), Nanosilver 12 nm, and commercial kinds of toothpaste: 15% Sensodyne multi-care and 15% Aloe fresh – menta crystal were evaluated against the S. mutans isolates by agar well diffusion test. Most plant extracts tested exhibited considerable inhibitory effects when coupled with Nanosilver 12 nm (1:1). Clove/SNP; 106.8±4.95, and Garlic/SNP; 105.3±3.2) had the greatest mean values of MIC, whereas (Olive/SNP) exhibited the lowest (56.5±3.89). In conclusion, although there are lot of studies on edible plant extracts, incorporating nanoparticles can synergistically increase its antibacterial effectiveness.

Association of sepM gene mutation with mutacin IV production by Streptococcus mutans

To investigate the types of sepM gene mutations and their distribution in clinical isolates of Streptococcus mutans (S. mutans) and explore the association of sepM gene mutation with the capacity of mutacin Ⅳ production by S. mutans. We assessed the capacity of mutacin Ⅳ production in 80 clinical isolates of S. mutans using an inhibition zone assay. The minimum spanning tree and phylogenetic tree of these isolates were constructed using core genome multilocus sequence typing and maximum likelihood method, respectively. GeneMarkS software was used to predict the coding genes of these isolates, and the predicted genes were blasted against the sepM gene sequence of the reference genome UA159 to determine sepM gene mutations and their distribution characteristics in the clinical isolates. The mutation types affecting mutacin Ⅳ production were identified by analyzing the differentially distributed mutations between mutacin Ⅳ-producing isolates and mutacin Ⅳ-free isolates and by comparing the inhibition zones between isolates with sepM gene mutations and those without mutations. Among the 80 clinical isolates of S. mutans, 25 isolates were capable of mutacin Ⅳ production and 55 did not produce mutacin Ⅳ. The minimum spanning tree showed that the allelic differences were less among the mutacin Ⅳproducing isolates than among the mutacin Ⅳ-free isolates, and the origins of the mutacin Ⅳ-producing isolates were similar. We identified a total of 34 single base mutations in the 80 clinical isolates, and among them, C31T (P=0.001), G533A (P < 0.001), C756T (P=0.025), and C1036T (P=0.003) showed significant differential distributions between the mutacin Ⅳ-producing and mutacin Ⅳ-free isolates. These differentially distributed mutations were positively correlated with the capacity of mutacin Ⅳ production of the bacteria. sepM gene mutations that affect the capacity of mutacin Ⅳ production are present in the clinical strains of S. mutans.

In vitro study of the effect of zinc oxide nanoparticles on Streptococcus mutans isolated from human dental caries

Dental caries is a public health concern worldwide for which Streptococcus mutans has been reported Known as the potential etiology of infection. In recent years, nanotechnology has applied to Creation of novel material properties. The research was studying the effects of Nanoparticles of Zinc Oxide on Streptococcus mutans isolate from dental caries. In this research, Different ZnO NPs concentrations were studied as its anti-bacterial effects on Streptococcus mutans was isolated from dental caries cases. 27 Streptococcus mutans isolates were obtained, which is equivalent to 20% of the total number of 135 isolates. This nanomaterial was chosen because it has a high affinity for human cells and does not cause harm compared to other nanoparticles. The nanoparticles are those very fine materials that can be produced so that their dimensions or the dimensions of their grains range from (1-100) nanometers, and because of the small size of the nanomaterials, which made them behave differently from large-sized materials whose size exceeds 100 nanometers, and because of the small size of the particles. Nanoparticles, which gave them electrical and magnetic properties that differ from large particles of the same compounds. The well diffusion method and the MIC experiment were conducted, and the results were good, as in the well diffusion method the efficacy increased with increasing the concentration of ZnO NPs. In the MIC experiment, it was observed that MIC in the sixth tube, meaning that the MIC of ZnO NPs towards Streptococcus mutans equals 0. 312 mg / ml.

Phenotypic and genetic characteristics of Streptococcus mutans isolates from site-specific dental plaque in China.

Introduction. Streptococcus mutans is an important cariogenic microbe.Hypothesis/Gap Statement. The potential characteristics of S. mutans isolates from site-specific dental plaque are still not clear.Aim. This study aimed to investigate the phenotypic and genetic characteristics of S. mutans isolates from site-specific dental plaque in China.Methodology. We used S. mutans isolated from children with early-childhood caries (ECC) and caries-free children to compare the phenotypic and genetic characteristics of S. mutans from site-specific dental plaque samples. The ECC subjects presented two sites: a cavitated lesion and a sound surface. The caries-free subjects presented one sound surface. Growth pattern, biofilm, decrease in pH, extracellular polysaccharide, expression levels of virulence-related genes, multilocus sequence typing (MLST) and phylogenetic trees were evaluated among these three sites.Results. The phenotypes detected between the cavitated and sound surfaces of ECC children were similar. However, the capacity for biofilm formation, pH drop and expression levels of genes (gtfB and spaP) of S. mutans in the caries-free group were lower compared with those of the ECC group. We identified 44 new alleles and 77 new sequence types. More than 90 % of the children with ECC shared an identical sequence type. The distribution of sequence types among different subjects showed diversity, and child-to-child transmission was detected.Conclusions. This is the first report of MLST on site-specific dental plaques in a single subject, and indicates that S. mutans isolated from site-specific dental plaque of a single subject showed similar phenotypes as a result of the isolates were closely related.

Green Synthesis, Characterization of Zinc Oxide Nanoparticles and their Incorporation into Glass Ionomer Cement for Inhibition of Streptococcus mutans

In present study, zinc oxide nanoparticles were synthesised using Syzygium aromaticum and characterized using UV visible spectroscopy, SEM, XRD and FTIR techniques. The characteristic hexagonal structure of the ZnO nanoparticles was confirmed through XRD analysis. The UV-Visible spectrum showed a strong absorbance at 366 nm confirming the presence of ZnO and the peak at 496 cm-1 in FTIR indicated the Zn-O stretch bond. Average size of the zinc oxide nanoparticles obtained from SEM analysis was found to be 86 nm. The zinc oxide nanoparticles exhibited better antibacterial activity than clove extract, when tested against clinical isolates of Streptococcus mutans. The nanoparticles incorporated into the dental restorative material, glass ionomer cement (GIC) were tested against S. mutans and exhibited better antibacterial activity than clove extract. Glass ionomer cement (GIC) did not exhibit antibacterial activity alone, but the incorporation of ZnO nanoparticles into GIC significantly improved antibacterial activity. Hence, ZnO embedded GIC is a promising material in restorative dentistry for preventing the recurrence of dental caries.

Evaluate the efficacy of Probiotic Lactobacilli on growth and biofilm formation in Streptococcus mutans isolated from gingivitis

The present study aimed to assess the antibacterial effects of Probiotic Lactobacilli against Streptococcus mutans isolates. A total of 13/52 (25%) S. mutans isolates were collected from patients suffering from gingivitis, which were identified using morphological characteristics, biochemical tests and PCR technique. Micro titer plate method was used to detect the biofilm formation in tested bacterial isolates by measuring optical density (OD) using ELISA reader at a wavelength 640 nm. The results revealed that only 10/13 (77%) isolates produced the biofilm. Based on the results obtained in this study, the isolates were classified according to their ability to the biofilm formation as follows: the isolates with thick biofilm (OD ≥ 0.300 nm), the isolates with moderate biofilm (OD 0.2-0.3 nm), the isolates with thin biofilm (OD 0.1-0.2 nm) and Non-productive isolates of biofilm (OD < 0.1 nm). On the other hand, the agar well diffusion method was used to evaluate the effectiveness of Probiotic Lactobacilli against the growth of bacterial isolates by measuring the inhibition zones around the wells containing of probiotics (50, 100 mg/ml and stock). The results indicate that inhibition zones of the tested isolates were weak at 50 mg/ml, moderate at 100 mg/ml and strong at stock solution. A modified crystal violet test in well micro-titer plates was used to detect the ability of isolates to the biofilm formation after treatment with various concentrations of Probiotic Lactobacilli by measuring optical density (OD). The results indicate a decrease in the ability of the tested isolates to the biofilm formation compared to control where the isolates treated with probiotics at 50 mg/ml formed a strong biofilm (OD 0.300 - 0.341 nm) and the isolates treated with probiotics at 100 mg/ml formed moderate biofilm (OD 0.209 - 0.263 nm), while the isolates treated with the stock solution of probiotics formed a thin biofilm (OD 0.144 - 0.198 nm). In conclusion, the results of the current study indicate that the Probiotic Lactobacilli have inhibitory effect on growth and biofilm formation in Streptococcus mutans isolates and the antibacterial activity of Probiotic Lactobacilli is increased with increasing concentration.

The Anti-Biofilm Activity of Oregano Essential Oil Against Dental Plaque-Forming Streptococcus mutans In Vitro and In Vivo

Background: The oral and dental infections that are mainly caused by bacterial biofilms are among the most prevalent human infections worldwide. Objectives: The present study aimed to investigate the in vitro and in vivo inhibitory and anti-biofilm effects of oregano essential oil on the Streptococcus mutans isolates obtained from elementary school students. Methods: This experimental study was conducted on 150 samples collected from the buccal and lingual surfaces of the posterior teeth of elementary school students. S. mutans strains were identified using conventional microbiological and biochemical tests, and biofilm formation was assessed using the microtiter plate assay. The minimum inhibitory concentration (MIC) of the oregano essential oil against the isolates was determined using the broth microdilution method. In addition, the effective constituents of the essential oil were measured via gas chromatography-mass spectroscopy. The in vitro and in vivo anti-biofilm activities of the oregano essential oil were also evaluated using the modified microtiter plate assay and on the tooth surfaces of male NMRI mice, respectively. Results: The frequency of S. mutans was 15.3%, 87% of which were capable of biofilm formation. The MIC of the oregano essential oil was 50 µl/ml against the S. mutans isolates, and 82% of the isolates did not grow at the concentrations of ≥ 512 µl/ml. However, none of the isolates were capable of biofilm formation at the MIC and sub-MIC concentrations of the essential oil. Limonene and myrcene were the most effective constituents of the essential oil. Furthermore, a significant correlation was observed between treatment with the oregano essential oil and biofilm formation by the streptococci isolates (P = 0.05). Conclusions: According to the results, the presence of biofilm and incidence of dental caries were significantly correlated. Moreover, the essential oil of oregano and its main constituents had potent anti-biofilm and antibacterial properties and could be utilized for the production of new plant-based mouthwashes.

Linden tea from Serbia – an insight into the phenolic profile, radical scavenging and antimicrobial activities

Linden tea has been used in Serbian folk medicine for centuries to induce sweating for colds, relieve throat irritation and cough, reduce blood pressure, as well as a diuretic, spasmolytic, and as a sedative. The main aim of this study was to determine the comprehensive metabolite profile, free radical scavenging activity, and antimicrobial activities against 23 human and plant pathogens of both commercial and field-collected linden tea samples from Serbia. Developed high-performance thin-layer chromatography (HPTLC) method allowed identification of eight major metabolites in investigated samples, while forty-six metabolites were tentatively identified using high resolution mass spectrometry (HRMS): 14 phenolic acids and their derivatives, 15 glycosides, 9 flavonoids, and 8 procyanidins. Both commercial and field-collected linden tea samples showed similar total phenolic content and radical scavenging activity. Seven compounds such as p-hydroxybenzoic acid 4-O-hexoside, caffeic acid cinnamyl ester, pinocembrin, galangin, luteolin 7-O-glucuronide (and its isomer), isorhamnetin hexosyl hexoside were found in Tilia samples for the first time. Radical reagent 2,2-Diphenyl-1-picrylhydrazyl· (DPPH·) was used in DPPH-HPTLC assay which identified chlorogenic acid, caffeic acid, astragalin, quercitrin, tiliroside, and rutin as compounds that exhibit radical scavenging activity. Tilia samples showed inhibitory effect overwhelming only on Gram-positive bacteria, especially on Bacillus subtilis with the lowest MIC values observed, as well as towards Staphylococcus aureus and oral cavity isolates of Streptococcus pyogenes and Streptococcus mutans. Vaginal isolate of Candida glabrata showed more susceptibility than Candida albicans isolate. Generally, extract from Tilia cordata Miller (L4) showed the highest antimicrobial activity against the most of the tested pathogens, among all field-collected Tilia samples.

Phytochemical, Cytotoxic, and Antimicrobial Evaluation of the Fruits of Miswak Plant, Salvadora persica L.

Salvadora persica L. (Salvadoraceae) is an evergreen shrub growing in the Middle East, Africa, and Southern Asia. It is traditionally known as “miswak” and used as toothbrushes and for the treatment of toothache, gum diseases, boils, chest infection, gonorrhea, headache, spleen troubles, stomachache, and ulcers. To the best of our knowledge, this is the first study aimed at conducting phytochemical, cytotoxic, and antimicrobial investigations of the fruits (berries) of S. persica collected from the Jazan region of Saudi Arabia. Analysis of the ethanol extract of S. persica fruits using GC-MS showed the presence of six esters (20.71%), seven alkanes (15.47%), tetracosamethyl-cyclododecasiloxane (9.91%), eicosamethyl-cyclodecasiloxane (7.27%), and 1-monolinoleoylglycerol (5.17%). The predominant constituents were acetyl dasycarpidan-1-methanol (10.47%), tetracosamethyl-cyclododecasiloxane (9.91%), eicosamethyl-cyclodecasiloxane (7.27%), and 1-monolinoleoylglycerol (5.17%). The petroleum ether extract of the fruits contained mainly eicosamethyl-cyclodecasiloxane (23.81%), 1-monolinoleoylglycerol (11.78%), (Z,Z,Z)-9,12,15-octadecatrienoic acid ethyl ester derivative (10.56%), and tetracosamethyl-cyclododecasiloxane (9.91%). The cytotoxic properties of the ethanol extract were investigated by MTT assay against the breast MCF7, ovary A2780, and colon HT29 cells. The fruit extract of S. persica was selective against the ovarian and colon cancer cells compared to normal fibroblast cells (MRC5) as it showed IC50 values 17.50, 8.35, and 5.12, against MCF7, A2780, and HT29 cells, respectively. Interestingly, the fruit extract was also found to possess selective antimicrobial activity for Streptococcus mutans isolates with minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) values of 3.12 and 6.25 mg/mL, respectively. Interestingly, it was found to be ineffective against other Gram-positive as well as Gram-negative microorganisms. This study provides insight into the bioactive components present in the fruits of the plant that can be utilized for its cytotoxic and antimicrobial properties.

Comparative Evaluation of the Antimicrobial Effects of Different Mouthrinses against Oral Pathogens: An In Vitro Study1

To assess the antimicrobial effects of natural and semi-natural mouthrinses on isolates of Streptococcus mutans, Lactobacillus fermentum, and Lactobacillus casei obtained from the saliva samples and their reference strains. Natural and semi-natural mouthrinses included in this study were herbal mix mouthrinse, cranberry mouthrinse, chlorhexidine digluconate mouthrinse, cranberry extract mixed with chlorhexidine digluconate mouthrinse, chlorhexidine digluconate mouthrinse with alcohol (positive control), and distilled water (negative control). The microbiological examination tests were minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC), and zone of inhibition test for the saliva isolates of S. mutans, L. fermentum, and L. casei while zone of inhibition test only for their reference strains. Compared with distilled water, herbal mix, cranberry, cranberry mixed with chlorhexidine, chlorhexidine with alcohol (+), and chlorhexidine mouthrinses were associated with a significant increase of the zone of inhibition 34.354, 34.255, 34.219, 10.801, and 9.386, respectively. Both MIC and MBC were significantly higher in the cranberry mixed with chlorhexidine than in chlorhexidine with alcohol. The MIC and MBC of mouthrinses were significantly lower in the S. mutans and L. fermentum than in L. casei. Herbal mix and cranberry mouthrinses could be effective natural alternative to chlorhexidine mouthrinse with or without alcohol in improving oral health. Different mouthrinses proposed in this study showed antimicrobial effects against the tested oral pathogens, and possibly the tested mouthrinses will lead for future formulation of natural or semi-natural pharmaceutical mouthrinses.