IntroductionThe Aloysia citriodora plant from the family of Verbenaceae has many uses in traditional medicine. The aim of the current study was to determine the effects of the aqueous and ethanolic extracts of A. citriodora on Streptococcus mutans and Streptococcus sobrinus, which cause tooth decay.MethodsThis 2016 study was performed on standardized strains of S. mutans PTCC1683 and S. sobrinus PTCC1601 and clinical isolates. Twenty clinical samples were obtained from the dental caries of children admitted to the pediatric ward at the Faculty of Dentistry of Babol University of Medical Sciences (Babol, Iran). The aqueous and ethanolic extracts of A. citriodora leaves were prepared in several concentrations ranging from 625–20,000 μg/ml. These concentrations of the extracts were applied to the bacteria by disk diffusion, agar well diffusion, and macrotube dilution. The antibacterial effects of amoxicillin and chlorhexidine digluconate 0.2% (CHX) were also carried out. Data were analyzed by SPSS version 18 software using independent-samples t-test.ResultsStreptococcus spp. was successfully isolated from nine out of 20 (45%) specimens. Of the 9 positive samples cultured, 8 (88.8%) were S. mutans and 1 was S. sobrinus (11.2%). No inhibitory zone was observed around the disks and wells containing all concentrations of A. citriodora extracts. The minimum concentrations for inhibition of growth (MIC) resulted in turbidity in all tubes and were negative except for the control tubes. Inhibition zones were observed for amoxicillin and CHX disks (p < 0.001).ConclusionThis study found that all studied bacteria were resistant to both types of the extracts; therefore, they are not a suggested replacement for chemical agents in mouthwash. It also shown that CHX is less effective than amoxicillin.

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IntroductionBecause of resistance and side effects to common antifungal drugs activity, the research on herbal substances with antifungal activity is frequent. Lemon verbena (Lippia citriodora) is a member of Verbenaceae family. The aim of this study was to determine the anti-candida activities of the ethanolic and aqueous extracts of the lemon verbena leaves and compare them with nystatin and fluconazole.MethodsIn this 2015 study, 15 clinical isolates and standard strain of candida albicans PTCC 5027 were used, and the inhibitory effects of the ethanolic and aqueous extracts, Nystatin and Fluconazole, were evaluated using disk and well diffusion methods. Also, the minimal inhibitory concentration (MIC) was determined. Five concentrations of aqueous and ethanolic extracts (156–2500 μg/ml), Nystatin (8–128 μg/ml) and Fluconazole (4–64 μg/ml) were used in disk and well diffusion methods, and nine concentrations of aqueous and ethanolic extracts (19–5000 μg/ml), Nystatin (0.5–128 μg/ml), and Fluconazole (0.25–64 μg/ml) were applied for MIC. Data were analyzed using Tukey’s post-hoc and one-way ANOVA tests. The significant level was considered p < 0.05 in the current study.ResultsIn the well and disk diffusion techniques, limited growth inhibition halos were produced around some clinical isolates at different concentrations of ethanolic extract; however, no growth inhibitory halo was observed with any concentrations of the aqueous extract. The MIC values of ethanolic extract, aqueous extract, Nystatin and Fluconazole for clinical isolated and standard strain were 833 ± 78.5and 625μg/ml; 4156 ± 67.4 and 2500 μg/ml; 10.13 ± 1.91 and 4 μg/ml; and 1.97 ± 0.25 and 1 μg/ml, respectively.ConclusionThe results showed that the ethanolic extract was stronger than the aqueous extract of this plant, which can be used as an alternative for drugs. It is recommended that the ethanolic extract of this plant be investigated in vivo for better evaluation of its efficacy and properties.

10.30699/jambs.28.130.291 Background & Objective: Candida species, and most frequently isolated Candida albicans, are normal microorganisms of oral cavities; however, C. albicans is responsible for oral cavities in children with dental caries. As a new biologic technique, using probiotics has gained popularity in preventing and controlling diseases at present. Enterococcus durans has exhibited useful antioxidative properties and antibacterial and probiotic characteristics. This study aims to evaluate the effects of probiotic Enterococcus durans on the in vitro adhesion of Candida albicans. Materials & Methods: Reference bacteria strain of probiotic E. durans (ATCC 6056), C. albicans reference strain (PTCC-5027), and 10 clinical samples of C. albicans were provided. Adherence inhibition of Candida albicans was measured using microtiter plates applying two methods (addition of a mixed suspension of C. albicans and E. durans simultaneously and addition of E. durans 30 minutes before C. albicans). Data were analyzed with a repeated measure model. Statistical significance was set at P-value<0.01. Results: Adhesions of C. albicans biofilms decreased in the presence of the probiotic strain E. durans. Mean OD620 nm was within the range of 0.45 to 0.49, and 0.33 for OD490 nm. Conclusion: Using E. durans as a probiotic could reduce Candida albicans adhesion and, therefore, can be considered as an effective way to decrease its pathogenicity.

Background: Streptococcus mutans is the most cariogenic microorganism with high adherence ability to the tooth surfaces. The probiotics have attracted attention as a new and bioecological technique to inhibit oral bacterial colonization. Enterococcal strains, such as Enterococcus durans, are abundant in nature and can be identified as a probiotic. Objectives: Since the reduction of adhesion can be an effective way to decrease the cariogenic potential of S. mutans, the present study aimed to evaluate the inhibitory effect of E. durans on the adhesion of S. mutans. Methods: In this in vitro study, the standard strain bacteria of probiotic E. durans and Streptococcus mutans and 12 clinical samples of S. mutans were used. The ability of S. mutans biofilm formation was assessed. Then, the effect of E. durans on S. mutans adhesion was determined via microtiter plate technique by two methods: (1) Adding a mixed suspension of E. durans and S. mutans simultaneously; (2) adding E. durans 30 minutes before the inoculation of S. mutans to the system. The data were analyzed with SPSS 20 by using paired t-test, and statistical significance was set at P < 0.05. Results: The results showed a decrease in adhesion in the presence of E. durans, with the use of both methods (P < 0.05). Conclusions: Based on the results of this in vitro study, the use of probiotic E. durans decreased the adhesion of S. mutans.