Methods: The experiment was carried out in Azra Naheed Center for Research and Development (ANCRD), Superior University, Lahore, Pakistan from September 2018 till May 2019. Biofilms and planktonic cells of C. albicans alone and in combination with streptococci were subjected to chlorhexidine, allium sativum and bakuchiol individually and to allium-bakuchiol combination. Kirby-Bauer test, antifungal susceptibility testing, CFU count and drug synergy assessment was done on planktonic cells. Dynamic biofilms were formed to mimic conditions similar to oral cavity and CFU was determined.
Results: MIC of all three agents was higher against mixed species when compared to single species planktonic cells and biofilm. Allium sativum and bakuchiol demonstrated synergistic effects. The decrease in CFU count and minimum biofilm reduction to salivary pellicle caused by allium sativum-bakuchiol was comparable to that of chlorhexidine.
Conclusion: Thus, allium sativum-bakuchiol combination demonstrated antimicrobial effects similar to chlorhexidine against planktonic cells and dynamic biofilm. It could serve as a possible natural, economical alternative to chlorhexidine mouthrinses usually recommended in dental clinics. However, in vivo studies are required to determine the correct dosage of these agents.
Methods: In the current study, a transcriptome investigation was performed to explore the mechanism underlying the biofilm dispersal of P. aeruginosa after the exposure to Trigona honey.
Results: Microarray analysis of the Pseudomonas biofilm treated by 20% Trigona honey has revealed a down-regulation of 3478 genes among the 6085 screened genes. Specifically, around 13.5% of the down-regulated genes were biofilm-associated genes. The mapping of the biofilm-associated pathways has shown an ultimate decrease in the expression levels of the D-GMP signaling pathway and diguanylate cyclases (DGCs) genes responsible for c-di-GMP formation.
Conclusion: We predominantly report the lowering of c-di-GMP through the down-regulation of DGC genes as the main mechanism of biofilm inhibition by Trigona honey.
RESULTS: The floatation of spike balls created a turbulent flow, thereby inhibiting further biofilm formation. The parameters such as, specific growth rate and doubling time of the algae before introducing the balls were 0.451 day-1 and 1.5 days respectively. Visible biofilm impeding light transmission was formed by 15-20 days. The removal of the biofilm commenced immediately after the introduction of the spike balls with visibly reduced deposits in 3 days. This was also validated by enhance cell count (6.95 × 106 cells mL-1) in the medium. The employment of spike balls in PBR is an environmental friendly and economical method for the removal of biofilm.
PURPOSE: The purpose of this in vitro study was to assess the antimicrobial effect of sub 10-nm AgNPs in maxillofacial silicone against Staphylococcus aureus, Candida albicans, and mixed species biofilms containing both and to test the effectiveness of different AgNP concentrations against all 3 biofilms in vitro.
MATERIAL AND METHODS: Silicone disks (M511; Technovent Ltd) containing 0.0% (control), 0.1%, and 0.5% AgNPs were fabricated and treated with S. aureus, C. albicans, and mixed species strains of both in 24-well culture plates containing appropriate media. Each well received a 0.1-mL aliquot of the standardized suspension of microorganisms. The plates were incubated for 21 consecutive days, and colony-forming units per milliliter (CFU/mL) were measured on the first, third, fifth, seventh, fifteenth, and twenty-first day with the Miles and Misra method. Data were analyzed by 2-way ANOVA and the paired t test to evaluate the relationship between AgNP concentration, microbial strain, and time (α=.05). Mean CFU/mL differences for each time and for each biofilm category were assessed by repeated measure ANOVA.
RESULTS: AgNPs decreased the mean CFU/mL in both concentrations compared with the control. The 0.1% concentration showed sustained efficacy throughout the test, while the 0.5% concentration had high efficacy initially with a gradual decrease. However, the results were inconsistent for the mixed biofilm. The paired sample t test at day 3 and 15 and day 3 and 21 showed statistically significantly different results (P