Antimicrobial effects of surface pre-reacted glass-ionomer (S-PRG) eluate against oral microcosm biofilm.

This study investigated the antimicrobial activity of surface pre-reacted glass ionomer eluate (S-PRG) against oral microcosm biofilms collected from the oral cavity of patients. Dental biofilm samples were collected from three volunteers to form microcosm biofilms in vitro. Initially, screening tests were carried out to determine the biofilm treatment conditions with S-PRG eluate. The effects of a daily treatment for 5 min using three microcosm biofilms from different patients was then evaluated. For this, biofilms were formed on tooth enamel specimens for 120 h. Biofilms treated with 100% S-PRG for 5 min per day for 5 days showed a reduction in the number of total microorganisms, streptococci and mutans streptococci. SEM images confirmed a reduction in the biofilm after treatment. Furthermore, S-PRG also reduced lactic acid production. It was concluded that S-PRG eluate reduced the microbial load and lactic acid production in oral microcosm biofilms, reinforcing its promising use as a mouthwash agent.

Farnesol as a potentiator of antimicrobial photodynamic inactivation on Enterococcus faecalis.

Enterococcus faecalis is related to the recurrence of endodontic infections and approaches to intracanal disinfection are necessary. Farnesol, an alcohol commonly found in propolis, has antimicrobial properties, and can enhance the efficacy of some antibiotic therapies. The objective was to evaluate whether farnesol can increase the efficacy of the antimicrobial photodynamic inactivation (aPDI) on E. faecalis, investigating its action on planktonic growth, biofilms, and cell permeability. Planktonic cells and biofilms of E. faecalis were pre-treated with farnesol (0.25 mM) 2 h before aPDI. Methylene blue (1 mg/mL) and laser (660 nm) were employed in the aPDI. As a result, farnesol was able to increase the antimicrobial activity of aPDI in both planktonic and biofilm stages, reaching cell reductions of 4.6 to 6 log10 CFU and 1.3 to 3 log10 CFU, respectively, when compared to aPDI isolated. The efficacy of farnesol in enhancing the anti-biofilm activity of aPDI was also confirmed by electron microscopy, in which a smaller number of bacterial cells and extracellular matrix were verified in the combined therapy compared to aPDI alone. The potentiating action of farnesol was associated with its effects in increasing the cell permeability and methylene blue uptake by the bacterial cells. Therefore, farnesol can be a promising potentiator of aPDI against E. faecalis.

Lactobacillus species increase the survival of Galleria mellonella infected with Candida albicans and non-albicans Candida clinical isolates.

Investigation into new therapeutic strategies, such as the use of bacterial isolates with probiotic characteristics, has increased in importance due to the high incidence of Candida albicans and non-albicans Candida infections. This study evaluates Lactobacillus paracasei, Lactobacillus fermentum and Lactobacillus rhamnosus strains as prophylactic and therapeutic agents against infection caused by Candida albicans, Candida glabrata, Candida krusei, and Candida tropicalis in a Galleria mellonella model. Prophylactic treatment provided greater benefits during Candida spp. infection, increasing G. mellonella survival, compared to therapeutic treatment. This study demonstrated that the different Lactobacillus species are potent prophylactic agents of Candida species infection.