Antibacterial Effect of Hypochlorous Acid on Bacteria Associated with the Formation of Periodontal Biofilms: An in vitro Pilot Study

ABSTRACT Objective: To evaluate the antibacterial effect of electrolytically generated hypochlorous acid on Streptococcus gordonii, Fusobacterium nucleatum, and Porphyromonas gingivalis. Material and Methods: In this in vitro experiment, the effect of hypochlorous acid (HOCl) on the strains S. gordonii, F. nucleatum, and P. gingivalis was evaluated using 4% sodium hypochlorite, 0.12% chlorhexidine, and distilled water as controls. The four groups were placed on each plate, and each group was replicated five times. The agar diffusion method by zones measurement was used. The data were processed with SPSS using the Kruskal-Wallis test and multiple comparison tests. Results: Hypochlorous acid showed an average inhibition halo of 9.28 mm on S. gordonii. As expected with distilled water, no zone of inhibition was noted for any of the bacteria, nor were zones of inhibition observed with HOCl for F. nucleatum and P. gingivalis. Conclusion: Hypochlorous acid showed antimicrobial properties against only S. gordonii and was less effective than 4% sodium hypochlorite and 0.12% chlorhexidine, although no significant differences were found between the latter.

Research policies and scientific production: A study of 94 Peruvian universities.

Studies of research policies and scientific production are essential for strengthening educational systems and achieving objectives such as quality improvement. The aim of this study was to evaluate the influence of research policies on the scientific production of public and private Peruvian universities. An observational, descriptive, secondary analysis study of the research policies of 92 universities and two graduate schools licensed by the National Superintendence of Higher Education of Peru (SUNEDU) was conducted for the period from 2016-2020. Scientific publications from educational institutions were collected from Scopus and Web of Science for the study period, and researchers certified by the National Council of Science and Technology of Peru (CONCYTEC) were divided by group and level. Multiple regression analysis was performed using two models. The analysis indicated that research policies did not influence scientific production in Scopus or Web of Science in either 2019 or 2020 (Model I) but that type of management (p < 0.01), number of National Scientific, Technological, and Technological Innovation Registry (RENACYT) researchers (p < 0.001) and 2016 scientific production (p < 0.001) did influence production when these variables were incorporated into the model (Model II). However, time of licensing and management type had no effects. The number of research policies implemented by Peruvian universities and licensed graduate schools was not large. Therefore, it is recommended that project funding policies, research training, and research collaboration be strengthened and that the management capacity of research centers and institutes be increased.

Identification of Proteins Associated with the Formation of Oral Biofilms

ABSTRACT Objective: To identify proteins associated with the formation of Streptococcus gordonii and Fusobacterium nucleatum biofilms. Material and Methods: Biofilms composed of two bacterial species, S. gordonii and F. nucleatum, were cultured for 1, 4, 7, and 10 days. The presence of both species was confirmed via amplification of the srtA and radD genes using real-time PCR. The concentrations of proteins associated with the biofilms and individual species were quantified using Western blotting. Results: The protein profiles of S. gordonii and F. nucleatum from individual cultures determined using one-dimensional electrophoresis revealed proteins found in S. gordonii and in F. nucleatum. Ct and reciprocal Ct values were determined for the exposed S. gordonii and F. nucleatum biofilms. Glyceraldehyde 3-phosphate dehydrogenase (GAPDH) protein was detected in biofilms and F. nucleatum, whereas HSP40 protein was present only in biofilms after 7 and 10 days of formation. Conclusion: HSP40 was detected only in the formed biofilms; thus, HSP40 is an essential proteins for adhesion.

Antimicrobial Activity and Antiadherent Effect of Peruvian Psidium guajava (Guava) Leaves on a Cariogenic Biofilm Model.

AIM: Phytomedicine has been commonly practiced as a form of traditional medicine in various cultures for the treatment of oral diseases. Recently, it has gained importance as an alternative to conventional treatment. Several extracts of plants and fruits have been recently evaluated for their potential activity against microorganisms involved in the development of dental caries. The purpose of this study was to evaluate the antimicrobial activity and antiadherent effect of the crude organic extract (COE) and three partitions (aqueous, butanolic, and chloroformic) of Psidium guajava (guava) leaves on a cariogenic biofilm model. MATERIALS AND METHODS: Guava leaves were obtained from the mountains of northern Peru, where they grow wild and free of pesticides. The antimicrobial activity of the COEs and partitions against Streptococcus mutans and Streptococcus gordonii was determined by measuring the inhibition halos, while the effect on biofilm adhesion was determined by measuring the optical density using spectrophotometry. RESULTS: An antibacterial effect of the COE and chloroformic partition against S. gordonii (p < 0.05) was found, as was a significant effect on biofilm adherence, with a minimum inhibitory concentration (MIC) of 0.78 mg/mL, which was maintained throughout the 7 days of evaluation. CONCLUSION: We conclude that the COEs and their chloroformic partition have antimicrobial and antibiotic effects against this strain of S. gordonii, making them of particular interest for evaluation as a promising alternative for the prevention of dental caries. CLINICAL SIGNIFICANCE: By knowing the antimicrobial effect of Psidium guajava, this substance can be effectively used in products aimed to prevent dental caries and periodontal disease.

Antifungal Activity of Peruvian Banana Peel (Musa paradisiaca L.) on Candida albicans: An In Vitro Study.

AIM: The purpose of this study was to compare the antifungal activity of three concentrations of a hydroethanolic extract of the Musa × paradisiaca peel against Candida albicans strain ATCC 10231. MATERIALS AND METHODS: The agar diffusion method was used, and the culture medium used was Sabouraud agar. Petri dishes were prepared with concentrations of 10, 30, and 50% of hydroethanolic extract of the M. × paradisiaca peel; nystatin was used as a positive control, and 96% ethanol was used as a negative control. After 24 hours of incubation, each plate was examined, and the diameters (mm) of the growth inhibition halos were measured around each well using a digital vernier caliper. RESULTS: The results showed that the antifungal activity of the extract varied, depending on the concentration, as shown using analysis of variance (ANOVA; p < 0.05). When comparing the different concentrations, it was found by Duncan test that the greatest activity was obtained at 50%. CONCLUSION: It was concluded that the hydroethanolic extract of M. × paradisiaca at 50% exerted a greater antifungal effect on the strain of C. albicans than did the extract at lower concentrations. CLINICAL SIGNIFICANCE: By knowing the antimicrobial effect of M. × paradisiaca, this substance can be effectively used in products aimed to cure candidiasis infection.

Chemical Composition and Antibacterial Effect of Plantago Major Extract on Periodontal Pathogens

Abstract Objective: To determine the in vitro antibacterial effect of different concentrations of the ethanol extract of Plantago major (plantain) on Porphyromonas gingivalis and Fusobacterium nucleatum. Material and Methods: Bacterial susceptibility tests were used in conjunction with the agar diffusion test and the minimum inhibitory concentration (MIC) test using the broth macrodilution technique. Results: Different concentrations of ethanol extract (25%, 50%, 75% and 100%) dissolved in 70% ethanol were used, with a positive control (0.12% chlorhexidine + 0.05% cetyl-pyridinium chloride) and a negative control (70% alcohol). The extracts at 75% and 100% showed inhibition halos against both strains studied. With 0.12% chlorhexidine + 0.05% cetyl-pyridinium chloride, inhibition halos averaged 14.9 mm, in contrast to 70º alcohol, where no bacterial inhibition was observed. The MIC was 50% for both species. Conclusion: The ethanol extract of Plantago major presents an in vitro antibacterial effect on Porphyromonas gingivalis, they may have potential applications in food and pharmaceutical products.