Antimicrobial activity of a novel Spanish propolis against planktonic and sessile oral Streptococcus spp

Increased bacterial resistance to traditional antimicrobial agents has prompted the use of natural products with antimicrobial properties such as propolis, extensively employed since ancient times. However, the chemical composition of propolis extracts is extremely complex and has been shown to vary depending on the region and season of collection, due to variations in the flora from which the pharmacological substances are obtained, being therefore essential for their antimicrobial activity to be checked before use. For this purpose, we evaluate the in vitro antimicrobial and anti-biofilm activity of a new and promising Spanish ethanolic extract of propolis (SEEP) on Streptococcus mutans and Streptococcus sanguinis, responsible, as dominant ‘pioneer’ species, for dental plaque. Results reveal that S. sanguinis is more sensitive to SEEP, slowing and retarding its growth considerably with lower concentrations than those needed to produce the same effect in S. mutans. SEEP presents concentration- and time-dependent killing activity and, furthermore, some of the subinhibitory concentrations employed increased biofilm formation even when bacterial growth decreased. Mono and dual-species biofilms were also inhibited by SEEP. Findings obtained clearly show the relevance of using biofilm and subinhibitory concentration models to determine optimal treatment concentrations.

A Parallel Tracking of Salivary and Gut Microbiota Profiles Can Reveal Maturation and Interplay of Early Life Microbial Communities in Healthy Infants

The onset and progression of the salivary and gut microbiota, the transmission and the impact of the salivary microbiota on the development of early fecal microbial communities was herein explored. We characterized the microbiota of 82 faecal and 80 salivary samples, collected from 82 healty newborns at birth, 7, 15, 30, 90 and 180 days of life, by 16S rRNA targeted-metagenomics approach. Correlation heat-maps and co-occurrence networks were used to investigate microbial taxa relationship in saliva, gut and between the two ecosystems. In saliva microbiota, Streptococcus and Staphylococcus appeared as early commensals, dominating this ecosystem through the time, while Fusobacterium, Prevotella, Porphyromonas, Granulicatella and Veillonella were late colonizers. anaerobes as Enterobacteriace, Staphylococcus and Streptococcus, were gut microbiota pioneers, followed by the anaerobic Bifidobacterium, Veillonella, Eggerthella and Bacteroides. Streptococcus, Staphylococcus and Veillonella were shared by gut and saliva ecosystems (core microbiota). Early saliva and gut microbiota seem to evolve independently driven by local adaptation strategies, with the only exception for the oral Streptococcus and Veillonella genera, involved in gut microbiota development as seeding species. A more comprehensive knowledge of how oral microbiota may impact pathophysiological conditions of gut microbiota may open new avenues on the design of postbiotics.

The antibacterial effect of β-pinene derived from Citrus aurantifolia against oral Streptococcus mutans

Introduction: Streptococcus mutans has been known to play a major role in dental caries development. This tooth decay is the most common oral disease affecting people in the world. Hence, discovering the new herbal antibacterial agent seems to become promising yet challenging. One of herbal antibacterial source is Jeruk Nipis or namely Citrus aurantifolia, as it is believed to contain biological active compounds that may act as antibacterial to kill pathogenic oral microbes. This study was aimed evaluated antibacterial effect of β-pinene derived from Citrus aurantifolia against oral Streptococcus mutans. Methods: Type of research is quasi experimental research. The essential of C. aurantifolia essential oil was prepared and isolated using the hydro-distillation technique and further isolation of antibacterial compounds was conducted by combination column chromatography using organic solvent, and the structure was determined by infrared (IR), 1D NMR of 1H-, 13C-NMR and DEPT 135° in CDCl3, and UV-Vis spectrometer methods. The antibacterial activity was tested against Streptococcus mutans using the Kirby-Bauer method. Results: 0.75% yield was extracted from the essential oil of Citrus aurantifolia and after purification, an antibacterial compound was identified as β-pinene with the molecular formula C10H16. Furthermore, the Citrus aurantifolia exerted inhibition growth of Streptococcus mutans at concentration of 2000, 1000, and 500 ppm showed reduction in paper disk as much as 13.0, 11.9, and 11.6 mm respectively. Conclusion: Antibacterial effect of β-pinene derived from Citrus aurantifolia against oral Streptococcus mutans. This is proven that β-pinene derived from Citrus aurantifolia prospective as antibacterial compound that potentially can be used as another herbal antibacterial of choice to manage dental disease associated with Streptococcus mutans infection.

Antimicrobial Photodynamic Treatment with Mother Juices and their Single Compounds as Photosensitizers

The potent antimicrobial effects of antimicrobial photodynamic therapy (aPDT) with visible light plus water-filtered infrared-A irradiation and natural compounds as photosensitizers (PSs) have recently been demonstrated. The aim of this study was to obtain information on the antimicrobial effects of aPDT with mother juices against typical cariogenic oral Streptococcus pathogens in their planktonic form and determine its eradication potential on total human salivary bacteria from volunteers. Mother juices of pomegranate, bilberry, and chokeberry at different concentrations were used as PSs. The unweighted (absolute) irradiance was 200 mW cm−2, applied five minutes. Planktonic cultures of Streptococcus mutans and Streptococcus sobrinus and total mixed bacteria from pooled saliva of volunteers were treated with aPDT. Up to more than 5 log10 of S. mutans and S. sobrinus were killed by aPDT with 0.4% and 0.8% pomegranate juice, 3% and 50% chokeberry juice, and 12.5% bilberry juice (both strains). Concentrations of at least 25% (pomegranate) and >50% (chokeberry and bilberry) eradicated the mixed bacteria in saliva samples. This pilot study has shown that pomegranate mother juice is superior to the berry juices as a multicomponent PS for killing pathogenic oral bacteria with aPDT.

Efficacy of Feed-Based Formalin-Killed Vaccine of Streptococcus iniae Stimulates the Gut-Associated Lymphoid Tissues and Immune Response of Red Hybrid Tilapia

Red hybrid tilapia were fed a formalin-killed oral Streptococcus iniae vaccine (FKV) in the present study was assessed. Three hundred Red hybrid tilapia 80 ± 10 g were divided into five groups (1A, 1B, 2A, 2B, and Cx), each consisting of 60 fish. Fish from Groups 1A, 1B, 2A, and 2B were fed with FKV over different periods of administration, while Group 2B was the only group of fish to receive an oral booster vaccination on day 14- and 21-days post-vaccination (dpv). Group Cx was fed with normal pellets containing no vaccine as a control group. At four weeks post-vaccination (wpv), all fish were experimentally infected with S. iniae. Groups 2A and 2B had the lowest level of mortalities following vaccination (45% and 30%, respectively) compared to Groups 1A and 1B (80% and 55%, respectively), while the level of mortalities in Group Cx was 100%. All vaccinated groups showed a significant increase in anti-S. iniae IgM levels (p < 0.05) in serum, mucus, and gut-lavage, while Group Cx did not (p > 0.05) and all fish in this group died by five weeks post-infection. In conclusion, fish fed with the S. iniae FKV had a greater level of protection against S. iniae, with increased specific antibody response to the vaccine and there was also evidence of GALT stimulation by the vaccine.