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Journal of Oleo Science Oct 2018A microwave-assisted hydrodistillation (MAHD) method was investigated for extraction of essential oils from lavender. The essential oil extracts at optimized MAHD...
A microwave-assisted hydrodistillation (MAHD) method was investigated for extraction of essential oils from lavender. The essential oil extracts at optimized MAHD conditions was compared with hydrodistillation (HD). Response surface methodology coupled with Box-Behnken design was applied to optimize the parameters for MAHD. The optimized MAHD conditions were 500 W microwave power, 17 mL/g liquid-to-solid ratio and 40 min microwave time. The ANOVA results revealed that microwave time had the greatest impact on the essential oil yield followed by liquid-to-solid ratio and microwave power. Under the MAHD optimized conditions, the essential oil yield was 3.19%, approximating the predicted yield (3.20%). MAHD was superior in terms of saving energy and extraction time (40 min, compared to 120 min in HD). The essential oil analyzed by GC-MS, presented 39 compounds constituting 98.37% and 97.51% of the essential oils obtained through MAHD and HD, respectively. No obvious differences were found in composition between MAHD oil and HD oil. Antimicrobial study showed that the lavender essential oil exhibited broad-spectrum antibacterial activity and the MAHD oil showed a higher antimicrobial activity than the HD oil. This study revealed that MAHD could be a good method for extracting essential oil in lavender and other aromatic plants.
Topics: Actinomyces viscosus; Anti-Bacterial Agents; Antifungal Agents; Aspergillus niger; Distillation; Drug Resistance, Bacterial; Drug Resistance, Fungal; Lavandula; Liquid-Liquid Extraction; Microwaves; Oils, Volatile; Penicillium; Plant Oils; Staphylococcus aureus; Time Factors
PubMed: 30210076
DOI: 10.5650/jos.ess18019 -
Respiratory Medicine Case Reports 2018Actinomycosis is an uncommon infectious disease caused predominantly by Actinomyces israelii. Actinomycosis usually involves the cervicofacial, thoracic, abdominal, and...
Actinomycosis is an uncommon infectious disease caused predominantly by Actinomyces israelii. Actinomycosis usually involves the cervicofacial, thoracic, abdominal, and pelvic region, dissemination is uncommon. Actinomyces viscosus are commensal organisms that make up the normal flora of the oropharynx of humans and has rarely been reported to cause disease. Here, we report a unique case of disseminated actinomycosis with lung and brain lesions caused by Actinomyces viscosus resembling lung cancer with metastasis in a 74 year old male. Cultures from skin lesions confirmed A. viscosus. Although the patient was immunocompromised, antibiotic treatment with a penicillin-based regimen was effective.
PubMed: 30181949
DOI: 10.1016/j.rmcr.2018.08.009 -
Advances in Clinical and Experimental... Feb 2019Actinomyces species have a low virulence and pathogenicity, but under specific circumstances they may be involved in root canal and periapical tissue infections. (Comparative Study)
Comparative Study
BACKGROUND
Actinomyces species have a low virulence and pathogenicity, but under specific circumstances they may be involved in root canal and periapical tissue infections.
OBJECTIVES
The aim of the study was to investigate the antibacterial activity of various root canal sealers on standardized strains of Actinomyces.
MATERIAL AND METHODS
The materials tested in this study included AH Plus™ Jet (AH), Apexit® Plus (AP), Endomethasone N (EN), GuttaFlow® (GF), Hybrid Root SEAL (HB), MTA Fillapex (FL), Real® Seal (RCS), Roeko Seal Automix (RSA), Sealapex™ (SP), and Tubli-Seal™ (TS). The antibacterial effect of the freshly mixed sealers on standardized strains of Actinomyces israelii NCTC 8047 and Actinomyces viscosus ATCC 15987 was evaluated with the use of the agar diffusion test (ADT). The results were obtained by measuring the diameter of the growth inhibition zone at 96 h and 1, 2, 3, and 4 weeks, and were analyzed in time using repeated measures analysis of variance (ANOVA). Statistically significant differences among the materials were determined by using one-way ANOVA and Tukey's post hoc testing. A paired Student's t-test was applied to compare the susceptibility of particular strains to each sealer. The critical level of significance for all tests was p < 0.05.
RESULTS
Most sealers demonstrated growth inhibition zones against both tested bacteria, except for RSA and GF. Actinomyces viscosus was significantly more susceptible than A. israelii to AP, RCS (p < 0.001) and TS (p = 0.012). Actinomyces israelii was significantly more susceptible than A. viscosus to EN, HB and SP (p < 0.001).
CONCLUSIONS
The antimicrobial effect of the examined materials varied considerably depending on the type of material and bacterial species tested. Most of the tested root canal sealers exhibited antibacterial activity on standardized strains of Actinomyces, with FL showing the highest antibacterial effect on both bacterial strains. Importantly, both standardized strains of Actinomyces were characterized by varied sensitivity to root canal sealers.
Topics: Actinomyces; Anti-Bacterial Agents; Colony Count, Microbial; Dental Pulp Cavity; Humans; Root Canal Filling Materials
PubMed: 30085427
DOI: 10.17219/acem/78022 -
PloS One 2018Recent developments in High-Throughput DNA sequencing (HTS) technologies and ancient DNA (aDNA) research have opened access to the characterization of the microbial...
Recent developments in High-Throughput DNA sequencing (HTS) technologies and ancient DNA (aDNA) research have opened access to the characterization of the microbial communities within past populations. Most studies have, however, relied on the analysis of dental calculus as one particular material type particularly prone to the molecular preservation of ancient microbial biofilms and potential of entire teeth for microbial characterization, both of healthy communities and pathogens in ancient individuals, remains overlooked. In this study, we used shotgun sequencing to characterize the bacterial composition from historical subjects showing macroscopic evidence of oral pathologies. We first carried out a macroscopic analysis aimed at identifying carious or periodontal diseases in subjects belonging to a French rural population of the 18th century AD. We next examined radiographically six subjects showing specific, characteristic dental pathologies and applied HTS shotgun sequencing to characterize the microbial communities present in and on the dental material. The presence of Streptococcus mutans and also Rothia dentocariosa, Actinomyces viscosus, Porphyromonas gingivalis, Tannerella forsythia, Pseudoramibacter alactolyticus, Olsenella uli and Parvimonas micra was confirmed through the presence of typical signatures of post-mortem DNA damage at an average depth-of-coverage ranging from 0.5 to 7X, with a minimum of 35% (from 35 to 93%) of the positions in the genome covered at least once. Each sampled tooth showed a specific bacterial signature associated with carious or periodontal pathologies. This work demonstrates that from a healthy independent tooth, without visible macroscopic pathology, we can identify a signature of specific pathogens and deduce the oral health status of an individual.
Topics: DNA, Ancient; DNA, Bacterial; Dental Caries; Female; France; Health Status; History, 18th Century; Humans; Male; Metagenomics; Microbiota; Oral Health; Paleodontology; Periodontitis; Rural Population
PubMed: 29768437
DOI: 10.1371/journal.pone.0196482 -
Journal of Oral Microbiology 2017The bovine milk protein osteopontin (OPN) may be an efficient means to prevent bacterial adhesion to dental tissues and control biofilm formation. This study sought to...
The bovine milk protein osteopontin (OPN) may be an efficient means to prevent bacterial adhesion to dental tissues and control biofilm formation. This study sought to determine to what extent OPN impacts adhesion forces and surface attachment of different bacterial strains involved in dental caries or medical device-related infections. It further investigated if OPN's effect on adhesion is caused by blocking the accessibility of glycoconjugates on bacterial surfaces. Bacterial adhesion was determined in a shear-controlled flow cell system in the presence of different concentrations of OPN, and interaction forces of single bacteria were quantified using single-cell force spectroscopy before and after OPN exposure. Moreover, the study investigated OPN's effect on the accessibility of cell surface glycoconjugates through fluorescence lectin-binding analysis. OPN strongly affected bacterial adhesion in a dose-dependent manner for all investigated species (, , subsp. , , , and ). Likewise, adhesion forces decreased after OPN treatment. No effect of OPN on the lectin-accessibility to glycoconjugates was found. OPN reduces the adhesion and adhesion force/energy of a variety of bacteria and has a potential therapeutic use for biofilm control. OPN acts upon bacterial adhesion without blocking cell surface glycoconjugates.
PubMed: 29081915
DOI: 10.1080/20002297.2017.1379826 -
Nefrologia : Publicacion Oficial de La... 2017
PubMed: 28750877
DOI: 10.1016/j.nefro.2017.01.001 -
PloS One 2017Dental caries is the most prevalent disease in humans globally. Efforts to control it have been invigorated by an increasing knowledge of the oral microbiome...
Dental caries is the most prevalent disease in humans globally. Efforts to control it have been invigorated by an increasing knowledge of the oral microbiome composition. This study aimed to evaluate the bacterial diversity in occlusal biofilms and its relationship with clinical surface diagnosis and dietary habits. Anamneses were recorded from thirteen 12-year-old children. Biofilm samples collected from occlusal surfaces of 46 permanent second molars were analyzed by 16S rRNA amplicon sequencing combined with the BLASTN-based search algorithm for species identification. The overall mean decayed, missing and filled surfaces modified index [DMFSm Index, including active white spot lesions (AWSL)] value was 8.77±7.47. Biofilm communities were highly polymicrobial collectively, representing 10 bacterial phyla, 25 classes, 29 orders, 58 families, 107 genera, 723 species. Streptococcus sp_Oral_Taxon_065, Corynebacterium matruchotii, Actinomyces viscosus, Actinomyces sp_Oral_Taxon_175, Actinomyces sp_Oral_Taxon_178, Actinomyces sp_Oral_Taxon_877, Prevotella nigrescens, Dialister micraerophilus, Eubacterium_XI G 1 infirmum were more abundant among surfaces with AWSL, and Streptococcus gordonii, Streptococcus sp._Oral_Taxon_058, Enterobacter sp._str._638 Streptococcus australis, Yersinia mollaretii, Enterobacter cloacae, Streptococcus sp._Oral_Taxon_71, Streptococcus sp._Oral_Taxon_F11, Centipeda sp._Oral_Taxon_D18 were more abundant among sound surfaces. Streptococcus mutans was detected on all surfaces in all patients, while Streptococcus sobrinus was detected only in three patients (mean relative abundances 7.1% and 0.6%, respectively). Neither species differentiated healthy from diseased sites. Diets of nine of the subjects were scored as high in fermentable carbohydrates (≧2X/day between meals). A direct association between relative abundances of bacteria and carbohydrate consumption was observed among 18 species. High consumption of fermentable carbohydrates and sound surfaces were associated with a reduction in bacterial diversity. PCoA plots displayed differences in bacterial community profiles between sound and diseased surfaces. Our study showed that, in addition to mutans streptococci, other species may be associated with the initiation of dental caries on occlusal surfaces, and that biofilm diversity of tooth surfaces is influenced by carbohydrate consumption and a surface's health status.
Topics: Bacteria; Brazil; Child; Cross-Sectional Studies; Dental Caries; Diet; Female; Humans; Male; Microbiota; Mouth; Surface Properties
PubMed: 28678838
DOI: 10.1371/journal.pone.0180621 -
Scientific Reports Dec 2016Controlling and reducing the formation of pathogenic biofilm on tooth surface is the key to the prevention and treatment of the biofilm-associated oral diseases....
Controlling and reducing the formation of pathogenic biofilm on tooth surface is the key to the prevention and treatment of the biofilm-associated oral diseases. Antimicrobial peptides (AMPs), considered as possible future alternatives for conventional antibiotics, have been extensively studied for the control of bacterial infection. Due to the rapid dilution and degradation by human saliva, AMP preparations designed for oral use with longer retention and higher efficacy are in urgent need. To this end, a hydroxyapatite (HAp)-binding antimicrobial peptide (HBAMP), which is based on the fusion of a specific HAp-binding heptapeptide (HBP7) domain and a broad-spectrum antimicrobial peptide (KSLW) domain, has been developed in our laboratory. HBAMP was supposed to form a contact-active antibacterial interface on tooth surface to inhibit the formation of biofilms. In this study, we investigated its binding behaviour, antibacterial activity against bacteria in both planktonic and sessile states, enzymatic stability in human saliva, and cytocompatibility to human gingival fibroblasts (HGFs). Our findings suggest that HBAMP could adsorb on tooth surface to provide effective antibacterial activity with improved retention. This study provides a proof-of-concept on using conjugated molecules to promote antibacterial efficacy by synergistically actions of HBAMP free in solution and bound on tooth surface.
Topics: Actinomyces viscosus; Amino Acid Sequence; Anti-Bacterial Agents; Antimicrobial Cationic Peptides; Biofilms; Cells, Cultured; Delayed-Action Preparations; Durapatite; Fibroblasts; Gingiva; Humans; Lactobacillus acidophilus; Microbial Sensitivity Tests; Plankton; Protein Binding; Saliva; Streptococcus mutans; Streptococcus sanguis
PubMed: 27910930
DOI: 10.1038/srep38410 -
Brazilian Oral Research Nov 2016The aim of this study was to assess the in vitro antimicrobial effects of chlorhexidine digluconate (CHX), polyhexamethylene biguanide (PHBM), and octenidine...
The aim of this study was to assess the in vitro antimicrobial effects of chlorhexidine digluconate (CHX), polyhexamethylene biguanide (PHBM), and octenidine dihydrochloride (OCT) on cariogenic microorganisms by using their minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC). CHX, PHBM, and OCT were diluted in distilled water to the final test concentrations. Using the in-tube dilution method, Streptococcus mutans, Lactobacillus acidophilus, Lactobacillus rhamnosus, and Actinomyces viscosus were cultivated on blood agar and Mueller-Hinton broth (MHB) at 37°C for 48 h. They were read using a spectrophotometer to detect MIC. To determine MBC, samples in the range of the turbidity threshold after 24 h were transferred onto blood agar and evaluated for growth after 24 h. Different MICs and MBCs were observed in all disinfectants against each microorganism. The lowest MIC and MBC against S. mutans (60 mg/L) were obtained from PHBM. The lowest values against L. rhamnosus (15 mg/L, 30 mg/L), A. viscosus (30 mg/L), and L. acidophilus (15 mg/L, 30 mg/L) were determined by OCT. PHBM and OCT have the potential to be replaced with CHX because they were effective against cariogenic microorganisms.
Topics: Agar; Anti-Bacterial Agents; Anti-Infective Agents, Local; Biguanides; Chlorhexidine; Dental Caries; Gram-Positive Bacteria; Imines; Microbial Sensitivity Tests; Pyridines; Reproducibility of Results; Spectrophotometry; Time Factors
PubMed: 27901206
DOI: 10.1590/1807-3107BOR-2016.vol30.0125 -
Frontiers in Microbiology 2016In oral health, the interdental spaces are a real ecological niche for which the body has few or no alternative defenses and where the traditional daily methods for...
In oral health, the interdental spaces are a real ecological niche for which the body has few or no alternative defenses and where the traditional daily methods for control by disrupting biofilm are not adequate. The interdental spaces are the source of many hypotheses regarding their potential associations with and/or causes of cardiovascular disease, diabetes, chronic kidney disease, degenerative disease, and depression. This PCR study is the first to describe the interdental microbiota in healthy adults aged 18-35 years-old with reference to the Socransky complexes. The complexes tended to reflect microbial succession events in developing dental biofilms. Early colonizers included members of the yellow, green, and purple complexes. The orange complex bacteria generally appear after the early colonizers and include many putative periodontal pathogens, such as Fusobacterium nucleatum. The red complex (Porphyromonas gingivalis, Tannerella forsythia, and Treponema denticola) was considered the climax community and is on the list of putative periodontal pathogens. The 19 major periodontal pathogens tested were expressed at various levels. F. nucleatum was the most abundant species, and the least abundant were Actinomyces viscosus, P. gingivalis, and Aggregatibacter actinomycetemcomitans. The genome counts for Eikenella corrodens, Campylobacter concisus, Campylobacter rectus, T. denticola, and Tannerella forsythensis increased significantly with subject age. The study highlights the observation that bacteria from the yellow complex (Streptococcus spp., S. mitis), the green complex (E. corrodens, Campylobacter gracilis, Capnocytophaga ochracea, Capnocytophaga sputigena, A. actinomycetemcomitans), the purple complex (Veillonella parvula, Actinomyces odontolyticus) and the blue complex (A. viscosus) are correlated. Concerning the orange complex, F. nucleatum is the most abundant species in interdental biofilm. The red complex, which is recognized as the most important pathogen in adult periodontal disease, represents 8.08% of the 19 bacteria analyzed. P. gingivalis was detected in 19% of healthy subjects and represents 0.02% of the interdental biofilm. T. forsythensis and T. denticola (0.02 and 0.04% of the interdental biofilm) were detected in 93 and 49% of healthy subjects, respectively. The effective presence of periodontal pathogens is a strong indicator of the need to develop new methods for disrupting interdental biofilm in daily oral hygiene.
PubMed: 27313576
DOI: 10.3389/fmicb.2016.00840