scholarly journals Antibacterial and Antibiofilm Effect of Low Viscosity Chitosan againstStaphylococcus epidermidis

2016 ◽  
Vol 2016 ◽  
pp. 1-7 ◽  
Author(s):  
Inger Sofie Dragland ◽  
Håkon Valen Rukke ◽  
Ida S. R. Stenhagen ◽  
Jessica Lönn-Stensrud ◽  
Hilde M. Kopperud
Keyword(s):  
Biofilm Formation ◽  
Direct Contact ◽  
Bactericidal Effect ◽  
Dependent Manner ◽  
Concentration Dependent Manner ◽  
Contact Test ◽  
Planktonic Growth ◽  
Low Viscosity ◽  
New Treatment ◽  
Direct Contact Test

Aim. The aim of this study was to investigate the antibacterial and antibiofilm properties of low viscosity chitosan onS. epidermidisgrowth and biofilm formation.Methods and Results. The antibacterial and antibiofilm properties were investigated, during both planktonic growth and biofilm formation. This was performed using different concentrations in media and by coating on polystyrene surfaces. In addition, the bactericidal effect was investigated using a modified direct contact test. The results showed that low viscosity chitosan in media had both a bacteriostatic and bactericidal effect on planktonic growth and biofilm formation ofS. epidermidisin a concentration dependent manner. Polystyrene discs coated with chitosan reduced both early biofilm formation (6 h) and late biofilm formation (18 h), as confirmed by scanning electron microscopy. The modified direct contact test showed a bactericidal effect.Conclusion. This study demonstrated that low viscosity chitosan has a bacteriostatic and bactericidal activity againstS. epidermidisand that the activity is dependent on the amount of chitosan added. In addition, low viscosity chitosan reduced biofilm formation both when added to media and when coated on polystyrene surfaces.Significance and Impact of Study. Low viscosity chitosan could be a contribution to new treatment approaches of biofilm-related infections ofS. epidermidis.

An Alanine-Rich Peptide Attenuates Quorum Sensing-Regulated Virulence and Biofilm Formation in Staphylococcus aureus

2019 ◽  
Vol 102 (4) ◽  
pp. 1228-1234 ◽  
Author(s):  
Raid Al Akeel ◽  
Ayesha Mateen ◽  
Rabbani Syed
Keyword(s):  
Gene Expression ◽  
Staphylococcus Aureus ◽  
Quorum Sensing ◽  
Biofilm Formation ◽  
Bacterial Attachment ◽  
The Body ◽  
Dependent Manner ◽  
Virulence Determinants ◽  
Microarray Gene Expression ◽  
Concentration Dependent Manner

Abstract Background: Alanine-rich proteins/peptides (ARP), with bioactivity of up to 20 amino acid residues, can be observed by the body easily during gastrointestinal digestion. Objective: Populus trichocarpa extract’s capability to attenuate quorum sensing-regulated virulence and biofilm formation in Staphylococcus aureus is described. Methods: PT13, an ARP obtained from P. trichocarpa, was tested for its activity against S. aureus using the broth microdilution test; a crystal-violet biofilm assay was performed under a scanning electron microscope. The production of various virulence factors was estimated with PT13 treatment. Microarray gene expression profiling of PT13-treated S. aureus was conducted and compared with an untreated control. Exopolysaccharides (EPS) was estimated to observe the PT13 inhibition activity. Results: PT13 was antimicrobial toward S. aureus at different concentrations and showed a similar growth rate in the presence and absence of PT13 at concentrations ≤8 μg/mL. Biofilm production was interrupted even at low concentrations, and biofilm-related genes were down-regulated when exposed to PT13. The genes encoding cell adhesion and bacterial attachment protein were the major genes suppressed by PT13. In addition, hemolysins, clumping activity, and EPS production of S. aureus decreased after treatment in a concentration-dependent manner. Conclusions: A long-chain PT13 with effective actions that, even at low concentration levels, not only regulated the gene expression in the producer organism but also blocked the virulence gene expression in this Gram-positive human pathogen is described. Highlights: We identified a PT13 as a potential antivirulence agent that regulated production of bacterial virulence determinants (e.g., toxins, enzymes and biofilm), downwards and it may be a promising anti-virulence agent to be further developed as an anti-infective agent.

scholarly journals Effect of Lonicera caerulea var. emphyllocalyx Fruit on Biofilm Formed by Porphyromonas gingivalis

2019 ◽  
Vol 2019 ◽  
pp. 1-9 ◽  
Author(s):  
Masaaki Minami ◽  
Hiroshi Takase ◽  
Mineo Nakamura ◽  
Toshiaki Makino
Keyword(s):  
Oral Cavity ◽  
Porphyromonas Gingivalis ◽  
Aspiration Pneumonia ◽  
Biofilm Formation ◽  
Bacterial Colonization ◽  
Bacterial Biofilm ◽  
Dependent Manner ◽  
Electron Microscopic ◽  
Concentration Dependent Manner ◽  
Lonicera Caerulea

Porphyromonas gingivalis is an important pathogenic anaerobic bacterium that causes aspiration pneumonia. This bacterium frequently forms biofilms in the oral cavity and in respiratory tract-associated medical devices. Bacterial colonization that occurs in association with this biofilm formation is the main reason for incurable aspiration pneumonia. The Lonicera caerulea var. emphyllocalyx (LCE) fruit has been used in folk medicine in Hokkaido, the northern part of Japan. The aim of this study was to elucidate one of the antimicrobial mechanisms of LCE methanol extract (LCEE)—the inhibitory effect of LCEE on biofilm formation by P. gingivalis. Our results show that LCEE significantly reduced biofilm formation by three different P. gingivalis isolates in a concentration- and time-dependent manner that were quantified by the adsorption of safranin red. When LCEE was added to biofilms already formed by P. gingivalis, LCEE did not degrade the biofilm. However, treatment with LCEE significantly promoted the removal of existing biofilm by vibration compared to that of control. We also confirmed biofilm formation in LCEE-treated P. gingivalis in tracheal tubes using scanning electron microscopic (SEM) analysis. Cyanidin 3-O-glucoside (C3G), one of the components of LCE, also inhibited the formation of biofilm by P. gingivalis in a concentration-dependent manner. Our results reveal that LCEE may be an effective antibacterial substance for P. gingivalis-induced aspiration pneumonia because of its role in the suppression of bacterial biofilm formation in the oral cavity.

scholarly journals PYED-1 Inhibits Biofilm Formation and Disrupts the Preformed Biofilm of Staphylococcus aureus

Antibiotics ◽  
2020 ◽  
Vol 9 (5) ◽  
pp. 240 ◽  
Author(s):  
Adriana Vollaro ◽  
Anna Esposito ◽  
Eliana Pia Esposito ◽  
Raffaele Zarrilli ◽  
Annalisa Guaragna ◽  
...  
Keyword(s):  
Staphylococcus Aureus ◽  
Quorum Sensing ◽  
Biofilm Formation ◽  
Surface Proteins ◽  
Transcriptional Analysis ◽  
Capsular Polysaccharides ◽  
Dependent Manner ◽  
Chronic Infections ◽  
Concentration Dependent Manner ◽  
Expression Of Genes

Pregnadiene-11-hydroxy-16α,17α-epoxy-3,20-dione-1 (PYED-1), a heterocyclic corticosteroid derivative of deflazacort, exhibits broad-spectrum antibacterial activity against Gram-negative and Gram-positive bacteria. Here, we investigated the effect of PYED-1 on the biofilms of Staphylococcus aureus, an etiological agent of biofilm-based chronic infections such as osteomyelitis, indwelling medical device infections, periodontitis, chronic wound infections, and endocarditis. PYED-1 caused a strong reduction in biofilm formation in a concentration dependent manner. Furthermore, it was also able to completely remove the preformed biofilm. Transcriptional analysis performed on the established biofilm revealed that PYED-1 downregulates the expression of genes related to quorum sensing (agrA, RNAIII, hld, psm, and sarA), surface proteins (clfB and fnbB), secreted toxins (hla, hlb, and lukD), and capsular polysaccharides (capC). The expression of genes that encode two main global regulators, sigB and saeR, was also significantly inhibited after treatment with PYED-1. In conclusion, PYED-1 not only effectively inhibited biofilm formation, but also eradicated preformed biofilms of S. aureus, modulating the expression of genes related to quorum sensing, surface and secreted proteins, and capsular polysaccharides. These results indicated that PYED-1 may have great potential as an effective antibiofilm agent to prevent S. aureus biofilm-associated infections.

scholarly journals In VitroEffects of Polyphosphate against Prevotella intermedia in Planktonic Phase and Biofilm

2015 ◽  
Vol 60 (2) ◽  
pp. 818-826 ◽  
Author(s):  
Eun-Young Jang ◽  
Minjung Kim ◽  
Mi Hee Noh ◽  
Ji-Hoi Moon ◽  
Jin-Yong Lee
Keyword(s):  
Biofilm Formation ◽  
Sodium Tripolyphosphate ◽  
Dilution Method ◽  
Agar Dilution Method ◽  
Prevotella Intermedia ◽  
Dependent Manner ◽  
Bacterial Cells ◽  
Concentration Dependent Manner ◽  
Content Type ◽  
Planktonic Phase

ABSTRACTPolyphosphate (polyP) has gained a wide interest in the food industry due to its potential as a decontaminating agent. In this study, we examined the effect of sodium tripolyphosphate (polyP3; Na5P3O10) against planktonic and biofilm cells ofPrevotella intermedia, a major oral pathogen. The MIC of polyP3 againstP. intermediaATCC 49046 determined by agar dilution method was 0.075%, while 0.05% polyP3 was bactericidal againstP. intermediain time-kill analysis performed using liquid medium. A crystal violet binding assay for the assessment of biofilm formation byP. intermediashowed that sub-MICs of polyP3 significantly decreased biofilm formation. Under the scanning electron microscope, decreased numbers ofP. intermediacells forming the biofilms were observed when the bacterial cells were incubated with 0.025% or higher concentrations of polyP3. Assessment of biofilm viability with LIVE/DEAD staining and viable cell count methods showed that 0.05% or higher concentrations of polyP3 significantly decreased the viability of the preformed biofilms in a concentration-dependent manner. The zone sizes of alpha-hemolysis formed on horse blood agar produced byP. intermediawere decreased in the presence of polyP3. The expression of the genes encoding hemolysins and the genes of the hemin uptake (hmu) locus was downregulated by polyP3. Collectively, our results show that polyP is an effective antimicrobial agent againstP. intermediain biofilms as well as planktonic phase, interfering with the process of hemin acquisition by the bacterium.

Role of Reduced Glutathione on Platelet Functions

1979 ◽  
Vol 42 (04) ◽  
pp. 1324-1331 ◽  
Author(s):  
Shigeyoshi Matsuda ◽  
Yasuo Ikeda ◽  
Makoto Aoki ◽  
Keisuke Toyama ◽  
Kiyoaki Watanabe ◽  
...  
Keyword(s):  
Direct Contact ◽  
Reduced Glutathione ◽  
Ultrastructural Observation ◽  
Dependent Manner ◽  
Clot Retraction ◽  
Concentration Dependent Manner ◽  
Inhibition Of Platelet Aggregation ◽  
Protein Thiols ◽  
Platelet Functions

SummaryThe role of reduced glutathione (GSH) on platelet functions was investigated utilizing thiol oxidizing agent, “diamide”. Diamide reacted rapidly with GSH in platelets, but not with protein thiols. Platelets treated with diamide showed inhibition of platelet aggregation induced by ADP, epinephrine and collagen in a concentration dependent manner. Clot retraction was grossly inhibited by diamide. Platelet interaction with polymerizing fibrin was examined by the method of Niewiarowski et al. (1972). There was no interaction observed between diamide-treated platelets and polymerizing fibrin. Ultrastructural observation of clots formed in the presence of diamide also showed no direct contact between platelets and fibrin strands. Platelets retained their granular contents, but showed loss of microtubules and dilatation of open canalicular system. Our findings may further support the idea that GSH plays an important role on platelet functions.

scholarly journals Fibrinogen-InducedStreptococcus mutansBiofilm Formation and Adherence to Endothelial Cells

2013 ◽  
Vol 2013 ◽  
pp. 1-8 ◽  
Author(s):  
Telma Blanca Lombardo Bedran ◽  
Jabrane Azelmat ◽  
Denise Palomari Spolidorio ◽  
Daniel Grenier
Keyword(s):  
Endothelial Cells ◽  
Infective Endocarditis ◽  
Biofilm Formation ◽  
Bacterial Species ◽  
Bactericidal Effect ◽  
Dependent Manner ◽  
Bacterial Cells ◽  
Human Fibrinogen ◽  
Polystyrene Support ◽  
The Impact

Streptococcus mutans, the predominant bacterial species associated with dental caries, can enter the bloodstream and cause infective endocarditis. The aim of this study was to investigateS. mutansbiofilm formation and adherence to endothelial cells induced by human fibrinogen. The putative mechanism by which biofilm formation is induced as well as the impact of fibrinogen onS. mutansresistance to penicillin was also evaluated. Bovine plasma dose dependently induced biofilm formation byS. mutans. Of the various plasma proteins tested, only fibrinogen promoted the formation of biofilm in a dose-dependent manner. Scanning electron microscopy observations revealed the presence of complex aggregates of bacterial cells firmly attached to the polystyrene support.S. mutansin biofilms induced by the presence of fibrinogen was markedly resistant to the bactericidal effect of penicillin. Fibrinogen also significantly increased the adherence ofS. mutansto endothelial cells. NeitherS. mutanscells nor culture supernatants converted fibrinogen into fibrin. However, fibrinogen is specifically bound to the cell surface ofS. mutansand may act as a bridging molecule to mediate biofilm formation. In conclusion, our study identified a new mechanism promotingS. mutansbiofilm formation and adherence to endothelial cells which may contribute to infective endocarditis.

Antibacterial Properties Evaluation of a Novel Polyurethane-Based Root Canal Sealer

2014 ◽  
Vol 804 ◽  
pp. 231-234
Author(s):  
Jian Wang ◽  
Ming Hui Zhao ◽  
Yu Bao Li ◽  
Yi Zuo ◽  
Bin Sun ◽  
...  
Keyword(s):  
Root Canal ◽  
Direct Contact ◽  
Antibacterial Properties ◽  
Adhesion Assay ◽  
Root Canal Sealer ◽  
Contact Test ◽  
Silver Phosphate ◽  
Application Potential ◽  
Rate Test ◽  
Direct Contact Test

Elimination of microorganisms from the root canal system and the prevention of subsequent reinfection are of importance for long-term endodontic treatment. The application of a sealer with antibacterial properties may reduce the reinfection and improve the success rate of the root filling treatment. The aim of this paper is to evaluate the antibacterial properties of a novel root canal sealer based on injectable self-curing polyurethane with silver phosphate (PU/Ag3PO4). The antibacterial abilities were assessed by direct contact test, anti-bacterial adhesion assay and bacteriostatic rate test. The results show that the fabricated PU/Ag3PO4sealer can completely inhibit the bacterial growth and prevent bacterial adhension effectively. The bacteriostatic rate is 93.6% and 98.1% when the bacteria incubated with PU/Ag3PO4 sealer for 7 and 24h respectively. The strong antibacterial abilities suggest that PU/Ag3PO4 sealer has great application potential in the field of root canal filling.Key words: Root canal sealer, polyurethane, silver phosphate, antibacterial properties, direct contact test

Antibacterial investigation of titanium-copper alloys using luminescent Staphylococcus epidermidis in a direct contact test

2019 ◽  
Vol 97 ◽  
pp. 707-714 ◽  
Author(s):  
Lee Fowler ◽  
Oscar Janson ◽  
Håkan Engqvist ◽  
Susanne Norgren ◽  
Caroline Öhman-Mägi
Keyword(s):  
Staphylococcus Epidermidis ◽  
Direct Contact ◽  
Copper Alloys ◽  
Contact Test ◽  
Direct Contact Test

Direct Contact Test for Evaluating Bacterial Growth on Machined and Rough Surface Implants

2017 ◽  
Vol 26 (6) ◽  
pp. 899-903 ◽  
Author(s):  
Shimshon Slutzkey ◽  
Ofer Moses ◽  
Haim Tal ◽  
Avi Meirowitz ◽  
Shlomo Matalon
Keyword(s):  
Rough Surface ◽  
Bacterial Growth ◽  
Direct Contact ◽  
Contact Test ◽  
Direct Contact Test

Antibacterial and antibiofilm effects of iron chelators against Prevotella intermedia

2013 ◽  
Vol 62 (9) ◽  
pp. 1307-1316 ◽  
Author(s):  
Ji-Hoi Moon ◽  
Cheul Kim ◽  
Hee-Su Lee ◽  
Sung-Woon Kim ◽  
Jin-Yong Lee
Keyword(s):  
Bacterial Growth ◽  
Biofilm Formation ◽  
Therapeutic Agent ◽  
Viable Cell ◽  
Iron Chelators ◽  
Prevotella Intermedia ◽  
Dependent Manner ◽  
Concentration Dependent Manner ◽  
Cell Counts ◽  
Strong Antimicrobial Activity

Prevotella intermedia, a major periodontopathogen, has been shown to be resistant to many antibiotics. In the present study, we examined the effect of the FDA-approved iron chelators deferoxamine (DFO) and deferasirox (DFRA) against planktonic and biofilm cells of P. intermedia in order to evaluate the possibility of using these iron chelators as alternative control agents against P. intermedia. DFRA showed strong antimicrobial activity (MIC and MBC values of 0.16 mg ml−1) against planktonic P. intermedia. At subMICs, DFRA partially inhibited the bacterial growth and considerably prolonged the bacterial doubling time. DFO was unable to completely inhibit the bacterial growth in the concentration range tested and was not bactericidal. Crystal violet binding assay for the assessment of biofilm formation by P. intermedia showed that DFRA significantly decreased the biofilm-forming activity as well as the biofilm formation, while DFO was less effective. DFRA was chosen for further study. In the ATP-bioluminescent assay, which reflects viable cell counts, subMICs of DFRA significantly decreased the bioactivity of biofilms in a concentration-dependent manner. Under the scanning electron microscope, P. intermedia cells in DFRA-treated biofilm were significantly elongated compared to those in untreated biofilm. Further experiments are necessary to show that iron chelators may be used as a therapeutic agent for periodontal disease.

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