ANTI-QUORUM SENSING POTENTIAL OF LIMONIA ACIDISSIMA (L.) AGAINST VIBRIO HARVEYI KUMB-VA4

Objective: This study aims to investigate the quorum-sensing inhibition (QSI) potential of Limonia acidissima L. against the biofilm forming Vibrio harveyi isolated from freshwater fish.Methods: The present study evaluated the anti-QS activity of the L. acidissima methanol and ethyl acetate (LA-M and LA-EA) fruit extracts using Chromobacterium violaceum ATCC 12472 (wild) and C. violaceum CV026 (mutant) as biomonitor strains and biofilm formation using the crystal violet assay. Vibrio sp. were isolated from freshwater-cultured fishes and screened for biofilm formation property. Strong biofilm forming isolate were subjected to molecular characterization. Limonia fruit pulp was subjected to methanol and ethyl acetate extraction using cold percolation method and yield was calculated. In parallel to determining the QSI properties of the extract, minimum inhibitory concentration (MIC), biofilm inhibition concentration (BIC), antibiofilm properties, and metabolic activity of LA-M and LA-EA against the biofilm forming V. harveyi KUMB-VA4 was determined.Results: The results of the present study demonstrated that the overall yield of methanol and ethyl acetate extract was 12.84% and 9.3% (w/w), respectively. Strong biofilm forming Vibrio isolate KUMB-VA4 was obtained from infected freshwater fishes and was subjected to molecular characterization. MIC of LA-M was 1510 μg/ml and LA-EA was observed to be 3000 μg/ml against the test pathogen, respectively. Biofilm inhibition assay revealed a BIC of LA-M at 250 μg/ml and LA-EA at 500 μg/ml. Both the plant extracts significantly reduced the biofilm formation of V. harveyi KUMB-VA4 and the metabolic activity in a dose-dependent manner. Light microscopy and scanning electron microscopy revealed that LA-M and LA-EA significantly altered 68.6% and 54.5% of the biofilm architecture at BIC. The QSI assay revealed that LA-M effectively reduced the violacein production of the biomonitor strains at sub-BIC (100–500 μg/ml) to 80% than LA-EA (43%) in a strong dose-dependent fashion.Conclusions: The present study revealed the QSI property of Limonia acidissima against the biofilm forming V. harveyi isolated from infected fish.

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Peptide Mix from Olivancillaria hiatula Interferes with Cell-to-Cell Communication in Pseudomonas aeruginosa

BioMed Research International ◽

10.1155/2019/5313918 ◽

2019 ◽

Vol 2019 ◽

pp. 1-12

Author(s):

Edward Ntim Gasu ◽

Hubert Senanu Ahor ◽

Lawrence Sheringham Borquaye

Keyword(s):

Pseudomonas Aeruginosa ◽

Quorum Sensing ◽

Biofilm Formation ◽

Antimicrobial Agents ◽

Cell Communication ◽

Microtiter Plate ◽

Antibiofilm Activity ◽

Dependent Manner ◽

Biofilm Inhibition ◽

Swarming Motility

Bacteria in biofilms are encased in an extracellular polymeric matrix that limits exposure of microbial cells to lethal doses of antimicrobial agents, leading to resistance. In Pseudomonas aeruginosa, biofilm formation is regulated by cell-to-cell communication, called quorum sensing. Quorum sensing facilitates a variety of bacterial physiological functions such as swarming motility and protease, pyoverdine, and pyocyanin productions. Peptide mix from the marine mollusc, Olivancillaria hiatula, has been studied for its antibiofilm activity against Pseudomonas aeruginosa. Microscopy and microtiter plate-based assays were used to evaluate biofilm inhibitory activities. Effect of the peptide mix on quorum sensing-mediated processes was also evaluated. Peptide mix proved to be a good antibiofilm agent, requiring less than 39 μg/mL to inhibit 50% biofilm formation. Micrographs obtained confirmed biofilm inhibition at 1/2 MIC whereas 2.5 mg/mL was required to degrade preformed biofilm. There was a marked attenuation in quorum sensing-mediated phenotypes as well. At 1/2 MIC of peptide, the expression of pyocyanin, pyoverdine, and protease was inhibited by 60%, 72%, and 54%, respectively. Additionally, swarming motility was repressed by peptide in a dose-dependent manner. These results suggest that the peptide mix from Olivancillaria hiatula probably inhibits biofilm formation by interfering with cell-to-cell communication in Pseudomonas aeruginosa.

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Genistein Inhibits the Pathogenesis of Aeromonas hydrophila by Disrupting Quorum Sensing Mediated Biofilm Formation and Aerolysin Production

Frontiers in Pharmacology ◽

10.3389/fphar.2021.753581 ◽

2021 ◽

Vol 12 ◽

Author(s):

Jing Dong ◽

Defu Zhang ◽

Jianrong Li ◽

Yongtao Liu ◽

Shun Zhou ◽

...

Keyword(s):

Quorum Sensing ◽

Aeromonas Hydrophila ◽

Biofilm Formation ◽

Cell Injury ◽

Foodborne Pathogen ◽

Opportunistic Pathogen ◽

Dependent Manner ◽

Novel Drugs ◽

Encoding Gene ◽

Dose Dependent

Aeromonas hydrophila is an opportunistic pathogen that is responsible for a variety of infectious diseases both in human and animals, particularly aquatic animals. Moreover, the pathogen has become a foodborne pathogen by transmitting from seafood to human. The abuse of antibiotics in aquaculture results in the emergence of antibiotic resistance and treatment failure. Therefore, novel approaches are urgently needed for managing resistant A. hydrophila associated infections. Aerolysin, an essential virulence factor of pathogenic A. hydrophila strain, has been identified as target developing novel drugs against pathogenesis of A. hydrophila. In the present study, genistein, without anti-A. hydrophila activity, was identified that could decrease the production of aerolysin and biofilm formation at a dose-dependent manner. Transcription of aerolysin encoding gene aerA and quorum sensing related genes ahyI and ahyR was significantly down-regulated when co-cultured with genistein. Cell viability studies demonstrated that genistein could significantly improve aerolysin mediated A549 cell injury. Furthermore, genistein could provide a remarkable protection to channel catfish infected with A. hydrophila. These findings indicate that targeting quorum sensing and virulence can be a useful approach developing drugs against A. hydrophila infections in aquaculture. Moreover, genistein can be chosen as a promising candidate in developing drugs against A. hydrophila.

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Optimization of Vibrio harveyi Luminometry Assay for Detecting Quorum Sensing Inhibitors

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.277-279.19 ◽

2005 ◽

Vol 277-279 ◽

pp. 19-22

Author(s):

Yeon Hee Kim ◽

Y. Kim ◽

Sung Hoon Park ◽

Jung Sun Kim

Keyword(s):

Quorum Sensing ◽

Vibrio Harveyi ◽

Homoserine Lactone ◽

Dependent Manner ◽

Wild Type ◽

Signal Molecule ◽

Homoserine Lactones ◽

Quorum Sensing Inhibitors ◽

Chain Lengths ◽

Dose Dependent

The luminometry assay using the wild-type Vibrio harveyi BB120 was evaluated as a possible detection method for quorum sensing inhibitors. The effects of the concentration of the quorum sensing signal molecule (AHL) as well as the cell density of the reporter strain and the different AHL analogues on luminescence expressed as relative light units (RLU) were examined. Inhibition of V. harveyi luminescence was observed in a dose dependent manner for all five AHL analogues. The RLU values exhibited linearity within the range of 2.9 x 102 ~ 3.2 x 105. Detection up to 102nM was possible for dodecanoyl-homoserine lactone and AHLs with alkyl chain lengths of C-8~C-14 were more active than the shorter chain-lengthed hexanoyl-homoserine lactones. Lipophilicity of the AHL seems to affect the sensitivity of the assay.

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Natural and Enantiopure Alkylglycerols as Antibiofilms Against Clinical Bacterial Isolates and Quorum Sensing Inhibitors of Chromobacterium violaceum ATCC 12472

Antibiotics ◽

10.3390/antibiotics10040430 ◽

2021 ◽

Vol 10 (4) ◽

pp. 430

Author(s):

Klauss E. Chaverra Daza ◽

Edelberto Silva Gómez ◽

Bárbara D. Moreno Murillo ◽

Humberto Mayorga Wandurraga

Keyword(s):

Quorum Sensing ◽

Biofilm Formation ◽

Microtiter Plate ◽

Resistance Mechanisms ◽

Chromobacterium Violaceum ◽

Dependent Manner ◽

Bacterial Isolates ◽

Concentration Dependent Manner ◽

Biofilm Inhibition ◽

Microtiter Plate Assay

Resistance mechanisms occur in almost all clinical bacterial isolates and represent one of the most worrisome health problems worldwide. Bacteria can form biofilms and communicate through quorum sensing (QS), which allow them to develop resistance against conventional antibiotics. Thus, new therapeutic candidates are sought. We focus on alkylglycerols (AKGs) because of their recently discovered quorum sensing inhibition (QSI) ability and antibiofilm potential. Fifteen natural enantiopure AKGs were tested to determine their effect on the biofilm formation of other clinical bacterial isolates, two reference strains and their QSI was determined using Chromobacterium violaceum ATCC 12472. The highest biofilm inhibition rates (%) and minimum QS inhibitory concentration were determined by a microtiter plate assay and ciprofloxacin was used as the standard antibiotic. At subinhibitory concentrations, each AKG reduced biofilm formation in a concentration-dependent manner against seven bacterial isolates, with values up to 97.2%. Each AKG displayed QSI at different levels of ability without affecting the growth of C. violaceum. AKG (2S)-3-O-(cis-13’-docosenyl)-1,2-propanediol was the best QS inhibitor (20 μM), while (2S)-3-O-(cis-9’-hexadecenyl)-1,2-propanediol was the least effective (795 μM). The results showed for the first time the QSI activity of this natural AKG series and suggest that AKGs could be promising candidates for further studies on preventing antimicrobial resistance.

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In VitroAnalyses of the Effects of Heparin and Parabens on Candida albicans Biofilms and Planktonic Cells

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.05061-11 ◽

2011 ◽

Vol 56 (1) ◽

pp. 148-153 ◽

Cited By ~ 15

Author(s):

Marisa H. Miceli ◽

Stella M. Bernardo ◽

T. S. Neil Ku ◽

Carla Walraven ◽

Samuel A. Lee

Keyword(s):

Candida Albicans ◽

Metabolic Activity ◽

Biofilm Formation ◽

High Dose ◽

Dependent Manner ◽

Planktonic Cells ◽

Content Type ◽

Heparin Sodium ◽

The Individual

ABSTRACTInfections and thromboses are the most common complications associated with central venous catheters. Suggested strategies for prevention and management of these complications include the use of heparin-coated catheters, heparin locks, and antimicrobial lock therapy. However, the effects of heparin onCandida albicansbiofilms and planktonic cells have not been previously studied. Therefore, we sought to determine thein vitroeffect of a heparin sodium preparation (HP) on biofilms and planktonic cells ofC. albicans. Because HP contains two preservatives, methyl paraben (MP) and propyl paraben (PP), these compounds and heparin sodium without preservatives (Pure-H) were also tested individually. The metabolic activity of the mature biofilm after treatment was assessed using XTT [2,3-bis-(2-methoxy-4-nitro-5-sulfophenyl)-2H-tetrazolium-5-carboxanilide] reduction and microscopy. Pure-H, MP, and PP caused up to 75, 85, and 60% reductions of metabolic activity of the mature preformedC. albicansbiofilms, respectively. Maximal efficacy against the mature biofilm was observed with HP (up to 90%) compared to the individual compounds (P< 0.0001). Pure-H, MP, and PP each inhibitedC. albicansbiofilm formation up to 90%. A complete inhibition of biofilm formation was observed with HP at 5,000 U/ml and higher. When tested against planktonic cells, each compound inhibited growth in a dose-dependent manner. These data indicated that HP, MP, PP, and Pure-H havein vitroantifungal activity againstC. albicansmature biofilms, formation of biofilms, and planktonic cells. Investigation of high-dose heparin-based strategies (e.g., heparin locks) in combination with traditional antifungal agents for the treatment and/or prevention ofC. albicansbiofilms is warranted.

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Biofilm inhibition and bactericidal activity of NiTi alloy coated with graphene oxide/silver nanoparticles via electrophoretic deposition

Scientific Reports ◽

10.1038/s41598-021-92340-7 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Sirapat Pipattanachat ◽

Jiaqian Qin ◽

Dinesh Rokaya ◽

Panida Thanyasrisung ◽

Viritpon Srimaneepong

Keyword(s):

Surface Roughness ◽

Silver Nanoparticles ◽

Graphene Oxide ◽

Electrophoretic Deposition ◽

Biofilm Formation ◽

Niti Alloy ◽

Surface Characteristics ◽

Dependent Manner ◽

Biofilm Inhibition ◽

Coating Time

AbstractBiofilm formation on medical devices can induce complications. Graphene oxide/silver nanoparticles (GO/AgNPs) coated nickel-titanium (NiTi) alloy has been successfully produced. Therefore, the aim of this study was to determine the anti-bacterial and anti-biofilm effects of a GO/AgNPs coated NiTi alloy prepared by Electrophoretic deposition (EPD). GO/AgNPs were coated on NiTi alloy using various coating times. The surface characteristics of the coated NiTi alloy substrates were investigated and its anti-biofilm and anti-bacterial effect on Streptococcus mutans biofilm were determined by measuring the biofilm mass and the number of viable cells using a crystal violet assay and colony counting assay, respectively. The results showed that although the surface roughness increased in a coating time-dependent manner, there was no positive correlation between the surface roughness and the total biofilm mass. However, increased GO/AgNPs deposition produced by the increased coating time significantly reduced the number of viable bacteria in the biofilm (p < 0.05). Therefore, the GO/AgNPs on NiTi alloy have an antibacterial effect on the S. mutans biofilm. However, the increased surface roughness does not influence total biofilm mass formation (p = 0.993). Modifying the NiTi alloy surface using GO/AgNPs can be a promising coating to reduce the consequences of biofilm formation.

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Inhibition of Biofilm Formation and Related Gene Expression of Listeria monocytogenes in Response to Four Natural Antimicrobial Compounds and Sodium Hypochlorite

Frontiers in Microbiology ◽

10.3389/fmicb.2020.617473 ◽

2021 ◽

Vol 11 ◽

Author(s):

Yunge Liu ◽

Lina Wu ◽

Jina Han ◽

Pengcheng Dong ◽

Xin Luo ◽

...

Keyword(s):

Listeria Monocytogenes ◽

Quorum Sensing ◽

Sodium Hypochlorite ◽

Biofilm Formation ◽

Natural Compounds ◽

Antimicrobial Compounds ◽

Natural Antimicrobial ◽

Low Degree ◽

Chemical Disinfectant ◽

Dose Dependent

The aim of this study was to assess the efficacy of four natural antimicrobial compounds (cinnamaldehyde, eugenol, resveratrol and thymoquinone) plus a control chemical disinfectant (sodium hypochlorite) in inhibiting biofilm formation by Listeria monocytogenes CMCC54004 (Lm 54004) at a minimum inhibitory concentration (MIC) and sub-MICs. Crystal violet staining assay and microscopic examination were employed to investigate anti-biofilm effects of the evaluated compounds, and a real-time PCR assay was used to investigate the expression of critical genes by Lm 54004 biofilm. The results showed that five antimicrobial compounds inhibited Lm 54004 biofilm formation in a dose dependent way. Specifically, cinnamaldehyde and resveratrol showed better anti-biofilm effects at 1/4 × MIC, while sodium hypochlorite exhibited the lowest inhibitory rates. A swimming assay confirmed that natural compounds at sub-MICs suppressed Lm 54004 motility to a low degree. Supporting these findings, expression analysis showed that all four natural compounds at 1/4 × MIC significantly down-regulated quorum sensing genes (agrA, agrC, and agrD) rather than suppressing the motility- and flagella-associated genes (degU, motB, and flaA). This study revealed that sub-MICs of natural antimicrobial compounds reduced biofilm formation by suppressing the quorum sensing system rather than by inhibiting flagella formation.

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

Journal of AOAC International ◽

10.5740/jaoacint.18-0251 ◽

2019 ◽

Vol 102 (4) ◽

pp. 1228-1234 ◽

Cited By ~ 1

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.

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Essential Oils of Aromatic Plants with Antibacterial, Anti-Biofilm and Anti-Quorum Sensing Activities against Pathogenic Bacteria

Antibiotics ◽

10.3390/antibiotics9040147 ◽

2020 ◽

Vol 9 (4) ◽

pp. 147 ◽

Cited By ~ 5

Author(s):

Marlon Cáceres ◽

William Hidalgo ◽

Elena Stashenko ◽

Rodrigo Torres ◽

Claudia Ortiz

Keyword(s):

Escherichia Coli ◽

Antimicrobial Activity ◽

Quorum Sensing ◽

Essential Oils ◽

Pathogenic Bacteria ◽

Bacterial Resistance ◽

Thymus Vulgaris ◽

Dependent Manner ◽

Concentration Dependent Manner ◽

Biofilm Inhibition

Both the ability of bacteria to form biofilms and communicate through quorum sensing allows them to develop different survival or virulence traits that lead to increased bacterial resistance against conventional antibiotic therapy. Here, seventeen essential oils (EOs) were investigated for the antimicrobial, antibiofilm, and anti-quorum sensing activities on Escherichia. coli O157:H7, Escherichia coli O33, and Staphylococcus epidermidis ATCC 12228. All essential oils were isolated from plant material by using hydrodistillation and analyzed by GC-MS. The antimicrobial activity was performed by using the microdilution technique. Subinhibitory concentrations of each EO were assayed for biofilm inhibition in both bacterial strains. Quantification of violacein in Chromobacterium violaceum CV026 was performed for the anti-quorum sensing activity. The cytotoxicity activity of the EOs was evaluated on Vero cell line by using MTT method. Thymol-carvacrol-chemotype (I and II) oils from Lippia origanoides and Thymus vulgaris oil exhibited the higher antimicrobial activity with MIC values of 0.37–0.75 mg/mL. In addition, these EOs strongly inhibited the biofilm formation and violacein (QS) production in a concentration-dependent manner, highlighting thymol-carvacrol-chemotype (II) oil as the best candidate for further studies in antibiotic design and development against bacterial resistance.

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Synthesis, In Silico, and In Vitro Evaluation of Long Chain Alkyl Amides from 2-Amino-4-Quinolone Derivatives as Biofilm Inhibitors

Molecules ◽

10.3390/molecules24020327 ◽

2019 ◽

Vol 24 (2) ◽

pp. 327 ◽

Cited By ~ 5

Author(s):

Mariana Espinosa-Valdés ◽

Sara Borbolla-Alvarez ◽

Ana Delgado-Espinosa ◽

Juan Sánchez-Tejeda ◽

Anabelle Cerón-Nava ◽

...

Keyword(s):

Quorum Sensing ◽

Biofilm Formation ◽

Active Sites ◽

Multidrug Resistant ◽

Health Concern ◽

Resistant Bacteria ◽

Biofilm Inhibition ◽

Amide Derivatives ◽

Long Chain

Infection from multidrug resistant bacteria has become a growing health concern worldwide, increasing the need for developing new antibacterial agents. Among the strategies that have been studied, biofilm inhibitors have acquired relevance as a potential source of drugs that could act as a complement for current and new antibacterial therapies. Based on the structure of 2-alkyl-3-hydroxy-4-quinolone and N-acylhomoserine lactone, molecules that act as mediators of quorum sensing and biofilm formation in Pseudomonas aeruginosa, we designed, prepared, and evaluated the biofilm inhibition properties of long chain amide derivatives of 2-amino-4-quinolone in Staphylococcus aureus and P. aeruginosa. All compounds had higher biofilm inhibition activity in P. aeruginosa than in S. aureus. Particularly, compounds with an alkyl chain of 12 carbons exhibited the highest inhibition of biofilm formation. Docking scores and molecular dynamics simulations of the complexes of the tested compounds within the active sites of proteins related to quorum sensing had good correlation with the experimental results, suggesting the diminution of biofilm formation induced by these compounds could be related to the inhibition of these proteins.

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