Antibacterial Efficacy and Mechanism of Mannosylerythritol Lipids-A on Listeria monocytogenes

Mannosylerythritol lipids-A (MEL-A) is a novel biosurfactant with excellent surface activity and potential biomedical applications. In this study, we explored the antibacterial activity and the underlying mechanisms of MEL-A against the important food-borne pathogen Listeria monocytogenes. The bacterial growth and survival assays revealed a remarkable antibacterial activity of MEL-A. Since MEL-A is a biosurfactant, we examined the cell membrane integrity and morphological changes of MEL-A-treated bacteria by biochemical assays and flow cytometry analysis and electron microscopes. The results showed obvious damaging effects of MEL-A on the cell membrane and morphology. To further explore the antibacterial mechanism of MEL-A, a transcriptome analysis was performed, which identified 528 differentially expressed genes (DEGs). Gene ontology (GO) analysis revealed that the gene categories of membrane, localization and transport were enriched among the DEGs, and the analysis of the Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways demonstrated significant changes in the maltodextrin ABC transporter system and stress response system. Furthermore, the growth of L. monocytogenes could also be significantly inhibited by MEL-A in milk, a model of a real food system, suggesting that MEL-A could be potentially applied as an natural antimicrobial agent to control food-borne pathogens in the food industry.

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Dihydrochalcones in Malus inhibit bacterial growth by reducing cell membrane integrity

Food & Function ◽

10.1039/d0fo00037j ◽

2020 ◽

Vol 11 (7) ◽

pp. 6517-6527

Author(s):

Jinxiao Wang ◽

Ruijia Yang ◽

Zhengcao Xiao ◽

Qipeng Xu ◽

Pengmin Li ◽

...

Keyword(s):

Antibacterial Activity ◽

Cell Membrane ◽

Bacterial Growth ◽

Membrane Integrity ◽

Gram Negative Bacteria ◽

Gram Positive ◽

Gram Negative ◽

Cell Membrane Integrity

Dihydrochalcones in Malus had excellent antibacterial activity against both Gram-positive and Gram-negative bacteria.

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Toyoncin—a novel leaderless bacteriocin produced by Bacillus toyonensis XIN-YC13 that specifically targets B. cereus and Listeria monocytogenes

Applied and Environmental Microbiology ◽

10.1128/aem.00185-21 ◽

2021 ◽

Author(s):

Juanjuan Wang ◽

Haitao Xu ◽

Shu Liu ◽

Baolong Song ◽

Hualin Liu ◽

...

Keyword(s):

Antimicrobial Activity ◽

Listeria Monocytogenes ◽

Amino Acid ◽

Cell Membrane ◽

Membrane Damage ◽

Membrane Integrity ◽

Heat Stability ◽

Important Food ◽

Food Borne Pathogens ◽

Food Borne

Bacteriocins have attracted increasing interest because of their potential as natural preservatives. Recent studies showed that the Bacillus cereus group is a prominent producer of bacteriocins. Using a laboratory-based screening strategy, we identified a strain in the B. cereus group, B. toyonensis XIN-YC13, with antimicrobial activity against B. cereus. A novel, 70-amino acid-long leaderless bacteriocin, toyoncin, was purified from the culture supernatant of strain XIN-YC13 and its molecular mass was found to be 7817.1012 Da. Toyoncin shares no similarity with any other known bacteriocins, and its N-terminal amino acid is formylmethionine rather than methionine. Toyoncin shows good pH and heat stability and exhibits specific antimicrobial activity against two important food-borne pathogens, B. cereus and Listeria monocytogenes. Additionally, toyoncin exerts bactericidal activity and induces cell membrane damage. Toyoncin can also inhibit the outgrowth of B. cereus spores. The preservation assays showed that toyoncin effectively suppressed or eradicated B. cereus and L. monocytogenes in pasteurized skim milk. These results suggest that toyoncin can be used as a new bio-preservative against B. cereus and L. monocytogenes in the food industry. Importance: We identified a novel leaderless bacteriocin, toyoncin, produced by B. toyonensis XIN-YC13. Toyoncin shows good pH and heat stability; has specific antimicrobial activity against, B. cereus and L. monocytogenes (two important food-borne pathogens), and destroys their cell membrane integrity. Toyoncin inhibited the outgrowth of B. cereus spores and effectively inhibited or eliminated B. cereus and L. monocytogenes in a milk model system. These results indicate the potential of toyoncin as a food preservative.

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GC-MS/FID analysis, antibacterial activity and modes of action of essential oils from three Aframomum species found in Cameroon against foodborne pathogenic bacteria

Cameroon Journal of Experimental Biology ◽

10.4314/cajeb.v14i2.5 ◽

2021 ◽

Vol 14 (2) ◽

pp. 24-34

Author(s):

Gueaba Helene Mbuntcha ◽

Dongmo Hervet Paulin Fogang ◽

Armel Jackson Seukep ◽

Christine Schippa ◽

Elisabet Dunach ◽

...

Keyword(s):

Antibacterial Activity ◽

Cell Membrane ◽

Essential Oils ◽

Biofilm Formation ◽

Pathogenic Bacteria ◽

Membrane Integrity ◽

Cell Membrane Integrity ◽

Modes Of Action ◽

Alpha Pinene ◽

Foodborne Pathogenic Bacteria

Background: The current study examined the chemical profile and in vitro antibacterial activity of essential oils (EOs) extracted from Aframomum danielli (leaves and seeds), Aframomum chlamydentum (leaves), and Aframomum melegueta (leaves) against foodborne pathogenic bacteria. Methods: The hydro-distillation technique using a Clevenger-type apparatus was used to extract EOs, whereas the Gas Chromatography-Mass Spectrometry (GC-MS) and GC coupled to Flame Ionization Detector (GC-FID) allowed the chemical characterization of oil constituents. The broth micro-dilution method was applied for the determination of the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC). Besides, some modes of action were studied on the cell membrane integrity and biofilm formation of Salmonella typhi. Results: The major compounds identified from EOs of A. danielli seeds were eucalyptol (48.707%), limonene (11.368%), beta pinene (10.342-10.335%), and alpha terpineol (8.785-9.049%), whereas EOs from A. danielli leaves were dominated by sabinene (42.87%), beta pinene, (11.22%), caryophyllene (7.84%), terpinen-4-ol (5.68%), linalool (3.48%) and gamma terpinene (2.02%). Major volatile markers from EOs of A. chlamydentum leaves comprised beta pinene (49.72%), caryophyllene (10.62%), alpha pinene (6.21%) and linalool (2.96%), while those of EOs from A. melegueta included beta pinene (37.15%), caryophyllene (17.64%), caryophyllene oxide (8.72%) and alpha pinene (8.26%). This study is the first to report on the chemical constituents of EOs from A. chlamydentum. Test oils displayed significant antibacterial activity with the MIC ranging from 0.0625 to 0.5% (v/v). EOs from A. melegueta (leaves) appeared to be the most active, acting against all tested bacteria. All EOs identified displayed bactericidal effects against Citrobacter freundii, a bacterium known to cause a broad range of infections associated with a higher rate of in-hospital mortality. The EOs from A. melegueta may act through perturbation of cell membrane integrity and permeability as well as the inhibition of bacterial biofilm formation. Conclusion: Our findings suggest the possible application of essential oils in agricultural food products for the control of bacterial diseases.

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Shell thickness-dependent antibacterial activity and biocompatibility of gold@silver core–shell nanoparticles

RSC Advances ◽

10.1039/c7ra00485k ◽

2017 ◽

Vol 7 (19) ◽

pp. 11355-11361 ◽

Cited By ~ 20

Author(s):

Longping Yang ◽

Wenjing Yan ◽

Hongxia Wang ◽

Hong Zhuang ◽

Jianhao Zhang

Keyword(s):

Antibacterial Activity ◽

Cell Membrane ◽

Membrane Integrity ◽

Membrane Disruption ◽

Ag Nps ◽

Shell Nanoparticles ◽

Cell Membrane Integrity ◽

Gold Silver ◽

Cell Membrane Disruption ◽

Core Shell Nanoparticles

The Au@Ag NPs exhibit synergistically enhanced antibacterial activity and kill bacteria by affecting the cell membrane integrity or causing cell membrane disruption.

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Contractile Reserve, Microvascular Integrity and Cell Membrane Integrity for Predicting Contractile Recovery After Recanalization in Acute Myocardial Infarction

Journal of the American College of Cardiology ◽

10.1016/s0735-1097(97)84062-4 ◽

1998 ◽

Vol 31 (2) ◽

pp. 81A-82A

Author(s):

J Kwan

Keyword(s):

Myocardial Infarction ◽

Acute Myocardial Infarction ◽

Cell Membrane ◽

Membrane Integrity ◽

Contractile Reserve ◽

Cell Membrane Integrity ◽

Contractile Recovery

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Quercetin in attenuation of ischemic/reperfusion injury: A review

Current Molecular Pharmacology ◽

10.2174/1874467213666201217122544 ◽

2020 ◽

Vol 13 ◽

Author(s):

Milad Ashrafizadeh ◽

Saeed Samarghandian ◽

Kiavash Hushmandi ◽

Amirhossein Zabolian ◽

Md Shahinozzaman ◽

...

Keyword(s):

Cell Death ◽

Cell Membrane ◽

Blood Supply ◽

Apoptotic Cell ◽

Ischemia Reperfusion ◽

Membrane Integrity ◽

Therapeutic Effects ◽

Molecular Pathways ◽

Cell Membrane Integrity ◽

Cell Membrane Disruption

Background: Ischemia/reperfusion (I/R) injury is a serious pathologic event that occurs due to restriction in blood supply to an organ, followed by hypoxia. This condition leads to enhanced levels of pro-inflammatory cytokines such as IL-6 and TNF-, and stimulation of oxidative stress via enhancing reactive oxygen species (ROS) levels. Upon reperfusion, blood supply increases, but it deteriorates condition, and leads to generation of ROS, cell membrane disruption and finally, cell death. Plant derived-natural compounds are well-known due to their excellent antioxidant and anti-inflammatory activities. Quercetin is a flavonoid exclusively found in different vegetables, herbs, and fruits. This naturally occurring compound possesses different pharmacological activities making it appropriate option in disease therapy. Quercetin can also demonstrate therapeutic effects via affecting molecular pathways such as NF-B, PI3K/Akt and so on. Methods: In the present review, we demonstrate that quercetin administration is beneficial in ameliorating I/R injury via reducing ROS levels, inhibition of inflammation, and affecting molecular pathways such as TLR4/NF-B, MAPK and so on. Results and conclusion: Quercetin can improve cell membrane integrity via decreasing lipid peroxidation. Apoptotic cell death is inhibited by quercetin via down-regulation of Bax, and caspases, and upregulation of Bcl-2. Quercetin is able to modulate autophagy (inhibition/induction) in decreasing I/R injury. Nanoparticles have been applied for delivery of quercetin, enhancing its bioavailability and efficacy in alleviation of I/R injury. Noteworthy, clinical trials have also confirmed the capability of quercetin in reducing I/R injury.

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