Embelia ribes Burm.f. fruit extract inhibit quorum sensing-dependent production of virulence factors and biofilm formation: An integrated in vitro and in silico approach

South African Journal of Botany, Journal Year: 2024, Volume and Issue: 165, P. 307 - 323

Published: Jan. 4, 2024

Language: Английский

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Complex Analysis of Vanillin and Syringic Acid as Natural Antimicrobial Agents against Staphylococcus epidermidis Biofilms

International Journal of Molecular Sciences, Journal Year: 2022, Volume and Issue: 23(3), P. 1816 - 1816

Published: Feb. 5, 2022

The presence of Staphylococcus epidermidis biofilms on medical devices is a major cause nosocomial diseases and infections. Extensive research directed at inhibiting the formation maturation such biofilms. Natural plant-derived phenolic compounds have promising antimicrobial effects against drug-resistant bacteria. anti-biofilm activity two selected (vanillin syringic acid) was tested three biofilm-forming methicillin-resistant S. strains with different genotypes. Resazurin assay combining crystal violet staining confocal microscopy used for biofilm extracellular polymer substance (EPS) inhibition tests. Effects EPS as proteins, DNA, polysaccharides were also examined. Combined quantitative real-time PCR agr quorum-sensing systems genetic determinants, our complex analysis vanillin acid showed similar strains, reducing up to 80% 55%, depending genotype strain. agents are thus potentially useful inhibitors

Language: Английский

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Alkyl Gallates as Potential Antibiofilm Agents: A Review

Molecules, Journal Year: 2023, Volume and Issue: 28(4), P. 1751 - 1751

Published: Feb. 12, 2023

Biofilms, which consist of microorganisms embedded in a polymer-rich matrix, contribute to variety infections and increase antimicrobial resistance. Thus, there is constant need develop new chemotherapeutic agents combat biofilms. This review article focuses on the use alkyl gallates, gallic acid its esters (methyl, ethyl, propyl, butyl, hexyl, octyl, dodecyl gallate), most are found plants, inhibit biofilm formation. The studies under reveal that gallates have capacity prevent development eradicate mature biofilms through mechanisms suppress synthesis extracellular polymeric quorum-sensing signaling, alter microbial cell membrane. effects stronger greater length chain. Moreover, gallates’ preventive activity against formation occurs at doses below minimum inhibitory concentration. More importantly, combining with antimicrobials or blue-light irradiation produces synergistic effect inhibition can be used treat overcome

Language: Английский

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N-acetylcysteine (NAC) attenuates quorum sensing regulated phenotypes in Pseudomonas aeruginosa PAO1

Heliyon, Journal Year: 2023, Volume and Issue: 9(3), P. e14152 - e14152

Published: Feb. 28, 2023

The expression of many virulence genes in bacteria is regulated by quorum sensing (QS), and the inhibition this mechanism has been intensely investigated. N-acetylcysteine (NAC) good antibacterial activity able to interfere with biofilm-related respiratory infections, but little known whether compound an effect on bacterial QS communication. This work aimed evaluate potential NAC as a inhibitor (QSI) Pseudomonas aeruginosa PAO1 through silico vitro analyses, well combination antibiotic tobramycin. Initially, molecular docking analysis was performed between regulatory proteins, LasR RhlR, P. NAC, 3-oxo-C12-HSL, C4-HSL, furanone C30. sub-inhibitory concentration determined growth curves. Then, we tests using reporter strains lasB-gfp rhlA-gfp, QS-related phenotypes. Finally, synergistic tobramycin calculated fractional inhibitory concentrations index (FICi) investigated against growth, pigment production, biofilm formation. In study, bound RhlR proteins similar manner AHL cognate, suggesting that it may be bind receptor vivo. biosensor assay, GFP signal turned down presence at 1000, 500, 250, 125 μM for rhlA-gfp (p < 0.05), effect. Pyocyanin rhamnolipids decreased 0.05) up 34 37%, respectively, μM. Swarming swimming motilities were inhibited 250 10000 Additionally, 2500 reduced NAC-tobramycin showed FICi 0.8, best 2500–1.07 μM, inhibiting formation 60%, besides reducing pyocyanin pyoverdine production. Confocal microscopy images revealed stronger, dense, compact control, while treated became thinner more dispersed. Overall, low promising anti-QS properties PAO1, adding its already antibiofilm agent.

Language: Английский

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Augmenting Neutrophil Extracellular Traps with Carbonized Polymer Dots: A Potential Treatment for Bacterial Sepsis

Small, Journal Year: 2024, Volume and Issue: 20(27)

Published: Jan. 26, 2024

Abstract Sepsis is a life‐threatening condition that can progress to septic shock as the body's extreme response pathogenesis damages its own vital organs. Staphylococcus aureus ( S. ) accounts for 50% of nosocomial infections, which are clinically treated with antibiotics. However, methicillin‐resistant strains (MRSA) have emerged and withstand harsh antibiotic treatment. To address this problem, curcumin (CCM) employed prepare carbonized polymer dots (CPDs) through mild pyrolysis. Contrary curcumin, as‐formed CCM‐CPDs highly biocompatible soluble in aqueous solution. Most importantly, induce release neutrophil extracellular traps (NETs) from neutrophils, entrap eliminate microbes. In an MRSA‐induced mouse model, it observed efficiently suppress bacterial colonization. Moreover, intrinsic antioxidative, anti‐inflammatory, anticoagulation activities resulting preserved functional groups precursor molecule on prevent progression severe sepsis. As result, infected mice show significant decrease mortality even oral administration. Histological staining indicates negligible organ damage MRSA‐infected CCM‐CPDs. It believed vivo studies presented herein demonstrate multifunctional therapeutic CPDs hold great potential against infectious diseases.

Language: Английский

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Cobalt-phenolic nanoparticles-driven self-assembly of hyaluronic acid hydrogels providing a multifactorial approach for chronic wound management

Chemical Engineering Journal, Journal Year: 2024, Volume and Issue: 494, P. 153064 - 153064

Published: June 12, 2024

Chronic wounds are persistent non-healing lesions whose complex management is due to the interplay of multiple factors promoting chronicity, such as oxidative stress, overexpressed enzyme activities impeding tissue repair and bacterial contamination. Currently marketed chronic wound dressings designed mainly absorb exudate, at most release antimicrobial agents, usually ionic silver. However, an effective requires addressing multifactorial nature in a holistic approach. This study explores potential metal phenolic network (MPN) nanoparticles (NPs), comprised epigallocatechin gallate (EGCG) cobalt, active agents structural elements dressings. The MPN NPs were able generate reactive oxygen species (ROS), disturb membrane, inhibit biofilm both gram-positive Staphylococcus aureus gram-negative Pseudomonas aeruginosa. Owing high interfacial activity their shells, drove self-assembly thiolated hyaluronic acid (THA) hydrogels featuring injectability, self-healing, stimuli-responsive delivery microenvironment, control over deleterious activities, stress colonisation. Specifically, inhibited matrix metalloproteinases (MMPs) myeloperoxidase (MPO) by 60 80 %, respectively, achieved 4-log reduction S. 2-log P. aeruginosa concentrations. Finally, in-vivo validated mouse animal model, showing lack toxicity similar healing efficiency antibiotic-containing commercial product.

Language: Английский

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Recent advances in the use of resveratrol against Staphylococcus aureus infections (Review)

Medicine International, Journal Year: 2024, Volume and Issue: 4(6)

Published: Aug. 30, 2024

As a notorious bacterial pathogen, Staphylococcus aureus (S. aureus) can readily induce infections in the community and hospital, causing significant morbidity mortality. With extensive rise of multiple resistance, conventional antibiotic therapy has rapidly become ineffective for related infections. Resveratrol is naturally occurring polyphenolic substance that been demonstrated to have effective antimicrobial activity against S. aureus. at sub‑inhibitory doses suppress expression virulence factors, contributing attenuated biofilm formation, interference with quorum sensing inhibition production toxins. promising efflux pump inhibitor, resveratrol enhances susceptibility certain extent. In conjunction antibiotics, displays unique synergistic effects norfloxacin aminoglycoside on S. aureus, yet antagonizes lethal daptomycin, oxacillin, moxifloxacin levofloxacin. Nevertheless, given low oral bioavailability resveratrol, advanced formulations need be developed delay rapid metabolism conversion or inactive conjugates. The present review discusses antibacterial properties aureus, an aim provide in‑depth insight researchers address challenges resistance.

Language: Английский

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Valorization of Lychee (Litchi chinensis) Processing Residues (Peel and Seed) Through Incorporation into Poly(vinyl alcohol)-Based Films for Use in Packaging

Waste and Biomass Valorization, Journal Year: 2025, Volume and Issue: unknown

Published: April 3, 2025

Language: Английский

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Synergistic effect of hyperoside and amentoflavone found in cashew leaf crude extract and potassium sorbate on inhibition of food spoilage bacteria

Journal of Agriculture and Food Research, Journal Year: 2025, Volume and Issue: unknown, P. 101886 - 101886

Published: April 1, 2025

Language: Английский

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Phenolic-Rich Wine Pomace Extracts as Antioxidant and Antipathogenic Agents Against Pseudomonas aeruginosa

Antibiotics, Journal Year: 2025, Volume and Issue: 14(4), P. 384 - 384

Published: April 5, 2025

Background/Objectives: Wine pomace is a rich source of bioactive phenolic compounds with potential health benefits. This study aimed to evaluate the antipathogenic and antioxidant properties ethanol ethyl acetate extracts from wine three grape varietals (Tannat, Bonarda, Malbec) explore their as natural alternatives for mitigating bacterial virulence in Pseudomonas aeruginosa. Methods: Successive exhaustion extractions were performed using solvents increasing polarity (ethyl ethanol). The content was quantified, activity evaluated standard assays. against P. aeruginosa assessed by measuring biofilm formation, elastase protease activity, pyocyanin production, swarming motility. Quorum sensing (QS) inhibition tested violacein production assay Chromobacterium violaceum. Results: Ethanol more effective at extracting compounds, Tannat exhibiting highest total (162.5 µg GAE/mg). HPLC-DAD analysis identified 16 acids, 18 flavonoids, 3 stilbenes across extracts. showed strong (phosphomolybdenum reducing capacity 67–128 μg AAE/mg, ABTS•+ scavenging 37–71 µg/mL, Fe3+ power 31–68 µg/mL) inhibited formation (up 61%), 41%), 46%) activities also reduced 78%) motility 68%), suggesting interference QS. Moreover, C. violaceum, confirming QS 26%). Conclusions: Among extracts, ethanol-extracted most substantial activities. results add value its use capable controlling without promoting development resistance.

Language: Английский

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