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Scanning electron microscopy image of Escherichia coli biofilm on Teflon. The arrows in the image point to the extracellular matrix enclosing the Escherichia coli biofilm bacteria (colored in pink). The scale bar in the image is 10 μm.
Source publication
Abiotic surfaces are vulnerable to bacterial adhesion and to biofilm formation. Therefore, it is necessary to understand the parameters that influence bacterial adhesion to find out solutions against cell adhesion and biofilm formation. The ability of pathogenic bacteria to adhere and to form biofilms on abiotic surfaces represents a major health s...
Context in source publication
Context 1
... formation is a complex process which gives bacteria a better resistance to cleaning agents than bacteria growing under planktonic form [7]. Biofilm is a community of microorganisms in which cells stick to a surface and to each other (Figure 1). This cell cluster is marked by the secretion of extracellular matrix (Figure 2) with adhesive and protective properties [1,7]. Biofilm formation requires different steps and there are a number of mechanisms by which many microbial species may come closely in contact with a surface, attach and promote cell-cell interactions in order to grow and form biofilms. ...
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Extracellular matrix stiffness comprises one of the multiple environmental mechanical stimuli that are well known to influence cellular behavior, function, and fate in general. Although increasingly more adherent cell types' responses to matrix stiffness have been characterized, how adherent cells' susceptibility to bacterial infection depends on m...
Background
The tumor-derived GL261 cell line is used as a model for studying glioblastoma and other high-grade gliomas, and can be cultured adherently or as free-floating aggregates known as neurospheres. These different culture conditions give rise to distinct phenotypes, with increased tumorigenicity displayed by neurosphere-cultured cells. An im...
Citations
... Furthermore, HAp has a high surface area and porosity, enabling it to adsorb organic pollutants and bacteria, fungi, and bioorganic molecules from contaminated water. The hydrophilic nature of HAp enhances microbial attachment, allowing bacteria to colonize the surface and initiate bio lm formation [8,9]. Meanwhile, solar steam generation systems operate under high humidity and heat, which can improve microbial proliferation rather than suppress it. ...
The increasing global demand for clean water has driven significant research into solar steam generation and water purification technologies. Hydroxyapatite (HAp), a biocompatible and chemically stable material, has demonstrated promise for water treatment due to its excellent adsorption properties. However, microbial contamination poses a significant challenge in its application for solar steam generation. Herein, a novel macroporous silver-doped hydroxyapatite (Ag-HAp) nanocomposite was used for the first time in fabricating photothermal membranes. The incorporation of Ag into Ag-HAp significantly alters its structure, introducing macroporous voids, which are excellent for water transportation and steam release in solar steam generation. The results show that the Ag-HAp membrane achieved an evaporation rate of 1.202 kgm − 2 h − 1 under one-sun illumination, a 1.33-fold increase compared to pure HAp membranes. Additionally, antibacterial evaluations using the disc diffusion method revealed significant antibacterial activity against Escherichia coli and Staphylococcus aureus , with inhibition zones increasing with Ag-HAp concentration. These findings highlight the potential of Ag-HAp nanocomposites as an efficient and durable solution for water harvesting and purification.
... Consequently, it is crucial to prioritize the development of innovative strategies and technologies aimed at preventing, controlling, and eliminating biofilms. This is essential for ensuring the safety and quality of food products throughout the entire production and storage process [7][8][9]. The review focuses on biofilm formation primarily in food processing environments, including biofilms growing on solid food products and equipment surfaces including storage tanks, reactors, and pipes. ...
... In the processing, storage, and distribution of food, a number of methods have been proposed to prevent and control the formation of biofilms [9,11,12]. These studies demonstrate that there is not a single, all-encompassing way to combat the threat posed by biofilms. ...
Understanding biofilm rheology is crucial for industrial and domestic food safety practices. This comprehensive review addresses the knowledge gap on the rheology of biofilm. Specifically, the review explores the influence of fluid flow, shear stress, and substrate properties on the initiation, structure, and functionality of biofilms, as essential implications for food safety. The viscosity and shear-thinning characteristics of non-Newtonian fluids may impact the attachment and detachment dynamics of biofilms, influencing their stability and resilience under different flow conditions. The discussion spans multiple facets, including the role of extracellular polymeric substances (EPSs) in biofilm formation, the impact of rheological attributes of biofilm on their adhesion to surfaces, and the influence of shear forces between biofilms and substrate’s surface characteristics on biofilm stability. Analytical techniques, encompassing rheometry, microscopy, and molecular biology approaches, are scrutinized for their contributions to understanding these interactions. The paper delves into the implications for the food industry, highlighting potential risks associated with biofilm formation and proposing strategies for effective control and prevention. Future research directions and the integration of rheological considerations into food safety regulations are underscored as pivotal steps in mitigating biofilm-related risks. The synthesis of microbiology, materials science, and engineering perspectives offers a multidimensional exploration of rheology–biofilm interactions, laying the groundwork for informed interventions in diverse industrial settings.
... It is commonly recognized that the QS system controls the formation of biofilms by bacteria [Hawas, 2022] , also referred to as AI-1 auto inducers and acyl-homoserine lactones [Sharma and Singh, 2020]. Biofilm-forming bacteria use AI-1 for intraspecific communication, but certain bacteria are also able to identify rival bacterial species in their surroundings [Khelissa et al., 2017]. The QS based on AHLs is essential for controlling global gene expression in Gram-negative bacteria inresponse to bacterial cell density. ...
Many bacteria use quorum sensing (QS) as a communication process to control gene expression in a population density-dependent way. It is essential for coordinating a number of bacterial behaviours, like the formation of biofilms, the synthesis of virulence factors, and the resistance to antibiotics. Numerous virulence components that aid in the establishment of an infection are what mediate a bacterium's infectiousness. Quorum sensing (QS), a mechanism of cell-cell communication, regulates the development of virulence factors such lectin, exotoxin, enterotoxin, fibronectin protein, etc., which helps the bacteria penetrate the host's defense barrier and increase their pathogenicity. The technique of limiting a bacteria's ability to spread in order to adapt to a host and surroundings while still having drawbacks is known as quiescence. The QS system is generally understood to be bacterial cells synthesizing and then sensing a signaling chemical that, depending on the cell population, causes certain response events that are known to be self-inducing. Quorum sensing drives the major bacterial behavior known as biofilm development. Microbial biofilms have been posing a serious threat to the contemporary healthcare system for the past few years, and as the human population becomes more populous, so does the likelihood of them becoming resistant to antibiotics. Infectious illness research is greatly impacted by biofilms, especially when it comes to infections linked to healthcare-associated indwelling devices including prosthetic joints, implants, artificial heart valves, and catheters. Microbial aggregation membranes, or biofilms, are created when microorganisms stick to the surfaces of both live and nonliving things. Significantly, the characteristics of biofilms shield microorganisms from external stresses and strengthen their resistance to antimicrobial treatments, adding to the toxicity and persistence of microorganisms. Thus, one aspect of the bacterial survival mechanism is the creation of biofilms. On the other hand, foodborne bacteria that form biofilms have the potential to significantly increase the risk of foodborne illness infections, which can have detrimental effects on the economy and public health. In healthy individuals, Klebsiella pneumoniae colonises mucosal surfaces and accounts for one-third of hospitalised patients' Gram-negative infections. It is possible for Klebsiella. pneumoniae to acquire antibiotic resistance elements, such as transposons and plasmids that encode different β-lactamases and efflux pumps. Antibiotic resistance is also caused by mutations in several proteins, including but not limited to β-lactamases, efflux proteins, outer membrane proteins, gene replication enzymes, protein synthesis complexes, and transcription enzymes.
... They pose a serious concern to food safety because they can proliferate, settle, and form biofilms on food surfaces [3]. Furthermore, one of the main causes of foodborne illness outbreaks is the unsanitary conditions of surfaces, tools, and processing areas that come into touch with food [4]. According to published research, eating food tainted with harmful bacteria like Staphylococcus aureus and Escherichia coli can be extremely harmful to one's health. ...
This study investigated the antimicrobial and antioxidant activity of clove (Syzygium aromaticum) and thyme (Thymus vulgaris) essential oils, which are traditionally used as food packaging materials. The essential oils were extracted using hydro distillation and their antimicrobial activity was evaluated against common foodborne pathogens, including Escherichia coli, Staphylococcus aureus, Salmonella enterica, and Listeria monocytogenes. The antioxidant activity was determined using the DPPH (2,2-dip). The study found that both clove and thyme essential oils exhibited antimicrobial activity against all four foodborne pathogens tested, with clove oil having the strongest activity. In addition, both essential oils showed antioxidant activity, with clove oil having the highest antioxidant capacity. Based on these results, clove and thyme essential oils have potential as natural food preservatives. This study provides further evidence of the beneficial properties of these two herbs and their potential use in food packaging. However, more research is needed to optimize the use of these essential oils and to ensure their safety and efficacy.
... Preserving a clean surface is crucial for applications in contact with water or moisture, as unchecked proliferation of bacteria, yeasts, or mold can occur [1][2][3][4]. However, the alternative of regular surface disinfection carries the potential risk of excessive chemical consumption, which could harm human health and the environment [5,6], underscoring the need for sustainable aseptic alternatives. ...
One method to reduce the spread of pathogens is to use clean surfaces. These have long-acting components, and their use would reduce the massive consumption of disinfectants and cleaning products. In order to ensure the safety of these surfaces in water-based systems and prevent mishandling and potential health and environmental risks, this study analyzed the stability of clean surfaces made of polyethylene with three silver compounds with different water solubility. The surfaces were subjected to erosion at 40 °C by immersing them in aqueous solutions of 3% acetic acid (w/v), 50% ethanol (v/v), and deionized water. The ionic silver release was monitored in real-time in situ via voltammetry using an Ag/S²⁻ electrode. Analytical methods such as Scanning Electron Microscopy (SEM) and Energy Dispersive X-ray Spectroscopy (EDS) were employed to elucidate the surface alteration. The plastic residue after immersion varied depending on the pH and the type of solvent used, with a higher plastic migration observed when in contact with the water-ethanol mixture. Furthermore, a correlation was identified between surface stability, oxygen composition in the antibacterial, and water solubility, influencing increased surface oxidation.
... Selection of biofilm treatment should consider the type of biofilm, environmental conditions, and presence of contaminants. It is crucial to minimize the environmental impact during biofilm treatment, and monitoring is key to ensure thorough biofilm removal without harming the environment [47]. ...
Biofilms are complex communities of microorganisms that can cause significant challenges in various settings, including industrial processes, environmental systems, and human health. The protective nature of biofilms makes them resistant to traditional anti‐biofilm strategies, such as chemical agents, mechanical interventions, and surface modifications. To address the limitations of conventional anti‐biofilm methods, researchers have explored emerging strategies that encompass the use of natural compounds, nanotechnology‐based methods, quorum‐sensing inhibition, enzymatic degradation, and antimicrobial photodynamic/sonodynamic therapy. There is an increasing focus on combining multiple anti‐biofilm strategies to combat resistance and enhance effectiveness. Researchers are continuously investigating the mechanisms of biofilm formation and developing innovative approaches to overcome the limitations of conventional anti‐biofilm methods. These efforts aim to improve the management of biofilms and prevent infections while preserving the environment. This study provides a comprehensive overview of the latest advancements in anti‐biofilm strategies. Given the dynamic nature of this field, exploring new approaches is essential to stimulate further research and development initiatives. The effective management of biofilms is crucial for maintaining the health of industrial processes, environmental systems, and human populations.
... The condition would be aggravated when the biofilms are recovered in the food and medical industry resulting in food-borne illnesses as well as healthcare-associated threats. Consequently, it is imperative to explore diverse approaches to mitigate bacterial adhesion and biofilm formation [51]. ...
Background
Bioinspired nanomaterials have widely been employed as suitable alternatives for controlling biofilm and pathogens due to their distinctive physico-chemical properties.
Methodology
This study explored the antibiofilm as well as photocatalytic potential of silver (Ag) nanoparticles (NPs) synthesized using the cell-free supernatant of Lactobacillus acidophilus for the disinfection of multi-drug-resistant (MDR) strains of enteroaggregative E. coli (EAEC), Salmonella Typhimurium, S. Enteritidis and methicillin-resistant Staphylococcus aureus (MRSA) on exposure to LED light. In addition, the removal of toxic cationic dyes i.e., methylene blue (MB), rhodamine B (RhB) and crystal violet (CV) was explored on exposure to sunlight, LED and UV lights.
Results
Initially, the synthesis of AgNPs was verified using UV- Vis spectroscopy, X-ray diffraction and transmission electron microscopy. The synthesized AgNPs exhibited MIC and MBC values of 7.80 and 15.625 µg/mL, respectively. The AgNPs exhibited significant inhibition (P < 0.001) in the biofilm-forming ability of all the tested MDR isolates. On exposure to LED light, the AgNPs could effectively eliminate all the tested MDR isolates in a dose-dependent manner. While performing photocatalytic assays, the degradation of RhB was observed to be quite slower than MB and CV irrespective of the tested light sources. Moreover, the sunlight as well as UV light exhibited better photodegradation capacity than LED light. Notwithstanding the light sources, RhB followed zero-order kinetics; however, MB and CV followed primarily second-order kinetics.
Conclusion
The green synthesized AgNPs were found to be an effective photocatalytic as well as antifouling candidate that could be applied in therapeutics and wastewater treatment.
... stage: due to various reasons such as mechanical disturbances, enzymatic decomposition of the matrix or the production of surfactant by cells, single cells separate from the biofilm, attach to the new surfaces and create the central nucleus of the new biofilm.These separated cells have changed in terms of resistance or pathogenicity compared to their free form(Goel et al., 2021;Khelissa et al., 2017;McDougald et al., 2012). ...
The formation of biofilm in different places and the failure to effectively remove it by the usual disinfection methods is due to its structure and the rich genetic resource available in it to deal with disinfectants. These impenetrable structures and diverse microbial genetics have caused biofilm pollution in different industries like the food industry, the medicine industry, the hospitals and the water distribution system, resulting in pathogenicity and reduction of industrial quality. An efficient way to deal with the resistant population of biofilm‐forming microbes is the use of hurdle technology including enzymes and essential oils. Enzymes reduce the resistance of the biofilm structure due to degradation of its extracellular polymer matrix (EPS) by their abilities to break down the organic molecules, and then the essential oils weaken the cells by penetrating the lipid membrane of the cell and destroying its integrity; as a result, the biofilm will be destroyed. The advantage of this hurdle technology is the environmental friendly of both methods, which reduces concerns about the use of chemical disinfection methods, but on the other hand, due to the sensitivity of enzymes as biological agents also the expensiveness of this technique and the considerations of working with essential oils as volatile and unstable liquids should abandon the routine methods of applying this disinfectant to biofilm and go for the microencapsulation method, which as a protective system increases the effectiveness of enzymes and essential oils as antibiofilm agents.
... Furthermore, biofilms can serve as reservoirs for pathogens and spoilage bacteria and to survive from cleaning and disinfection treatments. In fact, biofilmcontaminated equipment played a role in 59% of foodborne disease outbreaks evaluated in France (Khelissa et al., 2017). ...
... It has been proven that antimicrobial resistance to various conventional antibiotics is a rising concept. Also, biofilm (aggregation of bacteria together on living and non-living surfaces) is considered a severe problem in many fields such as food and marine industries leading to economic loss estimated at 77.7 billion United States dollars (Khelissa et al. 2017). Therefore, scientists have recently become in a constant search for new, natural and renewable sources with antimicrobial properties (Amin et al. 2015). ...
The world urgently needs to discover new drugs to meet the challenges that threaten human health. Marine molluscs are known as natural sources of various bioactive compounds. In the present study, to evaluate the biological activity of the marine snail Planaxis sulcatus, soft tissues of the snail were extracted using acetone (Me2CO), ethanol (EtOH) and ethyl acetate (EtOAc). All extracts were tested for their total antioxidant capacity, total phenolic and DPPH free radical scavenging activity. The extracts were also tested in vitro for their antimicrobial activities. The results showed that, EtOAc extract of P. sulcatus had the highest antioxidant capacity and total phenolic content, followed by acetone extract. Concerning antimicrobial and antibiofilm activities of tested extracts, EtOH extract showed a good antimicrobial and antibiofilm activity against Klebsiella pneumoniae, Staphylococcus aureus and Proteus vulgaris. The most promising extract, EtOH extract, was processed for cytotoxicity testing and GC–MS analysis based on antimicrobial testing. Ethanol extract revealed a significant cytotoxic effect against hepatocellular carcinoma (HePG-2) and colorectal colon cancer cell lines. GC–MS analysis indicated the presence of 41 compounds in the EtOH extract with hexadecanoic acid, ethyl ester and octadecanoic acid, ethyl ester as the main ingredients consisting 16.55% and 14.56% of the total content, respectively. These data suggest that P. sulcatus could be a good source for many compounds with antimicrobial and anticancer potentials.
