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[Display omitted] • CTC achieved a maximum of 97.8% removal in the MMT-CS bio-enhanced process. • MMT-CS promoted EPS secretion and electron transfer in the system. • The mechanism of bio-enhanced degradation of CTC by MMT-CS was revealed. • Paracoccus and Terrimonas were the key bacteria gene in MMT-CS bio-enhanced process. • The biological metabolic pathways of CTC were clarified. The efficient degradation of antibiotics holds significant implications for mitigating environmental pollution. This study synthesized a montmorillonite chitosan composite material (MMT-CS) using the gel template method. Subsequently, a bio-enhanced reactor was constructed to facilitate the degradation of chlorotetracycline (CTC). The addition of MMT-CS composite material enables the degradation of different concentrations of CTC. MMT-CS, a conductive carrier, effectively promotes microbial adhesion and boosts the metabolic activity of functional microorganisms. Additionally, it facilitates the maintenance of microbial activity under CTC pressure by promoting the secretion of extracellular polymeric substances, increasing critical enzyme activity, and enhancing the electron transfer capacity within the system. In this MMT-CS bio-enhanced process, Paracoccus (11.4%) and Bacillus (3.9%) are utilized as essential bacteria genes. The results of metabolic pathways prediction indicated significant enhancements in membrane-transport, nucleotide-metabolism, replication-repair, and lipid-metabolism. Thus, the developed self-supporting MMT-CS bio-enhanced process ensured the stability of the system during the removal of antibiotics. [ABSTRACT FROM AUTHOR]

In this investigation, microbial adhesion expedites formation and alteration of aluminous minerals within aviation fuel tank systems. The corrosion mechanisms of two uncoated aluminium alloys and three types of coating-pretreated aluminium alloys by hydrocarbon-degrading Shewanella algae are examined. NO 3 - reduction of microorganisms induces corrosion acceleration of LY12 aluminium alloy (1.48 g*m−2*h−1) and corrosion inhibition of 7B04 aluminium alloy. CLSM and SEM observation of coating morphology highlight the microbial deterioration behaviors of coatings (pitting, swelling, and peeling). It inspires material selection and surface coating of microbial corrosion protection of aluminium alloy in marine and aerial environments. • First report on hydrocarbon-degrading Shewanella algae corrosion. • Coated materials deterioration characterization through CLSM and EDS. • Microbial corrosion acceleration and inhibition rely on interface properties. • NO 3 - degradation affects interaction between microbial attachment and rust formation. • Universal linked cells on aluminium surface show tolerance of toxicity. [ABSTRACT FROM AUTHOR]

Quaternary ammonium salts (QAS) are widely used in medicine, industry and agriculture as disinfectants, biocides, and fungicides. QAS have the ability to coat various surfaces, prevent adhesion of microorganisms to them and inhibit the formation of biofilm. A group of surfactants derived from benzoic acid with different chemical structures was tested: monomeric QAS with different alkyl chain lengths (C 12 , C 14 , C 16), gemini QAS containing 12-carbon alkyl chains and linkers of various lengths (3,4,6 methylene groups), as well as multifunctional QAS. Among the tested surfactants, monomeric QAS showed the highest bactericidal and fungicidal activity. All three groups of tested compounds inhibited the filamentation of C. albicans. The best antimicrobial activity was demonstrated by the monomeric surfactant C 12 AA, while the multifunctional equivalent (2xC 12 AA) was characterized by good anti-adhesive activity. All tested compounds are non-mutagenic and cause low hemolysis of sheep erythrocytes. Multifunctional and gemini surfactants are also non-toxic. [Display omitted] • Monomeric surfactants show strong activity against planktonic bacteria and fungi. • Multifunctional surfactant was characterized by good anti-adhesive activity. • Monomeric and gemini quaternary ammonium salts inhibit Candida albicans filamentation. • Gemini and monomeric quaternary ammonium salts are non-mutagenic. • Quaternary ammonium salts induce low hemolysis of sheep erythrocytes. [ABSTRACT FROM AUTHOR]

This study investigates the field of antifouling membranes for water filtration and desalination applications, specifically focusing on two-dimensional materials. The study examines the importance of these membranes in the context of climate change and its effects on coastal ecosystems. The occurrence of biofouling in seawater desalination membranes is closely connected to intricate processes influenced by factors such as water quality, microbial communities, hydrodynamics, and membrane properties. Microorganism adhesion initiates the process, which then advances into irreversible attachment and the creation of biofilm. Detached pieces contribute to the perpetuation of fouling. Biofouling is caused by a variety of biomaterials and organics, including bacteria, extracellular polymeric substances (EPS), proteins, and humic compounds. Innovative methods such as surface alterations using two-dimensional materials like graphene and graphene oxide, as well as the use of biofouling-resistant materials, provide promising possibilities. These materials have antifouling characteristics, making them environmentally beneficial options that reduce the need for chemical cleaning. Their application improves the water treatment process by preventing fouling and enhancing membrane performance. Real-world research applications can enhance and optimize these tactics to effectively reduce biofouling in seawater desalination systems, hence improving efficiency and sustainability. This is particularly important in light of climate change and its impact on coastal ecosystems. The findings obtained from the literature review emphasise the utmost significance of tackling biofouling in the face of a changing environment, particularly with regard to microorganisms. Important factors to consider are the selection of coating materials, the implementation of environmentally friendly cleaning solutions made from natural chemicals, and the improvement of pretreatment systems. Green cleaning agents are important eco-friendly alternatives to typical biocides, as they possess antibacterial, antifungal, and antifouling capabilities. Given the existence of climate change, these observations serve as a basis for promoting environmentally friendly methods in water treatment technology. • The crucial role of membrane technology in fouling, climate change mitigation and environmental resilience. • The crucial role of membrane in mitigation for biofouling has been critically analyzed. • Efficiency, cost, and benefits of membranes for biofouling in membrane-based system. • Preventing biofouling in seawater desalination membranes using two-dimensional materials. [ABSTRACT FROM AUTHOR]

[Display omitted] • Static magnetic field (SMF) significantly accelerated aerobic granulation. • SMF promoted enhanced hydrophobic interactions and weakened electrostatic repulsion. • SMF led to a lower energy barrier to microbial aggregation. • SMF induced microorganisms to secrete highly hydrophobic and more adherent EPS. • SMF enhanced metabolic pathways for EPS production. Aerobic granulation promoted by static magnetic field had been widely noticed because of its environmental friendliness and economic feasibility. The mechanism of strengthening aerobic granulation by static magnetic field needed to be clarified. Consequently, this study aspired to promote aerobic granulation by loading different intensities of static magnetic fields (R1: 0 mT, R2: 10 mT, R3: 50 mT), and elucidate the potential mechanism of static magnetic fields enhancement in terms of microbial interactions, chemical structure and adhesion performance of extracellular polymeric substances (EPS), metabolic pathways. Compared to R1 (day 45), R3 and R2 completed granulation at day 34 and day 42 respectively. Under the influence of magnetic fields, the interfacial adsorption free energy between microorganisms decreased from −55.88 mJ/m2 (R1) to −64.32 mJ/m2 (R2) and −75.02 mJ/m2 (R3), and the energy barriers preventing microbial aggregation in R2 and R3 were reduced. This was attributed to the fact that magnetic fields induced microorganisms to secrete highly hydrophobic EPS and enhanced adhesion to metal cations (Ca2+, Mg2+, etc.), resulting in an enhanced hydrophobic interaction and a reduced electrostatic repulsion interaction between microorganisms. Furthermore, magnetic fields increased the relative abundance of EPS-producing bacteria (Chryseobacterium , Candidatus_Competibacter , Thauera , Zoogloea) and upregulated the abundance of functional genes associated with the synthesis of hydrophobic amino acids (trpA , trpB , ADT , ilvE , proC , metH) and energy supply (mdh , cs , acn , IDH , sucA , frdA). The above results proved that the static magnetic field promoted aerobic granulation by enhancing microbial aggregation and adhesion, which provided sufficient theoretical support for the construction of a new wastewater treatment plant. [ABSTRACT FROM AUTHOR]

Microbial cells secrete extracellular polymeric substances (EPS) to adhere to material surfaces, if they get in contact with solid materials such as metals. After phase equilibrium, microorganisms can adhere firmly to the metal surfaces causing metal dissolution and corrosion. Attachment and adhesion of microorganisms via EPS increase the possibility and the rate of metal corrosion. Many components of EPS are electrochemical and redox active, making them closely related to metal corrosion. Functional groups in EPS have specific adsorption ability, causing them to play a key role in biocorrosion. This review emphasizes EPS properties related to metal corrosion and protection and the underlying microbially influenced corrosion (MIC) mechanisms. Future perspectives regarding a comprehensive study of MIC mechanisms and green methodologies for corrosion protection are provided. [ABSTRACT FROM AUTHOR]

Introduction: Dental biofilm is a complex structure formed from the adhesion of various microbial cells to the film acquired on the dental structure. These cells adhere to each other while synthesizing an extracellular matrix, becoming a highly organized community, which makes it difficult to remove and promotes resistance to antimicrobials. The presence of Staphylococcus aureus in the oral biofilm can cause an disturb in the microbiota, facilitating the beginning of a disease process. Aim: To evaluate the non-adherent ability of Eucalyptus globulus and Eucalyptus citriodora against Staphylococcus aureus strains. Results: It was possible to observe that the essential oil of Eucalyptus globulus inhibited the formation of the biofilm with a Minimum Adhesive Inhibitory Concentration (MAIC) similar to 0.12 % chlorhexidine digluconate, both of 1:8. The essential oil of Eucalyptus citriodora did not prevent bacterial adherence to the tube walls in any evaluated concentration. Conclusion: Only the essential oil of the species Eucalyptus globulus has nonadherent activity against Staphylococcus aureus and can be used as an alternative product to control the biofilm. [ABSTRACT FROM AUTHOR]

Microbial adhesion to medical devices is common for hospital-acquired infections, particularly for urinary catheters. If not properly treated these infections cause complications and exacerbate antimicrobial resistance. Catheter use elicits bladder inflammation, releasing host serum proteins, including fibrinogen (Fg), into the bladder, which deposit on the urinary catheter. Enterococcus faecalis uses Fg as a scaffold to bind and persist in the bladder despite antibiotic treatments. Inhibition of Fg-pathogen interaction significantly reduces infection. Here, we show deposited Fg is advantageous for uropathogens E. faecalis, Escherichia coli, Pseudomonas aeruginosa, K. pneumoniae, A. baumannii, and C. albicans, suggesting that targeting catheter protein deposition may reduce colonization creating an effective intervention for catheter-associated urinary tract infections (CAUTIs). In a mouse model of CAUTI, host-protein deposition was reduced, using liquid-infused silicone catheters, resulting in decreased colonization on catheters, in bladders, and dissemination in vivo. Furthermore, proteomics revealed a significant decrease in deposition of host-secreted proteins on liquid-infused catheter surfaces. Our findings suggest targeting microbial-binding scaffolds may be an effective antibiotic-sparing intervention for use against CAUTIs and other medical device infections. [ABSTRACT FROM AUTHOR]

A microbial fuel cell (MFC) was constructed with CNTs, 0.02gMnO2/CNTs and 0.03gMnO2/CNTs modified graphite anode prepared by coating for enhancing copper wastewater treatment. The SEM, XRD and FTIR results showed that MnO2/CNTs and CNTs were successfully attached to the graphite electrode, indicating that the electrode was modified successfully. The surface wettability test showed that the decrease of the contact angle of the modified anode led to the increase of hydrophilicity, which was more conducive to microbial adhesion. The surface contact angle of CNTs modified electrode was the smallest, which was 11.17°. The maximum output voltage, power density and copper removal rate of 0.03gMnO2/CNTs modified anode MFC were 0.67 V, 1044.21 mW/m² and 98.93% respectively, which were 52.3%, 466.3% and 50.5% higher than those of unmodified anode. XPS results showed that the reduction products were Cu2O and Cu. Meanwhile, high throughput sequencing showed that CNTs and MnO2 could improve the richness and diversity of microbial community. MnO2/CNTs modified-anode accelerated the enrichment of electro-active bacteria such as Proteobacteria, Firmicutes and Bacteroidetes. [ABSTRACT FROM AUTHOR]

BACKGROUND Adhesion is considered important for Lactiplantibacillus to persist in the human gut and for it to exert probiotic effects. Lactiplantibacillus plantarum contains a considerable number and variety of genes encoding bile salt hydrolases (bsh), but their effects on microbial adhesion remain poorly understood. To clarify the effects of four bsh on adhesion, we tried to knock out bsh (Δbsh) of L. plantarum AR113 using the CRISPR‐Cas9 method, and compared the growth, auto‐aggregation (RAA), co‐aggregation (RCA), surface hydrophobicity (AHC) of AR113 wild‐type and Δbsh strains and their adhesion abilities to HT29 cells. RESULTS: We first obtained the AR113 Δbsh1,3,2,4 strain with four bsh knocked out. Their growth was significantly slower than the wild‐type strain cultured in De Man, Rogosa, and Sharpe medium (MRS) with 3.0 g L−1 glyco‐ or tauro‐conjugated bile acid. Bsh had no significant effect on the growth of ten strains cultured in MRS, but Δbsh1 inhibited their growth when cultured in MRS containing 3.0 g L−1 sodium glycocholate, whereas Δbsh4 instead promoted their growth in MRS with 3.0 g L−1 sodium glycocholate and sodium taurocholate. RCA and RAA were linearly positive for all strains except AR113 Δbsh2,4, and AHC and RAA were negatively correlated for most strains excluding AR113 Δbsh2, with RAA = 6.38–25.05%, RCA = 5.17–9.22%, and ACH = 3.22–47.71%. The adhesion ability of ten strains cultured in MRS was higher than that of strains cultured in MRS with 3.0 g L−1 bovine bile, and it was related to bsh2. CONCLUSION: Bsh differentially affected the adhesion of AR113 series strains. This adds to the available information about substrate‐gene‐performance, and provides new information to enable engineering to regulate the colonization of Lactiplantibacillus. © 2021 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

A microbial fuel cell (MFC) was constructed with CNTs, 0.02gMnO 2 /CNTs and 0.03gMnO 2 /CNTs modified graphite anode prepared by coating for enhancing copper wastewater treatment. The SEM, XRD and FTIR results showed that MnO 2 /CNTs and CNTs were successfully attached to the graphite electrode, indicating that the electrode was modified successfully. The surface wettability test showed that the decrease of the contact angle of the modified anode led to the increase of hydrophilicity, which was more conducive to microbial adhesion. The surface contact angle of CNTs modified electrode was the smallest, which was 11.17°. The maximum output voltage, power density and copper removal rate of 0.03gMnO 2 /CNTs modified anode MFC were 0.67 V, 1044.21 mW/m2 and 98.93% respectively, which were 52.3%, 466.3% and 50.5% higher than those of unmodified anode. XPS results showed that the reduction products were Cu 2 O and Cu. Meanwhile，high throughput sequencing showed that CNTs and MnO 2 could improve the richness and diversity of microbial community. MnO 2 /CNTs modified-anode accelerated the enrichment of electro-active bacteria such as Proteobacteria , Firmicutes and Bacteroidetes. [ABSTRACT FROM AUTHOR]

Although the adhesion of bacteria on surfaces is a widely studied process, to date, most of the works focus on a single species of microorganisms and are aimed at evaluating the antimicrobial properties of biomaterials. Here, we describe how a complex microbial community, i.e., the human gut microbiota, adheres to a surface to form stable biofilms. Two electrospun structures made of natural, i.e., gelatin, and synthetic, i.e., polycaprolactone, polymers were used to study their ability to both promote the adhesion of the human gut microbiota and support microbial growth in vitro. Due to the different wettabilities of the two surfaces, a mucin coating was also added to the structures to decouple the effect of bulk and surface properties on microbial adhesion. The developed biofilm was quantified and monitored using live/dead imaging and scanning electron microscopy. The results indicated that the electrospun gelatin structure without the mucin coating was the optimal choice for developing a 3D in vitro model of the human gut microbiota. [ABSTRACT FROM AUTHOR]

Background/purpose: Orthodontic wax materials are available on the dental market and are given by orthodontists due to pain, sores and irritation caused by treatment. The aim of the study was to compare biofilm formation and microbial adhesion at different time points on different protective materials used against orthodontic wounds in vitro. Materials and methods: Microbial adhesion and biofilm formation were evaluated against Streptococcus mutans ATCC 25175 and Lactobacillus acidophilus ATCC 4356 standard strains on orthodontic wax materials at the 0, 24th, 48th, 72nd, 96th and 120th hour. The Kruskal Wallis test and Bonferroni test were used for statistical evaluations. Statistical significance was set at p

Introduction. The adhesion of microorganisms and the formation of dental plaque on acrylic denture surfaces are the primary causes of several oral diseases. To form the polymer, PMMA pre polymerized fine particles are mixed with a liquid monomer resulting in chains of polymer. PMMA provisional materials are susceptible to bacterial adhesion and colonization when compared to materials used for final restorations due to the increased surface roughness

Candida albicans-related bloodstream infections are often associated with infected central venous catheters (CVC) triggered by microbial adhesion and biofilm formation. We utilized single-cell force spectroscopy (SCFS) and flow chamber models to investigate the adhesion behavior of C. albicans yeast cells and germinated cells to naïve and human blood plasma (HBP)-coated CVC tubing. Germinated cells demonstrated up to 56.8-fold increased adhesion forces to CVC surfaces when compared to yeast cells. Coating of CVCs with HBP significantly increased the adhesion of 60-min germinated cells but not of yeast cells and 30-min germinated cells. Under flow conditions comparable to those in major human veins, germinated cells displayed a flow directional-orientated adhesion pattern to HBP-coated CVC material, suggesting the germ tip to serve as the major adhesive region. None of the above-reported phenotypes were observed with germinated cells of an als3Δ deletion mutant, which displayed similar adhesion forces to CVC surfaces as the isogenic yeast cells. Germinated cells of the als3Δ mutant also lacked a clear flow directional-orientated adhesion pattern on HBP-coated CVC material, indicating a central role for Als3 in the adhesion of germinated C. albicans cells to blood exposed CVC surfaces. In the common model of C. albicans, biofilm formation is thought to be mediated primarily by yeast cells, followed by surface-triggered the formation of hyphae. We suggest an extension of this model in which C. albicans germ tubes promote the initial adhesion to blood-exposed implanted medical devices via the germ tube-associated adhesion protein Als3.

The ability to adhere via colonization factors to specific receptors located on the intestinal mucosa is a key virulence factor in enterotoxigenic Escherichia coli (ETEC) pathogenesis. Here, the potential glycosphingolipid receptors of the novel human ETEC colonization factor CS30 were examined by binding of CS30-expressing bacteria to glycosphingolipids on thin-layer chromatograms. We thereby found a highly specific binding of CS30-expressing bacteria to a fast-migrating acid glycosphingolipid of human and porcine small intestine, while no binding was obtained with a mutant ETEC strain unable to express CS30 fimbriae. The CS30 binding glycosphingolipid from human small intestine was isolated and characterized by mass spectrometry as sulfatide (SO3-3Galβ1Cer). Comparative binding studies using sulfatides with different ceramide compositions gave a preferential binding of CS30 to sulfatide with d18:1-h24:0 ceramide. This ceramide species of sulfatide was also isolated from human small intestine and characterized by mass spectrometry and antibody binding. These studies implicate sulfatide as candidate receptor for mediating attachment of CS30-fimbriated ETEC to human and porcine small intestinal cells. Our findings may be a basis for designing receptor saccharide analogues for inhibition of the intestinal adhesion of CS30-expressing E. coli.

Introduction: Oral cavity is a natural habitat of bacteria which proliferates when an orthodontic appliance is placed which leads to enamel demineralisation or white spot lesions. In order to reduce the bacterial proliferation, the surface coating of brackets using nano particles came into existence. Aim: The aim of this systematic review is to assess the different surface modifications using nano coating materials and evaluate the antibacterial properties of these nano coated orthodontic brackets. Materials and Methods: A systematic review was conducted in September 2021, analysing the microbial adhesion and antibacterial properties of orthodontic brackets after application of nano-coating against uncoated brackets was conducted from the available electronic database during January 2000 to June 2021, which included PubMed, Embase, Google Scholar. Because of the less number of in-vivo studies, in-vitro studies were also included. An analysis on the microbial adhesion and antibacterial effects of various orthodontic brackets was done. The results were tabulated after performing risk of bias assessment for each study. Results: Based on the inclusion and exclusion criteria, 13 studies were included in the study. Risk of bias was medium for majority of the selected studies. As per the previous literature, bacterial adherence of Streptococcus mutans, Streptococcus sobrinus, Aggregatibacter actinomycetemcomitans, Lactobacillus acidophilus, Actinomyces viscous and Candida albicans was reported lower in groups of brackets coated with silver nano particles than that in the groups of brackets without the addition of silver nano particles. The corrosion level on the silver or silver platinum (Ag-Pt)-coated specimens was lower than that on the non coated specimens. Conclusion: The stainless-steel orthodontic brackets coated with various nano coating materials like silver, silver-platinum, titanium, Zinc Oxide (ZnO) and Copper Oxide (CuO) exhibited adequate antibacterial effect. This shows that in orthodontic patients, especially the one susceptible to caries, the amount of plaque accumulation is significantly reduced when nano-coated orthodontic brackets are used. They reduce the microbial colony count and prevent enamel demineralisation and white spot lesions. Further clinical trials must be carried out on a large scale to confirm the results. [ABSTRACT FROM AUTHOR]

Bacterial contamination is among the major issues that occur in surgical instruments and biomedical implants. Bacterial adhesion to surgical instruments and bioimplants form a biofilm that causes microbial infection. Various surface texturing methods are being developed to change the surface properties for reducing the adhesion and colonization of bacteria. Hierarchical structure with dual-scale (micro-nano) surface roughness over materials counters bacterial growth and its spread. In this investigation, WEDM (wire electrical discharge machining) process is adopted to generate hydrophobic surface over Ti6Al4V due to its wide application in the biomedical field. The objective of this work is to evaluate the wettability and antibacterial property of fabricated curved microarray structure over Ti6Al4V. The obtained result shows that the hierarchical structure with dual-scale surface roughness increases the hydrophobicity as compared to non-hierarchical structure. E-coli was selected for bacterial adhesion investigation because this bacterial strain is very common on surgical instruments and bioimplants. The antibacterial investigation reported that colony-forming unit (CFU) of E-coli reduced from 1200 CFU for as received surface to 96 CFU for curved microarray structure. [ABSTRACT FROM AUTHOR]

Development and further use of biodegradable polymeric materials requires prior assessment the degree of their biodegradation. There are a large number of methods developed taking into account the specifics of the destruction of polymeric materials. The purpose of this review is to systematize scientific and technical information regarding methods for assessing the biodegradation of polymeric materials. Laboratory methods of researches, including the following: influence of abiotic factors (temperature, moisture, UV irradiation), impact of microorganisms (fungi, bacteria, yeast), respiratory methods (Sturm, Zahn-Wellness, etc.), conditions of composting, enzyme analysis methods, ecotoxicity tests are given. Test methods in both aqueous and solid media are also presented. The parameters of biodegradability, which determine the degree of destruction (mass, strain strength, molecular weight distribution, temperature characteristics, macro-and microstructure of samples, etc.) or the composition and properties of the biological system in which biodegradation takes place (acidity, respiratory activity, chemical and microbiological composition of soil or other biological environment, etc.) are considered as well. Advantages of laboratory methods for studying the biodegradation of polymeric materials could be realized in the given directions: varying of the experimental conditions (temperature, humidity, UV and IR radiation, the presence of aggressive media, etc.), biochemical compositions of the environment; study of the ability of individual strains of microorganisms to dispose of polymer composites and targeted selection of the most active microbial associations (in particular, for the manufacture of special biocomposts); utilize of simple and fast methodical approaches and modern devices for evaluation experiments. However, laboratory methods do not always allow modeling a set of endogenous and exogenous factors that define the process of biodegradation in the natural environment. Therefore, this review also considers methods for assessing biodegradation in the environment. So, the essence of the test regarding the samples' burial in the ground is given. International standards governing methods for assessing the biodegradability of organic substances and polymeric materials are summarized. Applying different test methods, one can evaluate the whole process of biodegradation of polymeric materials, consisting of several stages, which occur regardless the type of microorganisms and accompanying abiotic factors, and can be represented as follows: adhesion → colonization → biodeterioration → biofragmentation → assimilation → mineralization. Thus, the adhesion and colonization of microorganisms can be estimated by visual, bioindicator and spectral methods. Abiotic degradation and biodeterioration are associated with physical tests (e.g., thermal and physico-mechanical). Biofragmentation is detected by identifying fragments of lower molecular weight (i.e. by chromatographic methods). In turn, assimilation is assessed by the amount of metabolites produced using, for example, respirometric methods or involving analysis of microbial biomass (e.g., macroscopic and microscopic observations). The most productive should be considered a comprehensive approach to the study of biodegradation of polymers. To determine the reliable kinetic parameters and link the mechanism of this process, it is necessary to carry out a comparative analysis of the results of physical, chemical, microbiological experiments, which are carried out in both laboratory and natural conditions. [ABSTRACT FROM AUTHOR]

This review illustrates the relationships between additives in the diets of ruminants and the consequence for ruminant nutrition. Feed additives are used to improve animal performance and/or the quality of the products. There are several categories of additives available for ruminant nutrition, with emphasis on antibiotics, prebiotics, probiotics, plant extracts, and exogenous enzymes. Antibiotics, essential oils, and chitosan act by selecting sensitive bacteria, consequently modulating the ruminal fermentation pattern. Prebiotics favor microbial growth, providing greater digestion and the production of volatile fatty acids. Probiotics are living microorganisms that improve the ruminal environment, promoting microbial growth and resulting in increased digestion and the production of volatile fatty acids. Exogenous enzymes act synergistically with the enzymes secreted by the ruminal microorganisms, besides favoring microbial adhesion and colonization and facilitating feed degradation. Tannins, whether altering the fermentation standard and/or modifying the ruminal microbiota population, are effective in improving animal performance. However, the effects of additives on the quality of the products are linked to diet quality. [ABSTRACT FROM AUTHOR]

• The growth inhibitory effect of the anti- killed whole cell IgY was higher than anti-pilQ-pilA IgY. • Intravenous administration of specific IgY was non protective against Pseudomonas aeruginosa sepsis in a rabbit model. • No bacteria were found in the spleen and liver samples from infected rabbit. Pseudomonas aeruginosa sepsis is associated with unacceptably high mortality and, for many of those who survive, long-term morbidity. The aims of this study were to production of IgY against chimeric protein pilQ-pilA-DSL region and killed- whole cell Pseudomonas aeruginosa O1 (PAO1) strain and their efficacy for immunoprophylaxis of sepsis caused by P. aeruginosa in a rabbit model. Specific IgY was obtained by immunization of hens. The purity of IgY was determined by SDS-PAGE analysis. The effect of IgY on growth and hydrophobicity of P. aeruginosa were performed through time-kill assay and microbial adhesion to hydrocarbons test (MATH), respectively. The efficacy of specific IgYs was examined against P. aeruginosa sepsis in a rabbit model. The rabbits were monitored for 72 h to record physiological characters and survival. Hematologic factors, C-reactive protein, pro-inflammatory cytokines, and bacterial count from blood and solid organs were measured, periodically. We found that the growth inhibitory effect of the anti- killed whole cell IgY was higher than anti-pilQ-pilA IgY (P < 0.001). The hydrophobicity effect of PAO1 increased when bacteria were opsonized by anti- killed whole cell IgY while the hydrophobicity activity was decreased following incubation of PAO1 with anti-pilQ-pilA IgY in a broth medium (P < 0.001). Following intravenous (IV) administration of produced IgYs, no significant difference was observed in the survival, decrease in inflammatory mediators and clinical symptoms between the groups 48h post infection (P > 0.05). Moreover, no considerable decrease was observed in the bacterial load of blood, lungs and kidneys in rabbits treated with specific IgYs and control groups (P > 0.05). No bacteria were found in the spleen and liver samples from infected rabbits. Although produced IgYs had a good immunoreactivity, IV immunization of IgYs was not protective against P. aeruginosa sepsis in the rabbit model. Further studies are needed to assess the immune response and decreasing mortality rate using the rabbit sepsis model. [ABSTRACT FROM AUTHOR]

In microbial fuel cell (MFC), the anode is the carrier of microbial attachment and growth, and its material and surface structure play a vital role in MFC electricity generation. Therefore, anode surface optimization is an effective way to improve MFC performance. Although the power generation of bacteria has been confirmed and studied as early as the beginning of the 20th century, up to now, MFC still has the extremely challenging problem of low current and low power output in practical application. To improve the performance of MFC, several strategies have been applied to enhance the bacterial extracellular electron transfer. One promising technology is the genetic engineering approach, and some outstanding research results have been obtained. Another effective strategy is to design and fabricate a high-performance electrode because anode material is the essential factor affecting MFC performance, which provides surface active sites for microbial adhesion, reproduction and interfacial electron transfer. At present, the MFC anodes mainly include carbon-based electrodes and a variety of metal electrodes, but untreated anodes have always been unable to overcome the obstacle of low power output. Anode modification, a common and effective method, is employed for improving the power output of MFC. For this reason, this review is primarily focused on the applications of various anode materials and its nanoscale modification in the field of MFC, including the influence of different anode materials on the power output of MFC, and analyzes the reasons why anode modification enhances output performance. Furthermore, the influence of anode research on the practical application of MFC in the future is prospected. [ABSTRACT FROM AUTHOR]

Introduction. Microbial surfactants can affect the degree of microorganism's adhesion to different surfaces and lead to biodegradation of the already formed biofilms. They are also non-toxic to the environment. These properties allow to use the microbial surfactants in medicine and food industry. Material and methods. Surfactants were obtained by cultivation of the Rhodococcus erythropolis IMV Ac-5017 on waste from biodiesel production, used sunflower oil after frying meat, potatoes, onions, and cheese. The surfactants were extracted from the supernatant of cultural liquid by a Folch mixture. The anti-adhesive activity and the degree of destruction of biofilms were determined by spectrophotometric method. Results and discussion. It was found that surfactants obtained by cultivation of R. erythropolis IMV Ac-5017 on waste mixed sunflower oil reduce the adhesion of yeast Candida albicans D-6, Candida utilis BVS-65, Candida tropicalis PE-2 and bacterial strains Escherichia coli IEM-1, Bacillus subtilis BT-2, Pseudomonas sp. MI-2 to abiotic surfaces (tiles, steel and glass) by 51-73% and 57-86%, respectively. The effectiveness of the anti-adhesive activity of surfactants, obtained on waste from biodiesel production as a substrate against the studied yeast and bacterial cultures was lower (44-77%). The ability of surfactants to destroy of bacterial biofilms by 44-73% was achieved at low concentrations of surfactants (8-15 µg/ml) synthesized on different waste oil. Surfactants were equally effective in destroying biofilms (72-80%) of Candida genus and their activities were not depended on the nature of carbon source in the culture medium of R. erythropolis IMV Ac-5017. Conclusion. The obtained results show the possibility of using surfactants of R. erythropolis IMV Ac-5017, gained on industrial waste, as effective anti-adhesive and antibiofilm agents. [ABSTRACT FROM AUTHOR]

Endometrial injury can cause intrauterine adhesions (IUA) and induce the formation of endometrial fibrosis, leading to infertility and miscarriage. At present, there is no effective treatment method for severe IUA and uterine basal injury with adhesion area larger than one-third of the uterus. In this study, we prepared FGF1 silk sericin hydrogel material (FGF1-SS hydrogel) to treat endometrial injury and prevent endometrial fibrosis. Compared with the silk sericin hydrogel material (WT-SS hydrogel), FGF1-SS hydrogel significantly promotes the cell migration and infiltration ability of endometrial stromal cells (ESCs). More importantly, FGF1-SS hydrogel can release FGF1 stably for a long time and inhibit the ESCs injury model forms fibrosis through the TGF-β/Smad pathway. In the IUA rat model, FGF1-SS hydrogel treatment effectively restored the number of uterine glands and uterine wall thickness in rats, with a fertility rate of 65.1% ± 6.4%. The results show that FGF1-SS hydrogel is expected to be a candidate to prevent IUA. [ABSTRACT FROM AUTHOR]

Developing an effective and efficient recycling process for marine debris (MD) is one of the most urgent issues to maintain environmental sustainability on Earth. However, restricted storage capacities and secondary pollution (e.g., microbial adhesion, putrefaction) limit the proper MD recycling. Here, we proposed a complete eco-friendly low-temperature MD pulverizing system that utilizes excessive liquefied natural gas (LNG) cold energy (LCE) in an LNG propulsion ship to improve the efficiency and effectiveness of MD recycling. The prototype design of the low-temperature pulverization (LTP) system showed that consumable refrigerant (liquid nitrogen) up to 2831 kg per hour could be substituted. Furthermore, with a 20% ship output, 1250 kg of MD could be treated with 363 kg of additional refrigerant. In addition, LTP systems utilizing LCE could increase the storage capacity by more than 10 times compared to bulk MD while minimizing the required energy consumption. To determine the feasibility of LTP for MD recycling, four types of plastics obtained from actual MD from a coastal area in Busan, Korea were classified and tested. [ABSTRACT FROM AUTHOR]

Ti6Al4V alloys are the primary materials used for clinical bone regeneration and restoration; however, they are substantially susceptible to biomaterial-related infections. Therefore, in the present work, we applied a controllable and stable oxidative nanopatterning strategy by applying H3PO4, a weaker dissociating acid, as a substitute for H2SO4 in the classical piranha reaction. The results suggest that our method acted as a concomitant platform to develop reproducible diameter-controlled TiO2 nanopores (NPs). Interestingly, our procedure illustrated stable temperature reactions without exothermic responses since the addition of mixture preparation to the nanopatterning reactions. The reactions were carried out for 30 min (NP14), 1 h (NP7), and 2 h (NP36), suggesting the formation of a thin nanopore layer as observed by Raman spectroscopy. Moreover, the antimicrobial activity revealed that NP7 could disrupt active microbial colonization for 2 h and 6 h. The phenotype configuration strikingly showed that NP7 does not alter the cell morphology, thus proposing a disruptive adhesion pathway instead of cellular lysis. Furthermore, preliminary assays suggested an early promoted osteoblasts viability in comparison to the control material. Our work opens a new path for the rationale design of nanobiomaterials with "intelligent surfaces" capable of decreasing microbial adhesion, increasing osteoblast viability, and being scalable for industrial transfer. [ABSTRACT FROM AUTHOR]

In the review there are considered the recent data on the perspectives of the use of polysaccharides (PS) from marine hydrobionts for inhibition of formation of bacterial biofilms, which play a significant role in the onset and process of different infections, as well as for design of antiadhesive coatings on medical produce. Particular attention is paid to antiadhesive properties of natural PS from marine microorganisms, algae and invertebrate animals, which prevent formation of biofilms. Antibiofilm PS possess such positive characteristics, as biocompatibility and biodegradability, that is of great interest for medical and industrial applications. The possibility of simultaneous use of complexes of compounds of different chemical nature and mechanisms of action in infectious diseases, involving biofilm formation is of special interest. It is believed that biologically active substances from marine hydrobionts could serve as the basis for development of new antibiofilm drugs, including complex ones.

Introduction: Oral cavity is a natural habitat of bacteria which proliferates when an orthodontic appliance is placed which leads to enamel demineralisation or white spot lesions. In order to reduce the bacterial proliferation, the surface coating of brackets using nano particles came into existence. Aim: To assess the different surface modifications using nano coating materials and to evaluate the antibacterial properties of these nano coated orthodontic brackets. Materials and Methods: A systematic review was conducte in September 2021, analysing the microbial adhesion and antibacterial properties of orthodontic brackets after application of nano coating against uncoated brackets was conducted from the available electronic database during January 2000 to June 2021, which included PubMed, Embase, Google Scholar and Medical Literature Analysis and Retrieval System Online (MEDLINE). Due to less number of in-vivo studies, in-vitro studies were also included. An analysis on the microbial adhesion and antibacterial effects of various orthodontic brackets was done. The results were tabulated after performing risk of bias assessment for each study. Results: Based on the inclusion and exclusion criteria, 13 studies were included in the study. Risk of bias was medium for majority of the selected studies. As per the previous literature, bacterial adherence of Streptococcus mutans, Streptococcus sobrinus, Aggregatibacter actinomycetemcomitans, Lactobacillus acidophilus, Actinomyces viscous and Candida albicans was reported lower in groups of brackets coated with silver nano particles than that in the groups of brackets without the addition of silver nano particles. The corrosion level on the silver or silver platinum (Ag-Pt) coated specimens was lower than that on the non coated specimens. Conclusion: The stainless-steel orthodontic brackets coated with various nano coating materials like silver, silver-platinum, titanium, Zinc Oxide (ZnO) and Copper Oxide (CuO) exhibited adequate antibacterial effect. This shows that in orthodontic patients, especially the one susceptible to caries, the amount of plaque accumulation is significantly reduced when nano-coated orthodontic brackets are used. They reduce the microbial colony count, prevent enamel demineralisation and white spot lesions. Further clinical trials must be carried out on a large scale to confirm the results.

The mechanism behind how flavin mononucleotide (FMN)-producing bacteria attach to a host intestine remains unclear. In order to address this issue, this study isolated the Gram-positive bacteria Lactobacillus plantarum from Mongolian fermented Airag, named L. plantarum MA. These bacteria were further employed as the model microbes, and their electrogenic properties were first identified by their significant expression of type II NADH-quinone oxidoreductase. This study also demonstrated that the electrical activity of L. plantarum MA can be conducted through flavin mononucleotide (FMN)-based extracellular electron transfer, which is highly dependent on the presence of a carbon source in the medium. Our data show that approximately 15 µM of FMN, one of the key electron donors for the generation of electricity, can be produced from L. plantarum MA, as they were cultured in the presence of lactulose for 24 h. We further demonstrated that the electrical activity of L. plantarum MA can promote microbial adhesion and can thus enhance the colonization effectiveness of Caco-2 cells and mouse cecum. Such enhanced adhesiveness was attributed to the increased expression of type I collagens in the intestinal epithelium after treatment with L. plantarum MA. This study reveals the mechanism behind the electrogenic activity of L. plantarum MA and shows how the bacteria utilize electricity to modulate the protein expression of gut tissue for an enhanced adhesion process.

Bacterial keratitis is a risk associated with the use of contact lenses for cosmetic purposes or vision correction. In this in vitro experimental study, we examined the ability of the ocular pathogen Serratia marcescens to adhere to monthly or biweekly replacement contact lenses. We performed quantitative adhesion assays to evaluate the adherence of S. marcescens to seven contact lens materials: comfilcon A, senofilcon A, omafilcon B, fanfilcon A, balafilcon A, senofilcon C, and lehfilcon A. Lehfilcon A is a newly marketed silicon hydrogel contact lens with a surface modification of poly-(2-methacryloyloxyethyl phosphorylcholine) (PMPC). PMPC has previously been demonstrated to be an effective anti-biofouling treatment for numerous surfaces. We observed low S. marcescens adherence to lehfilcon A compared to other materials. We demonstrate the use of the fluorescent dye 5(6)-Carboxytetramethylrhodamine succinimidyl ester to covalently stain live cells prior to material adhesion studies.

The physical essence of the formation and influence of bacteria on the surface of technological equipment in the dairy industry is considered as an essential factor leading to contamination of dairy products and is a major hygienic problem. The ability of microorganisms on the surfaces of technological equipment to form biofilm forms and requirements for steel grade, relief, and its roughness were analysed. The effect of surface roughness on promoting or preventing adhesion and reproduction of biofilm forms of bacteria, which reduce the efficiency of sanitary processing of dairy equipment and thereby increase the microbial contamination of dairy products with shortened shelf life, is substantiated. Research about the process of bacterial adhesion to the surface of metals with different roughness depending on the size and shape is presented. It is found that on the surface of stainless steel with roughness 2.687 ±0.014 micron film formation process in Escherichia coli and Staphylococcus aureus are similar from 3 to 24 hours and does not depend on the size of the bacteria, and accordingly allows us to argue that rod-shaped and coccid bacteria attach freely in the hollows of the roughness are the beginning of the process of the first stage of biofilm formation. It is found that on the surface of stainless steel with roughness 0.95 ±0.092 micron film formation process in S. aureus is more intense than in E. coli. Thus, within 3 hours of incubation, the density of biofilms formed S. aureus was 1.2 times bigger than biofilms E. coli, by the next 15 hours of incubation formed biofilms S. aureus were, on average, 1.3 times denser. It is established that S. aureus due to its spherical shape is able to fit in the hollows of the roughness 0.95 ±0.092 μm and faster to adhere to the surface at the same time. E. coli, due to its rod-like shape, with such surface roughness, can adhere to the cavities only over its entire length. It is proved that by surface roughness 0.63 ±0.087 μm film intensity S. aureus was, on average, 1.4 times faster than E. coli, for roughness 0.16 ±0.018 micron film formation process took place equally for S. aureus and E. coli, but biofilms were lower in density than those formed on roughness 0.63 ±0.087 micron. Studies suggest that the use of equipment in the dairy industry with a roughness of less than 0.5 microns will reduce the attachment of microorganisms to the surface and reduce the contamination of dairy products.

Stainless steel crowns (SSC) have long been the standard choice due to their durability, ease of use, and cost-effectiveness. Other esthetic crowns, known for their superior esthetic properties and biocompatibility, have emerged as a popular option in recent years. A comprehensive literature search was conducted across multiple databases, including PubMed, Scopus, and Cochrane Library, up to June 2024. The population under study was primary teeth, with the intervention being the application of aesthetic crowns. These were compared against SSC, with the primary outcome being the level of microbial adhesion on the crowns in primary teeth. Data extraction and quality assessment were performed independently by two reviewers. Meta-analyses were conducted using random-effects models to estimate pooled differences in microbial adhesion levels. A total of five studies were included in the review. The meta-analysis revealed a statistically significant difference in microbial adhesion between esthetic and SSC, with esthetic crowns showing lower levels of bacterial colonization. Specifically, the mean difference in colony-forming units (CFU). Esthetic crowns exhibit significantly lower microbial adhesion compared to SSC in pediatric patients, suggesting a potential advantage in reducing the risk of secondary caries and other microbial-related complications. However, further long-term clinical studies are warranted to confirm these results and assess their clinical implications., Competing Interests: Conflicts of interest: In compliance with the ICMJE uniform disclosure form, all authors declare the following: Payment/services info: All authors have declared that no financial support was received from any organization for the submitted work. Financial relationships: All authors have declared that they have no financial relationships at present or within the previous three years with any organizations that might have an interest in the submitted work. Other relationships: All authors have declared that there are no other relationships or activities that could appear to have influenced the submitted work., (Copyright © 2024, K L S et al.)

The rapid spread of microorganisms such as bacteria, fungi, and viruses can be extremely detrimental and can lead to seasonal epidemics or even pandemic situations. In addition, these microorganisms may bring about fouling of food and essential materials resulting in substantial economic losses. Typically, the microorganisms get transmitted by their attachment and growth on various household and high contact surfaces such as doors, switches, currency. To prevent the rapid spread of microorganisms, it is essential to understand the interaction between various microbes and surfaces which result in their attachment and growth. Such understanding is crucial in the development of antimicrobial surfaces. Here, we have reviewed different approaches to make antimicrobial surfaces and correlated surface properties with antimicrobial activities. This review concentrates on physical and chemical modification of the surfaces to modulate wettability, surface topography, and surface charge to inhibit microbial adhesion, growth, and proliferation. Based on these aspects, antimicrobial surfaces are classified into patterned surfaces, functionalized surfaces, superwettable surfaces, and smart surfaces. We have critically discussed the important findings from systems of developing antimicrobial surfaces along with the limitations of the current research and the gap that needs to be bridged before these approaches are put into practice. [ABSTRACT FROM AUTHOR]

Microbial adhesion constitutes the transition of microorganisms from a planktonic mode to a static one. It promotes the formation of biofilm which is responsible for spoilage, foodborne diseases, and corrosion in the food processing industry. In this study, the adhesive potential of fourteen meat-borne bacterial isolates belonging to seven different genera was investigated. All strains were found able to colonize polystyrene surfaces with different levels of firmness. Significant variations were determined in assays of bacterial hydrophobicity and motility. Among the 14 strains, Pseudomonas fragi, Aeromonas salmonicida II, Serratia liquefaciens, Citrobacter braakii, Pseudomonas putida, and Aeromonas veronii had a strong hydrophobic force, while the isolates of Lactobacillus genus showed the most hydrophilic property. In terms of motility, Citrobacter braakii and Escherichia coli exhibited exceptional swarming and swimming abilities, whilst conservatively weak performances were observed in the Lactobacillus strains. Furthermore, the majority of the isolates were predominantly electron donors and weak electron acceptors. Overall, a high level of correlation was observed between biofilm-forming ability with cell surface hydrophobicity and Lewis acid–base properties, whereas the contribution of motility in bacterial adhesion could not be confirmed. Research on the adhesive performance of foodborne bacteria is potentially conducive to developing novel control strategies, such as food processing equipment with specific surfaces, not facilitating attachment. [ABSTRACT FROM AUTHOR]

• Bacterial adhesion to the surface of dental materials play a significant role in infections. • The factors that govern microbial attachment involves different types of physical-chemical interactions and biological processes. • Studying bacterial adhesion makes it possible to understand the mechanisms involved in attachment and helps in the search for technologies that promote antibacterial surfaces. Bacterial attachment to biomaterials is of great interest to the medical and dental field due to its impact on dental implants, dental prostheses, and others, leading to the need to introduce methods for biofilm control and mitigation of infections. Biofilm adhesion is a multifactorial process and involves characteristics relevant to the bacterial cell as well as biological, chemical, and physical properties relative to the surface of biomaterials. Bacteria encountered different environmental conditions during their growth and developed interspecies communication strategies, as well as various mechanisms to detect the environment and facilitate survival, such as chemical sensors or physical detection mechanisms. However, the factors that govern microbial attachment to surfaces are not yet fully understood. In order to understand how bacteria interact with surfaces, as well as to characterize the physical-chemical properties of bacteria adhesins, and to determine their interrelation with the adhesion to the substrate, in recent years new techniques of atomic force microscopy (AFM) have been developed and helped by providing quantitative results. Thus, the purpose of this review is to gather current studies about the factors that regulate microbial adhesion to surfaces in order to offer a guide to studies to obtain technologies that provide an antimicrobial surface. [ABSTRACT FROM AUTHOR]

Microbial adhesion to host cells represents the initial step in the infection process. Several methods have been explored to inhibit microbial adhesion including the use of glycopolymers based on mannose, galactose, sialic acid and glucose. These sugar receptors are, however, abundant in the body, and are not unique to bacteria. Trehalose, in contrast, is a unique disaccharide that is widely expressed by microbes. This carbohydrate has not yet been explored as an anti‐adhesive agent. Herein, gold nanoparticles (AuNPs) coated with trehalose‐based polymers were prepared and compared to glucose‐functionalized AuNPs and examined for their ability to prevent binding to endothelial cells. Acting as anti‐adhesive agents, trehalose‐functionalized NPs decreased the binding of S. aureus to HUVECs, while outperforming the control NPs. Microscopy revealed that trehalose‐coated NPs bound strongly to S. aureus compared to the controls. In conclusion, nanoparticles based on trehalose could be a non‐toxic alternative to inhibit S. aureus infection. [ABSTRACT FROM AUTHOR]

Microbial adhesion to surfaces is thought to involve physicochemical interactions between the substrate and microbial cells. Understanding the physicochemical aspects involved in the adhesion phenomenon, as a critical step in biofilm formation, is essential to finding ways to prevent their formation and control biocontamination risks. The aim of this study was to investigate the relation between the adhesion behavior of 12 Escherichia coli strains isolated from food and their surface hydrophobicities using qualitative ( θ w ) and quantitative (ΔGiwi) approaches. The surface physicochemical properties of both bacterial cells and glass material were estimated through contact angle measurements. The adhesive behavior of E. coli strains on a glass surface was assessed. The results showed a good logarithmic relation between the percentage of the adhered cells and their surface hydrophobicity with the quantitative approach ΔGiwi; however, qualitative hydrophobicity ( θ w ) appeared to demonstrate no effect regarding adhesion behavior. This work lays the foundation for future studies and opens an important debate on the mechanisms underlying the adhesion behavior of E. coli strains by using the thermodynamic approach (ΔGiwi) as an important model of hydrophobicity that could explain and predict better bacterial adhesion ability. [ABSTRACT FROM AUTHOR]

Of note, I Enterococcus i sp. possess highly diverse glycobiological arrangements ( B Fig 1 b ) given their ability to build not only essential structural polysaccharides, such as peptidoglycan (PG), enterococcal polysaccharide antigen (EPA), and wall teichoic acids (WTAs), but also the capacity to synthesize capsule polysaccharides (CPs), lipoteichoic acids (LTAs), and other extracellular polysaccharides [[7]-[11]]. Sugarcoating it: Enterococcal polysaccharides as key modulators of host-pathogen interactions Among these polymers, PG creates a layer that protects cells from osmotic pressure, reinforces cell shape and size, and shelters cell envelope components, including other structural/nonstructural polysaccharides [[28]]. I faecalis i OG1RF biofilm formation [[32]], recent studies using the same parental strain demonstrated that mutants involved in either EPA backbone synthesis ( I epaI i and I epaQ i ) or EPA decoration ( I epaOX i ) decreased biofilm biomass only when grown in different settings with subinhibitory concentrations of antibiotics [[20], [22]]. Below, we summarize recent findings highlighting the critical role of polysaccharides in enterococcal biofilms: Cell and surface attachment Enterococcal glycopolymers, such as PG, LTAs, EPA, and other exopolysaccharides, contribute to the initiation of biofilm formation. [Extracted from the article]

Streptomyces are known for their ability to produce various secondary metabolites used in biotechnology, human medicine and agriculture. Understanding of surface properties is very interesting in the control of interfacial phenomena. The objective of this study was to investigate the effect of consistency and composition of growth medium on the physicochemical properties of the surface of Streptomyces strains. To achieve this objective, Six Streptomyces strains belonging to bioprocess and bio-interfaces laboratory are cultivated in two media Bennett (rich) and GBA (minimum). Both media are tested in solid (agar) and liquid (broth) mode. The wettability θw, electron donor character ˠ (-), electron acceptor character ˠ (+) and Surface free energy ΔGiwi are determined using contact angle measurements. On the two solid media Bennett and GBA, Streptomyces strains develop a hydrophobic surface (96.9° <θw<167.9°) with a weak electron donor character (0.3 mJm-2 < (ˠ (-)) <12.14 mJm-2) and a strong electron acceptor character (0.26 mJm-2 < ˠ (+) < 17.8 mJm-2) and a negative surface free energy ((- 11.8 mJm-2) < ΔGiwi < (-110 mJm-2)). Whereas on both Bennett and GBA liquid media, the surfaces of Streptomyces strains are generally hydrophilic (1.3° < θw < 9.33°) with a strong electron donor character (13.76 mJm-2 < ( ˠ (-)) < 70.06 mJm-2) and a positive surface free energy. By changing the composition of the culture medium, only a slight change in the degree of hydrophobicity and surface free energy of Streptomyces is observed. Regarding the effect of medium composition on the surface properties of Streptomyces, the degree of wettability and the values of surface free energy are no longer the same when the composition of the medium changes. These results could be applied in further studies interested in interfacial phenomena and microbial adhesion in biotechnological fields. [ABSTRACT FROM AUTHOR]

Purpose: The purpose of this study was to evaluate, in situ, the initial adhesion of microorganisms to as well as the surface roughness and chemical composition of ProBase Hot (Ivoclar Vivadent), a hard acrylic resin, and Vertex Soft (Vertex-Dental), an acrylic-based soft liner, used in removable dental prostheses. Materials and Methods: Equal sized disks of ProBase Hot and Vertex Soft were prepared and polished according to the recommended procedures for clinical use. Two disks of each material were mounted in individual oral splints and exposed for 4 hours o the oral cavities of 15 participants. The microbial adhesion to each material's surface was measured with the pour plate technique using rich and selective growth media. Statistical analysis was performed using the Student t test. Scanning electron microscopy and chemical composition analyses obtained through electron probe radiographic microanalysis of sample disks also were performed. Results: In comparison to ProBase Hot, Vertex Soft presented higher microbial adhesion, namely egarding total aerobes, anaerobes, streptococci, and mutans streptococci (P < .05). Also, Vertex Soft presented higher surface roughness. Differences in the chemical composition of the two materials also were found. Conclusions: The Vertex Soft iner has been found to be more susceptible to microbial adhesion than the acrylic esin ProBase Hot, probably due to its greater surface roughness. The application of Vertex Soft liner to a hard denture base may lead to a higher risk of oral and systemic nfections for patients, highlighting a greater need for plaque control, especially for more susceptible individuals. [ABSTRACT FROM AUTHOR]

High utilization of thermoplastic polymers with low degradation rates as packaging materials generates a large amount of waste. Therefore, it should be replaced by natural polymers that can be degraded by microorganisms. In this paper, chitosan (CTS)/tannic acid (TA) materials in the weight ratios of 80CTS/20TA and 50CTS/50TA were prepared as potential packaging materials. The results showed that these materials were similarly degraded in soil and compost. However, in comparison to 50CTS/50TA, 80CTS/20TA was slightly better degraded in soil. After 14 days of biodegradation, the chemical structure of materials was changed resulting from adhesion of the microorganisms. The smallest changes were observed on 80CTS/20TA film. Bacterial species were collected and identified from materials after the degradation process. Microorganisms with the highest hydrolytic activity were chosen for the degradation study. Biodegradation and hydrolytic activity were observed only in a few strains, which indicate difficulties in material degradation. Soil bacteria degraded the films better than bacteria isolated from the compost. This study showed also that consortia of bacteria added to soil and compost had a positive effect on the biodegradation of the tested materials and increased the biodegradation of these materials in the studied environments. • The degradation rate of CTS/TA materials in soil and compost was checked. • CTS/TA materials were poorly degraded in soil and compost. • Selection of bacteria for inoculum is important for CTS/TA film acid biodegradation. • CTS/TA based films may be considered as active food packaging materials. [ABSTRACT FROM AUTHOR]

Objective(s): Catheters are one of the factors for complicated urinary tract infections. Uropathogenic bacteria can attach to the catheter via cell surface hydrophobicity (CSH), form biofilms, and remain in urinary tract. The study was evaluated phenotypic and genotypic characteristics of fimbriae in Klebsiella pneumoniae and uropathogenic Escherichia coli (UPEC) isolates from patients with catheterassociated urinary tract infections (CAUTIs) and their association with biofilm formation. Materials and Methods: Urine specimens were collected through catheters in patients with CAUTIs. Sixty bacterial isolates were identified by biochemical tests. For determination of biofilm formation a tissue culture plate was used. Microbial adhesion to hydrocarbons (MATH) was conducted for CSH determination. The mannose-sensitive haemagglutination (MSHA) and mannose-resistant haemagglutination (MRHA) were determined for type 1 and type 3 fimbriae. Finally, the presence of genes encoding fimbriae was determined by PCR. Results: All isolates showed strong CSH, biofilm capacity and MRHA phenotype. The results showed that 20% of UPEC and 23% of K. pneumoniae isolates contained MSHA phenotypes. There was a significant association between biofilm formation and MSHA phenotype in UPEC isolates. The frequency of fimA (80%) and fimH (96.6%) in K. pneumoniae isolates was higher than UPEC isolates. Both types of bacterial isolates with MSHA phenotypes harbored the fimH gene. Conclusion: The phenotypic and genotypic characteristics of two bacterial species were highly similar. Also, the type of fimbriae affected bacterial biofilm formation through catheterization. It seems that fimH and mrk gene cluster subunits are suitable markers for identifying bacterial pathogenesis. [ABSTRACT FROM AUTHOR]

Aims: Researchers are focusing more on the isolation of new probiotic bacteria to increase varieties for the growing market demand. This study aimed to isolate lactic acid bacteria (LAB) strains from sugarcane waste materials and evaluate its characteristic. Methodology and results: In the present study, two strains of LAB (Isolates A and B) were isolated from sugarcane waste and investigated in vitro for their characteristics as potential probiotics. These isolates were evaluated on their characteristics based on four biochemical tests (acid tolerance, bile tolerance, microbial adhesion, and phenol resistance), with the commercial strain Lactobacillus isolated from Yakult® served as a positive control. Both isolated strains (>8 log10 CFU/mL) displayed higher survivability than control (>6 log10 CFU/mL) in simulated gastrointestinal conditions at pH 2.0 and pH 6.9 after 24 h. Furthermore, both isolated LABs were resistant to inhibitory substances which are 0.05-0.3% bile and 0.4% phenol. For bile tolerance, isolate A (OD 6.83) had a higher absorbance at 0.3% bile concentration as compared to isolate B (OD 2.20). However, isolate B (7.49 log10 CFU/mL) showed higher resistance towards 0.4% phenol than isolate A (7.11 log10 CFU/mL) after 24 h. Both isolate A and isolate B displayed low cell surface hydrophobicity, strong electron donor, and basic characteristic. Conclusion, significance and impact of study: Both isolates were able to survive under gastrointestinal stress conditions, implying their potential as probiotics. This study demonstrated that valuable products such as probiotic strain could be isolated from sugarcane wastes to use in food production or medical treatment. [ABSTRACT FROM AUTHOR]

Developing biofilm carriers is of great significance for efficient wastewater treatment. In this work, ferric citrate was used to modify inorganic basalt fiber (BF) biocarrier, thus improving its surface properties and the nitrogen removal in hybrid wastewater treatment system. The results showed that the iron element on modified basalt fiber (Fe-MBF) existed in the forms of ferric citrate, Fe(OH)3, Fe2O3, and FeO. The ferric deposition increased the surface roughness, hydrophilicity and reduced the electronegativity of BF. The water contact angle of BF and Fe-MBF was 117.46° and 64.85°, respectively. The surface zeta potential of BF was −17.64 mV, but shifted positively (−8.67 mV) after deposition modification. The microorganism adhesion tests showed that the attached biomass and extracellular polymeric substances (EPS) content on Fe-MBF biocarrier significantly increased and the attached bacteria had also high viability. The Fe-MBF biocarrier showed good nitrogen removal performance in the hybrid bioreactor, with total nitrogen removal efficiency up to 95.35±0.82%, increasing by about 16% compared to that with unmodified BF biocarrier. This work also provided a green modification strategy to enhance biofilm carrier in wastewater treatment. [ABSTRACT FROM AUTHOR]

Objectives. Soft denture liners provide a favorable environment for adhesion and colonization of microorganisms. This in vitro study aimed to examine the efficacy of different concentrations of copper oxide nanoparticles (CuO NPs) incorporation into soft denture liner on the biofilm formation of the microbial species. Methods. Field Emission Scanning Electron Microscopy (FESEM) images from NPs were recorded. Antifungal susceptibility testing of CuO NPs against five standard strains of Candida albicans (CBS 10261, 1905, 1912, 1949, 2730), Streptococcus mutans (ATCC35668), Streptococcus sobrinus (ATCC27607), and Streptococcus salivarius (ATCC9222) was performed by the broth microdilution method with the Clinical and Laboratory Standards Institute reference method. The biofilm inhibition percentages of CuO NPs on the soft denture liners were determined by XTT assay. Results. The characterization of CuO NPs by scanning electron microscope (SEM) analyses confirmed the synthesis of NPs with appropriate structure and size with a mean diameter of 18.3 ± 9.1 nm. The CuO NPs successfully inhibited the growth of the tested standard strains of C. albicans and Streptococcus spp. at concentrations ranging from 64 to 128 µg mL−1. Indeed, incorporation of CuO NPs at a concentration of 500 µg mL−1 into the soft denture liners exhibited a significant activity (75%) in inhibition of C. albicans. biofilm formation in a dose-dependent manner. The biofilm formation of C. albicans in the presence of CuO NPs was lower than Streptococcus spp. in comparison with the control group (p < 0.05). Conclusion. Incorporation of CuO NPs significantly decreased the colonization and plaque formation of the oral pathogens, especially C. albicans accumulation. These NPs may be useful as a promising agent for the antimicrobial management of soft denture liner materials. [ABSTRACT FROM AUTHOR]

It is necessary to enhance the barrier performance of cutoff walls in order to improve the contamination control level, especially for reconstruction or expansion of existing landfill sites. This paper presents a comprehensive laboratory investigation on the synergistic effects of microorganisms and fibers on the hydraulic conductivity of silty sand to evaluate the applicability to the field condition as an alterative barrier material. Inside the soil, the added carbon fibers not only provided good biocompatibility, but also formed spatial three-dimensional network between soil particles to improve the bacterial adhesion that eventually caused 2–3 orders of magnitude decrease in soil permeability. The resistance of the biofilm to extreme conditions was tested by permeation with solutions of different salinity and pH values, and by subjecting specimens to various hydraulic gradients and soil conditions. Despite the microbial growth inhibition occurred at these conditions, however, biofilm can largely remain intact and continue to reduce k, which due to the gradual adaptation of microorganisms to the extreme environment and the gradual recovery of their activity. Results of these tests demonstrate that biofilm treatment may be a feasible technology for creating waste containment barriers in soil. • Using biomass-fiber-soil mixture as an alternative barrier material has been attempted. • The distributed discrete fibers in soils effectively promotes microbial adhesion. • Microbial adaptability to extreme environments can still reduce hydraulic conductivity. [ABSTRACT FROM AUTHOR]