Antimicrobial resistance (AMR) is a critical global health threat, with projections estimating up to 10 million deaths annually by 2050. One of the strategies for developing bacterial AMR is the formation of microbial biofilms (BFs). Thus, enzymes capable of degrading BF exopolysaccharides represent potential tools for BF disruption. In this work, we characterize β-1,6-N-acetylglucosaminidase from Serratia marcescens (SmPgaB), a two-domain enzyme with covalently attached GH153 and CE4 modules. Small-angle scattering data demonstrate that SmPgaB is monomeric in solution. We also demonstrate that SmPgaB degrades Staphylococcus aureus biofilms with up to 92% efficiency and inhibits biofilm formation by over 95%. Furthermore, SmPgaB enhances the effectiveness of gentamicin, tetracycline, and chloramphenicol, reducing the viability of planktonic cells by approximately 50% when used in combination with these antibiotics. Confocal laser scanning microscopy confirmed considerable morphological changes in the biofilm post-treatment. These results showcase the potential of β-1,6-N-acetylglucosaminidases as adjunct therapies for BF-related infections, particularly when combined with conventional antibiotics.

To evaluate the antibacterial and antibiofilm activity of tea tree oil (TTO) against a multidrug-resistant (MDR) Pseudomonas aeruginosa isolate, used as a representative model of the primary pathogen associated with contact lens-related keratitis. TTO was tested for minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC), and time-kill kinetics against P. aeruginosa . Biofilm (BF) formation and eradication assays were conducted using crystal violet (CV) and MTT viability tests on biofilms grown on CL surfaces. Cytotoxicity was evaluated in vitro using murine cone photoreceptor cells (661W). TTO showed strong antibacterial activity against MDR P. aeruginosa , with MIC and MBC values of 3.5 and 7 mg/mL, respectively. It inhibited biofilm formation and eradicated mature biofilms on silicone hydrogel contact lenses, outperforming commercial multipurpose solutions ( P <0.05). Cytotoxicity assays in 661W cells revealed a narrow therapeutic window, as effective concentrations were close to cytotoxic levels. TTO shows strong antibacterial and antibiofilm activity against MDR P. aeruginosa , outperforming commercial solutions in biofilm reduction. Although the narrow margin between effective and cytotoxic concentrations limits direct ocular use, its incorporation into contact lens care solutions appears promising for safe and effective prevention of microbial keratitis.

To investigate the mechanisms of biofilm (BF) formation in Salmonella pullorum (SP), a strong BF-forming strain designated 1904D10 was selected. Differential proteomics based on tandem mass tag (TMT) labeling was performed to compare the whole bacterial proteome between planktonic and biofilm states. A total of 219 differentially expressed proteins were identified (96 up-regulated, 123 down-regulated in biofilm state). Key up-regulated proteins included those involved in the EnvZ/OmpR two-component system (TCS), LuxS/AI-2 quorum sensing (QS) system, and AcrAB-TolC efflux pump. An ompR deletion mutant was constructed using Red homologous recombination. Deletion of ompR significantly reduced biofilm formation and significantly increased susceptibility to all tested antibiotics. Electrophoretic mobility shift assay (EMSA) demonstrated that OmpR protein directly binds to the promoter region of soxR (a transcriptional activator of AcrAB-TolC), but not to soxS. Molecular docking predicted a potential interaction between the AI-2 QS signaling molecule and EnvZ protein (binding energy: −23.99 kJ/mol), with hydrogen bonds forming at five amino acid residues. This study provides evidence that OmpR directly binds to the soxR promoter and that AI-2 potentially interacts with EnvZ. These findings offer new mechanistic insights specific to Salmonella pullorum-biofilm (SP-BF) regulation and provide potential targets for biofilm control strategies.

Rice straw biomass-based modified cellulose nanofibers (CNFs): reinforcement in polylactic acid (PLA) bio nanocomposite films

Nanobubble water for the effective removal of biofilm formed by Escherichia coli.

This study investigated the biofilm (BF) formation of a bovine-derived Escherichia coli (E. coli) strain (designated DL1907) and analyzed the factors influencing its formation. The BF-forming capacity, optimal formation time and temperature, as well as the effects of different culture media, pH levels, NaCl concentrations, and glucose concentrations, were assessed using the crystal violet method. The results demonstrated that the strain had a strong BF-forming capacity, achieving the most intact BF structure after 36 h of culture at 37°C. Trypticase Soy Broth (TSB) medium promoted the strongest BF formation compared to Luria-Bertani (LB) and Müller-Hinton Broth (MH) media. The optimal BF growth was achieved at a NaCl concentration of 0.5%, while higher concentrations (> 0.5%) significantly inhibited BF formation. The strain demonstrated a strong capability for BF formation at pH 7, while acidic or alkaline conditions significantly impaired its BF-forming capacity. The minimum BF inhibitory concentrations (MBIC) of baicalin, berberine, andrographolide, and emodin against BF were 512 μg/mL, 64 μg/mL, 64 μg/mL, and 128 μg/mL, respectively. For the antibiotics, the MBIC values of ceftazidime, kanamycin, enrofloxacin, and florfenicol were 256 μg/mL, 128 μg/mL, 64 μg/mL, and 32 μg/mL, respectively. The above experimental results are intended to provide data support for the clearance of the isolated strain DL1907 BF.

Effects of the lpfD gene on biofilm formation in Salmonella.

Background/Objectives: In this study, we aimed to investigate the antimicrobial and antibiofilm activity of seven hydroxyphenyl-thiazolyl-coumarin hybrid compounds with antioxidant properties (1a–g), previously reported by our group. Methods: The compounds were evaluated in vitro through MIC, MBC, and MFC determinations, and percentage of biofilm (BF) inhibition and in silico, respectively, through molecular docking, molecular dynamics simulations, and ADMETox prediction. Results: All compounds showed antibacterial and antifungal activities. In terms of antibacterial activity, all the compounds were active on Pseudomonas aeruginosa (MICs = 15.62–31.25 μg/mL), Enterococcus faecalis (MICs = 15.62–31.25 μg/mL), and Staphylococcus aureus (MICs = 62.5–125 μg/mL). Regarding the antifungal activity, the effect against Candida albicans was similar to fluconazole (MIC = 15.62 μg/mL), compounds 1b and 1g being the most active against Aspergillus brasiliensis (MIC = 15.62 μg/mL). Furthermore, all compounds were both bactericidal and fungicidal. Regarding the antibiofilm activity, compounds 1d–g showed superior P. aeruginosa BF inhibition compared to gentamicin. The in vitro results for the antibacterial activity were well correlated with the observations drawn in the molecular docking studies, where the best binding affinities (BAs) were observed against P. aeruginosa PAO1 GyrB subunit, and the molecular dynamics simulations confirmed the antibacterial mechanism of compounds 1a, 1b, 1d, 1f, and 1g through GyrB subunit inhibition. Regarding the antifungal activity, all compounds showed better BAs than fluconazole against CYP51 in all instances. ADMETox predictions concluded that all the compounds could have low gastrointestinal absorption and reduced risk of pharmacokinetic interactions. Conclusions: The investigated compounds bring novelty into the actual research due to their dual antibacterial and antibiofilm activity against biofilm-associated P. aeruginosa infections.

Objectives: Wound healing and antimicrobial activity are closely linked, as infections can significantly impair healing by affecting granulation tissue development and tensile strength. Bacteria in wounds form bio films and secrete chemicals that disrupt the skin’s defences. This persistent infection hampers the immune cells’ ability to eliminate bacteria, stalling the skin and cell renewal processes. So aqueous peel extracts of Musa paradisiaca, Carica papaya, and Phaseolus vulgaris were studied for antibacterial activity against various bacterial strains. and their wound healing activity is evaluated in combination as a Polyherbal gel(PHG). Materials and Methods: Aqueous extracts of peels of Musa paradisiaca, Carica papaya, and Phaseolus vulgaris were prepared by maceration and antibacterial activity was evaluated against pathogenic strains. A 5% polyherbal gel was prepared using peel extracts to evaluate dermal toxicity and wound healing potential in an incision wound model in rats. Results: the antibacterial activity of Phaseolus vulgaris was highest against Proteus mirabilis (43.25±0.94 mm), followed by Carica papaya (42.95 ± 0.048 mm), and finally, Musa paradisiaca (41.41 ± 0.36 mm), which exhibited the highest antibacterial activity against E. coli. Rats treated with PHG had an earlier epithelialization period (12.6 ± 0.614 days) than the control group. An increase in wound breaking strength of 23.37 ± 0.235 g and raised levels of hydroxyproline of 0.126 ±0.00073 µg were observed in all PHG-treated rats. The PHG formulation developed from the combination of aqueous extracts of Musa paradisiaca, Carica papaya, and Phaseolus vulgaris showed wound recovery effects on various phases of healing cascades. Conclusion: The antimicrobial properties of peel extracts may significantly contribute to improved collagen synthesis, increased wound breaking strength, and decreased microbial load, all of which enhance the wound healing process.

Helicobacter pylori (H. pylori), a prevalent human pathogen affecting nearly half the global population, is a major contributor to chronic gastritis, peptic ulcer, and gastric cancer. H. pylori develops biofilms (BFs) allowing bacteria to evade the immune response. Differences in composition between planktonic and biofilm cells influence the host’s immune response, yet the specific biofilm components modulating this response remain uncharacterized. Considering the above, this study evaluated the effect of in vitro-generated H. pylori BF on the antibacterial activity of neutrophils. This work utilized sonication to obtain disaggregated H. pylori BF (d-BF-Hp) to challenge human neutrophils, assessing their bactericidal and phagocytic activity against Staphylococcus aureus. S. aureus survival in the presence of neutrophils was enhanced by 10 μg/mL of d-BF-Hp’s protein. Conversely, S. aureus survival was significantly lower at 30 µg/mL compared to 10 µg/mL d-BF-Hp. Furthermore, 10 and 30 µg/mL of d-BF-Hp significantly reduced the neutrophil phagocytosis rate. Our findings suggest that d-BF-Hp components diminish neutrophil bactericidal activity, although this effect was not observed at higher d-BF-Hp concentrations. Increased d-BF-Hp concentrations proportionally reduced neutrophil phagocytic capacity. Future work should explore the mechanisms underlying the alteration of neutrophil microbicidal properties.

Introduction: Diabetes-related wounds are worsened by slowed healing and heightened bio-film formation vulnerability, which can result in chronic infections. Epidermal growth factor (EGF) is well known for having regenerating qualities, therefore adding the carboxy-methyl cellulose (CMC) were the hydro gel in preventing the growth of bio films in wounds caused by diabetes. Methods: A 13-week placebo-controlled clinical research with 30 type 2 diabetes patients (17 using CMC hydrogel, 13 using EGF-CMC hydrogel) assessed wound healing in venous ulcers. Swab samples were taken at weeks 2, 7, and 13. Microbiologists and imaging techniques analyzed biofilm formation, microbial load, strain identification, and pathogenic gene expression.Result: Comparing the EGF-CMC a hydrogel to the untreated category, a significant reduction in bio film formation was observed. Reduced numbers of microbes were found by microbiology examination and imaging procedures verified the reduction of the bio film formations. This emerged that the likelihood of separating organisms that produce bio films of injuries given CMC hydrogel formulation were eighty-three percent higher than that from injuries handled with EGF-CMC.Conclusion: The research indicates that isolates with decreased formation of bio film were seen in lesions that received EGF-CMC hydrogel, which is despite the fact of no discernible differences in bacterium counts or genes related to virulence could be identified. This result emphasizes how the reactive covering can affect the bacteria activity in diabetes patients' persistent injuries.

Commonly available essential oils (EOs) are pure aromatic substances derived from natural plant sources (fresh or dried raw materials), with broad biological activity, including antimicrobial activity. The activity of EOs is of great interest due to the serious problem of diseases caused by microorganisms. Pathogenic microorganisms (PAMs) show increased resistance to physical and chemical factors due to their association with a form of specific biological membrane called biofilm (BF), which is resistant to extreme conditions and significantly hinders effective therapy. The decreasing effectiveness of antibiotics, combined with the increasing resistance of microorganisms, has prompted the search for alternative antimicrobial (AM) therapies. EOs and some of their components are currently considered as potential agents useful in the prevention, treatment, and control of infections transmitted by microbial BF. In combination with antibiotics, EOs can prevent the transfer of resistance to AM agents due to the synergistic antibiofilm (ABF) effect. BF inhibition by EO is not based on killing bacterial cells but on the inhibition of the quorum sensing (QS) pathway. EOs also affect growth regulation, nutritional balance, and energy conversion in bacteria. It can be assumed that this group of substances will be of significant importance in the treatment of infectious diseases in the near future. This article reviews the results of the latest research on essential oils and their main components as potential factors limiting/inhibiting the development of PAMs.

EVALUATION OF WASTE WATER TREATMENT AND SOLID WASTE MANAGEMENT USING TITANIUM DIOXIDE BY MOVING BED BIO FILM ( MBBR) TECHNIQUE IN AMBALA CITY

Ambala is crowded district with Approx Sixty Five lakhs and Thirty Five thousand Twenty Seven population including Ambala City, Ambala Sadar, Barara And Naraingarh, During rainy seasons waste from domestic Houses create blockage of sewerage system and effect the solid waste management system. According to district environment plan prepared by ULB In 2023 Ambala City has a Population of 351650 and generates about 158 Solid Waste Generated per day (TPD) On the other hand Ambala Cantt has 31 wards with population of 236850 and 110 Solid Waste Generated per day(TPD) leachate generation is very high in the city due to this people faces problem of heath and Hygiene. In this paper , various methods like MBBR Technique and Leachate Recirculation techniques is discussed to overcome this issue and to increase the efficiency of landfill and solid waste decomposition.

Antibiotics have gain great importance in terms of treatment, as various treatment modalities in different procedures related to dental treatment. In the year of 1976 loeshe has propounded a specific hypothesis of plaque, and since that time there are so many efforts have been made to formulate a periodontal treatment regimen which is based on targeting specific microorganisms which are capable of doing periodontal infections. Periodontitis is found to be the most common disease which is related to the attachment apparatus of the periodontal fibres, and its etiological factors are most commonly found to be the microorganisms which are present in the dental plaque bio films, which constitute of various microorganisms. Along with this the pathogenesis of this disease is also depends upon or we can say influenced by the host response of the patient, that might results in cyclic destruction of the periodontal and surrounding structure as well as disturb the healing pattern of the individual. It has also been stated that, periodontitis can be treated by mechanical debridement by using surgical as well as non surgical procedures. Along with this patient cooperation in maintaining the oral hygiene is also very much important in the success of the surgical or the non surgical procedure. So many times this treatment does not give the desired results, which are expected due to poor patient compliance, which may be due to the altered immune response or with the other factors which are related to the host. This finally leads to the usage of or we can say administration of antibiotics as an adjunct to the other procedure. Antibiotics are very much useful in the elimination of periodontal pathogenic microorganisms. Antibiotics can be administer locally as local drug deleivery system or it can be administer orally, but antibiotics which are administer locally through local drug deleivery system are found to be of very much effective in reducing the inflammation and pain by reducing the number of microorganisms, as this local drug deleivery system provide more amount of antibiotic as it is deleivered locally over the inflammation site. it has also been stated in the literature that, excessive use of antibiotics may results in as averse effects and can also lead to resistant to the specific antibiotic.

A recently calved three-year old Holstein Friesian crossbred cow was presented with the complaint of blood in milk from all four quarters. Clinical examination revealed slight swelling and pain of the udder. Haemato-biochemical parameters of the cow were within the normal range except a low serum calcium. Streptococcus agalactiae was isolated from all the four quarters based on Gram stained morphology, cultural characteristics, biochemical tests and PCR. Multi-drug resistance and bio film formation of the isolate was identified. The animal was treated with Ceftriaxone-tazobactum, tranexamic acid, meloxicam and calcium borogluconate and an uneventful recovery was observed.

An in-depth analysis of microbial response to exposure to high concentrations of microplastics in anaerobic wastewater fermentation

Abstract Casimir forces arise if the spectrum of electromagnetic fluctuations are restricted by boundaries. There is great interest both in fundamental science and technical applications to better understand and technically control these forces. In this work, the influence of five different self‐assembled bio and organic monolayer thin films on the Casimir force between a plate and a sphere is experimentally investigated. It is found that the films, despite being a mere few nanometers thick, reduce the Casimir force by up to 14%. Spectroscopic data indicate a broad absorption band whose presence can be attributed to the mixing of electronic states of the underlying gold layer and those of the molecular film due to charge rearrangement. Using Lifshitz theory, it is calculated that the observed change in the Casimir force is consistent with the measured change in the effective dielectric properties. The nanometer‐sized molecules can penetrate small cavities, and cover any surface with high efficiency. This process seems compatible with current methods in the production of micro‐electromechanical systems (MEMS), which cannot be miniaturized beyond a certain size due to ‘stiction’ caused by the Casimir effect. This approach can therefore offer a practical solution for this problem.

ABSTRACT Hydroxypropyl methylcellulose (HPMC) incorporated bio-composite films (unplasticized and plasticized) were prepared from pregelatinized maize starch/polyvinyl alcohol (PMS/PVA) blends by solution casting method. 10% boric acid (BA) was used as crosslinker. The physico-mechanical properties (tensile strength (TS), elongation at break (%EB), water solubility and moisture uptake) of the bio-composite films were studied. The thermo-chemical stability of the biofilms was studied by FT-IR, TGA and DSC analysis. TS, %EB, water solubility and moisture absorbency of 10% HPMC containing unplasticized films were found 38.1 MPa, 8.5%, 61% and 32.3%, respectively, however, the films were hard and brittle. On the contrary, TS, %EB, water solubility and moisture absorbency of 10% HPMC plasticized films were found 19.2 MPa, 28.5%, 62.2% and 57.3%. The biofilms exhibited relatively low water solubility and moisture uptake compared to higher HPMC containing composite. The thermo-chemical analysis revealed that the HPMC incorporated plasticized film was more thermally stable compared to pure PMS, PVA, HPMC and other bio composite films due to strong hydrogen bonding interaction with BA. The biodegradability of HPMC incorporated plasticized films was confirmed by soil burial test (anaerobic condition, RH 98%, 3 months). Therefore, the plasticized biofilm would be considered an alternative approach for biocompatible packaging material.

Современные нетрадиционные технологии стерилизации являются эффективным методом обработки пи- щевых продуктов и обладают значительными преимуществами по сравнению с термической обработкой. Результаты многочисленных исследований доказали, что высокое гидростатическое давление (HPP), ультрафиолетовое излуче- ние (UV), импульсный свет (PL), ультразвуковая стерилизация (US), импульсное электрическое поле (PEF), облучение и холодная плазма (CP) способны обеззаразить патогены пищевого происхождения, обеспечить безопасность и высо- кое качество продукции, увеличить срок ее хранения, а также сократить время обработки и снизить производственные затраты. Промышленное внедрение этих технологий может стать эффективной альтернативой традиционной терми- ческой обработке. В данный обзор включены статьи за 2010–2023 гг., опубликованные на английском и русском язы- ках. Поиск научной литературы проводили по ключевым словам в библиографических базах Scopus, Web of Science, PubMed и Google Scholar. При отборе публикаций приоритет отдавали источникам с высоким уровнем цитируемости. Использовали методы поиска и скрининга научной литературы, извлечения данных и их анализа, систематизации и обобщения. Обобщены данные об антимикробной активности современных технологий обработки и их воздействии на биопленку. Представлены 7 различных технологий (HPP, UV, PL, US, PEF, облучение, CP), их механизм воздействия на биопленки, инактивацию регулярной микробной активности с повре ждением проницаемо сти клеточной мембраны и воздействием на внутриклеточные компоненты. Результаты обзора могут быть использованы для дальнейших иссле- дований и представляют интерес для предприятий пищевой промышленности с целью внедрения этих технологий для предотвращения загрязнения, вызванного бактериальными биопленками, и поддержания качества продуктов питания. Modern non-traditional sterilization technologies are an effective method of food processing and have signifi cant advantages over heat treatment. Numerous studies have proven that high hydrostatic pressure (HPP), ultraviolet radiation (UV), pulsed light (PL), ultrasonic sterilization (US), pulsed electric fi eld (PEF), irradiation and cold plasma (CP) can effectively decontaminate foodborne pathogens. origin, ensure safety and high quality of products, and also allow you to increase shelf life, reduce processing time and reduce production costs. This review includes articles published in English and Russian between 2010 and 2023. The search for scientifi c literature was carried out using keywords in the bibliographic databases Scopus, Web of Science, PubMed and Google Scholar. When selecting publications, priority was given to sources with a high level of citations. We used methods of searching and screening scientifi c literature, data extraction and analysis, systematization and synthesis. Data on the antimicrobial activity of modern processing technologies and their impact on biofi lm are summarized. 7 different modern technologies are presented (HPP, UV, PL, US, PEF, irradiation, CP), their mechanism of action on biofi lms, inactivation of regular microbial activity with damage to the permeability of the cell membrane and effects on intracellular components. The results of the review may be of interest to the food industry for the implementation of these advanced technologies to prevent contamination caused by bacterial biofi lms, maintain food quality and further research. The industrial implementation of modern food sterilization technologies can become an effective alternative to traditional heat treatment.