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Non-recyclable fiber rejects from paper mills, particularly those from recycled linerboard mills, contain high levels of structural carbohydrates but are currently landfilled, causing financial and environmental burdens. The aim of this study was to develop efficient and sustainable bioprocess to upcycle these rejects into polyhydroxybutyrate (PHB), a biodegradable alternative to degradation-resistant petroleum-based plastics. To achieve high yields of PHB per unit biomass, the specific objective of the study was to investigate various approaches to enhance the hydrolysis yields of fiber rejects to maximize sugar recovery and evaluate the fermentation performance of these sugars using Escherichia coli LSBJ. The investigated approaches included size reduction, surfactant addition, and a chemical-free hydrothermal pretreatment process. A two-step hydrothermal pretreatment, involving a hot water pretreatment (150 °C and 15% solid loading for 10 min) followed by three cycles of disk refining, was found to be highly effective and resulted in an 83% cellulose conversion during hydrolysis. The hydrolysate obtained from pretreated biomass normally requires a detoxification step to enhance fermentation efficiency. However, the hydrolysate obtained from the pretreated biomass contained minimal to no inhibitory compounds, as indicated by the efficient sugar fermentation and high PHB yields, which were comparable to those from fermenting raw biomass hydrolysate. The structural and thermal properties of the extracted PHB were analyzed using various techniques and consistent with standard PHB. [ABSTRACT FROM AUTHOR]

Nucleic acid amplification testing has great potential for point-of-need diagnostic testing with high detection sensitivity and specificity. Current sample preparation is limited by a tedious workflow requiring multiple steps, reagents and instrumentation, hampering nucleic acid testing at point of need. In this study, we present the use of mixed cellulose ester (MCE) paper for DNA binding by ionic interaction under molecular crowding conditions and fluid transport by wicking. The poly(ethylene) glycol-based (PEG) reagent simultaneously provides the high pH for alkaline lysis and crowding effects for ionic binding of the DNA under high salt conditions. In this study, we introduce Paper-based Abridged Solid-Phase Extraction with Alkaline Poly(ethylene) Glycol Lysis (PASAP). The anionic mixed cellulose ester (MCE) paper is used as solid phase and allows for fluid transport by wicking, eliminating the need for pipetting skills and the use of a magnet to retain beads. Following the release of DNA from the cells due to the lytic activity of the PASAP solution, the DNA binds to the anionic surface of the MCE paper, concentrating at the bottom while the sample matrix is transported towards the top by wicking. The paper was washed by dipping it in 40% isopropanol for 10 s. After air-drying for 30 s, the bottom section of the paper (3 mm × 4 mm) was snapped off using the cap of a PCR tube and immersed in the colourimetric loop-mediated isothermal amplification (cLAMP) solution for direct amplification and colourimetric detection. The total sample processing was completed in 15 min and ready for amplification. cLAMP enabled the detection of 102 CFU/mL of Escherichia coli (E. coli) from culture media and the detection of E. coli in milk < 103 CFU/mL (10 CFU) after incubation at 68 °C for 60 min, demonstrating applicability of the method to complex biological samples. [ABSTRACT FROM AUTHOR]

We reported a colorimetric paper-based device by integrating the modified acid RNA-cleaving DNAzymes (MaRCD-EC1) for highly sensitive (detection limit = 102 CFU mL−1), and rapid (within 30 min) detection of E. coli without amplification. This device exhibited a clinical sensitivity of 100% and a specificity of 100% in identifying E. coli-associated urinary tract infections (UTIs) using the clinical urine samples. [ABSTRACT FROM AUTHOR]

In the pursuit of enhancing food packaging, nanotechnology, particularly green silver nanoparticles (G-AgNPs), have gained prominence for its remarkable antimicrobial properties with high potential for food shelf-life extension. Our study aims to develop corn starch-based coating materials reinforced with G-AgNPs. The mechanical properties were examined using a uniaxial tensile tester, revealing that starch coated with the highest G-AgNPs concentration (12.75 ppm) exhibited UTS of 87.6 MPa compared to 48.48 MPa of control paper, a significant (p < 0.02) 65% increase. The assessment of the WVP showcased a statistical reduction in permeability by up to 8% with the incorporation of the hydrophobic layer. Furthermore, antibacterial properties were assessed following ISO 22196:2011, demonstrating a strong and concentration-dependent activity of G-AgNPs against E. coli. All samples successfully disintegrated in both simulated environments (soil and seawater), including samples presenting G-AgNPs. In the food trial analysis, the presence of starch and G-AgNPs significantly reduced weight loss after 6 days, with cherry tomatoes decreasing by 8.59% and green grapes by 6.77% only. The results of this study contribute to the advancement of environmentally friendly packaging materials, aligning with the UN sustainable development goals of reducing food waste and promoting sustainability. [ABSTRACT FROM AUTHOR]

Purpose: Paper aims to evaluate the efficiency of traditional chitosan, nano chitosan, and chitosan nanocomposites for consolidating aged papyrus samples. Cellulose-based materials, such as papyrus sheets and paper, which are the most common types of writing supports for works of art in many museums and archive. They are subjected to different types of deterioration factors that may lead to many conservation problems. Consolidation treatment is one of the most common conservation treatments, which should have perform after much testing to select the appropriate consolidants. Design/methodology/approach: This research paper aims to evaluate the resistance of traditional chitosan, nanochitosan and chitosan/zinc oxide nanocomposite as an eco-friendly papyrus strengthening. Untreated and treated papyrus was thermally aged and characterized via scanning electron microscope (SEM) and Fourier transform infrared spectroscopy (FTIR). Antimicrobial activity of the papyrus specimens was also determined against four tested pathogenic bacteria by disc diffusion method: MRSA, Staphylococcus aureus, E. coli and P. aeruginosa. Findings: The results revealed that chitosan nanocomposite showed a remarkable enhancement of papyrus tensile properties and presence of ZnO prevents the effects of biodeterioration. Originality/value: Zinc oxide nanoparticles enhance the optical properties and increase the chemical reactions between the consolidating material and the treated papyrus. [ABSTRACT FROM AUTHOR]

Paper-based electrochemical sensors have the characteristics of flexibility, biocompatibility, environmental protection, low cost, wide availability, and hydropathy, which make them very suitable for the development and application of biological detection. This work proposes electrospun cellulose acetate nanofiber (CA NF)-decorated paper-based screen-printed (PBSP) electrode electrochemical sensors. The CA NFs were directly collected on the PBSP electrode through an electrospinning technique at an optimized voltage of 16 kV for 10 min. The sensor was functionalized with different bio-sensitive materials for detecting different targets, and its sensing capability was evaluated by CV, DPV, and chronoamperometry methods. The test results demonstrated that the CA NFs enhanced the detection sensitivity of the PBSP electrode, and the sensor showed good stability, repeatability, and specificity (p < 0.01, N = 3). The electrochemical sensing of the CA NF-decorated PBSP electrode exhibited a short detection duration of ∼5–7 min and detection ranges of 1 nmol mL−1–100 μmol mL−1, 100 fg mL−1–10 μg mL−1, and 1.5 × 102–106 CFU mL−1 and limits of detection of 0.71 nmol mL−1, 89.1 fg mL−1, and 30 CFU mL−1 for glucose, Ag85B protein, and E. coli O157:H7, respectively. These CA NF-decorated PBSP sensors can be used as a general electrochemical tool to detect, for example, organic substances, proteins, and bacteria, which are expected to achieve point-of-care testing of pathogenic microorganisms and have wide application prospects in biomedicine, clinical diagnosis, environmental monitoring, and food safety. [ABSTRACT FROM AUTHOR]

Cellulose paper has been studied for its application as an antibacterial filter, due to its robust porous structure, minimal ecological footprint, biocompatibility, and inherent antibacterial properties. Moreover, its properties can be further enhanced via surface functionalization with metallic nanoparticles (NPs) such as silver, zinc, etc. However, the synthesis of metallic NPs is challenging, costly, and environmentally harmful. On the other hand, carbon nanotubes (CNTs) are highly suitable as an additive to cellulose paper due to their high electrical conductivity, excellent mechanical strength, ease of fabrication, and antibacterial properties. In this study, we coated multi-walled carbon nanotubes (MWCNTs) on Hanji, a traditional Korean paper, using a simple dipping method and investigated its antibacterial activity against Escherichia coli (E. coli). The MWCNT-coated Hanji exhibited an inhibition efficiency of ~ 93% against E. coli cells. Moreover, the MWCNT coating resulted in improved mechanical strength, enhanced electrical conductivity, and increased hydrophobicity of the Hanji. Furthermore, it was observed that MWCNTs exhibited exceptionally stable adhesion to the Hanji surface. Our finding shows that MWCNT-coated Hanji could be utilized as an antibacterial material that is used as masks, air pollution filters, and wallpapers in hospitals and residential complexes, and an efficient platform for antiviral studies. [ABSTRACT FROM AUTHOR]

Ag@ceramic composite papermaking pigment was prepared by coating silver onto red ceramic powder using the electroless plating method. SEM and XRD showed that the ceramic pigments have a porous crystalline structure and that silver particles had been successfully loaded onto the surface and into the pores of the Ag@ceramic. Untreated ceramic pigment and Ag@ceramic pigment were incorporated into paper sheets by coating, filling and filling‐coating. Using spinach as an example, the ability of the different papers to preserve food was then evaluated. Four indicators were used to assess the preservative effect of the papers: inhibition of growth of Staphylococcus aureus and Escherichia coli, weight loss of the spinach and retention of vitamin C and chlorophyll in the spinach. Although the ceramic preservative paper has no antibacterial properties, it reduced weight loss from the spinach and increased retention of vitamin C and chlorophyll. The antibacterial preservative papers inhibited the growth of E. coli and S. aureus by >99%, and because of their additional antibacterial activity, these papers preserved the spinach more effectively. The experimental results showed that the antibacterial food‐preservative paper incorporating ceramic pigments had great potential in food packing applications. [ABSTRACT FROM AUTHOR]

The study aimed to explore the nutritional value of sea buckthorn by-products and the antibacterial effects of their extracts on Escherichia coli. The experiment employed the sodium nitrite-aluminum nitrate method to determine flavonoid content, while alcohol extraction and water extraction methods were used to extract active substances from sea buckthorn by-products. The antibacterial effects of sea buckthorn by-product extracts on Escherichia coli were investigated by the filter paper method, perforation method, and broth dilution method. The results showed that the dry matter (DM) content of sea buckthorn by-products was 97.98%, ash content was 3.41%, crude protein (CP) content was 12.87%, and crude fat (EE) content was 22.48%. With the increase of sea buckthorn by-product addition, gas production showed a decreasing trend. Among alcohol extraction and water extraction methods, the constant broth dilution method exhibited the best antibacterial effect. In the alcohol extraction method, the filter paper method showed good antibacterial effect with an inhibition zone of 14.6 mm. In the water extraction method, the filter paper method did not exhibit a significant inhibition zone, and the perforation method was not significant in both alcohol extraction and water extraction methods. The study suggests that sea buckthorn by-products have rich nutritional value, and alcohol extraction is more effective in inhibiting Escherichia coli compared to water extraction. [ABSTRACT FROM AUTHOR]

The aim of this work was to demonstrate the process of manufacturing and applying functionalising additives using a pilot research installation. As part of the optimisation evaluation, hygienic papers functionalised with biopolymer-biocide compositions based on chitosan, starch and Gemini surfactants were prepared. The microbiological properties and susceptibility to biodegradation of prototype hygienic papers (prepared in EPICOM) were assessed In particular, the minimum amount of biopolymer and bioactive agent were determined to ensure the finished product exerted antibacterial activity against Staphylococcus aureus, Bacillus subtilis and Escherichia coli and was more than 90% biodegradable in a compost environment. Under optimal conditions, the hygienic paper exerted excellent antibacterial activity against S. aureus and E. coli as well as good activity against B. subtilis. Moreover, the hygienic paper showed more than 90% biodegradability in compost conditions within 8 weeks. [ABSTRACT FROM AUTHOR]

Microbial xylanase has wide application in bioenergy, animal feed, environmental protection, the pulp and paper industry, and agricultural development. In this study, three xylanases from the microbiota of T. fuciformis with its companion strains were identified by metagenomics sequencing. The three enzymes were subjected to cloning and expression in E. coli or P. pastoris, purification, and characterization for their properties. The results showed that AsXyn1, from Annulohypoxylon stygium, among the three enzymes possessed high thermostability at 40 °C and broad pH tolerance in the range of 2.0–10.0, exhibiting its application potential. Furthermore, it was found that post-translational modification (such as glycosylation) of AsXyn1 enzyme modulated its activity, kinetic parameters, and thermostability. These results and findings provided a hint for enzyme modification and design in future. [ABSTRACT FROM AUTHOR]

Microbial infections are a global health challenge often treated with antibiotics, but their overuse can lead to antibiotic resistance. To address this, there is a need for more efficient personal protective equipment (PPE) with novel antimicrobial techniques. One such technique involves using carbon dots (CDs) to create self-disinfecting fabrics. This study focused on synthesizing phenylboronic-acid-functionalized piperine-based carbon dots (PBA-PPCDs) and boronic acid carbon dots (BACDs) as potential antimicrobial agents. The materials were successfully synthesized using a hydrothermal method and characterized using various techniques to confirm the size, charge, fluorescence properties, and inner morphology of the CDs. The CDs showed bactericidal activity against gram-positive and gram-negative bacteria, with potent inhibition in growth especially in the presence of simulated sunlight. The antibacterial properties of the CDs were tested on cellulose discs, demonstrating strong adherence and significant inhibition of bacterial cells. The cytotoxicity studies showed that these CDs, at concentrations up to 0.1 mg/mL, and the CD-modified fibers are benign to mammalian cells, emphasizing their safety for human use. Overall, the study concluded that PBA-PPCDs and BACDs are promising candidates for modifying fibers and inducing antimicrobial activity in fabrics made of cellulose fibers.Article highlights: New self-disinfecting fabrics kill bacteria with light-activated carbon dots, no harsh chemicals needed. Self-disinfecting fabrics fight bacteria, reduce antibiotic use, and slow superbug growth. Safe and effective: Carbon dot fabrics harmless to humans, promising for PPE. [ABSTRACT FROM AUTHOR]

The freshness and safety of fruits and vegetables affect our daily life. Paper products are often used in the packaging and transportation of fruits and vegetables, and these can provide other functions besides packaging after certain modifications and additions. In this study, the AgNPs/1-MCP antibacterial fresh-keeping composite paper was prepared by in-situ loaded silver nanoparticles and spraying 1-MCP solution. Moreover, the prepared paper was used to preserve sweet cherries. It was found that the prepared AgNPs/1-MCP antibacterial fresh-keeping composite paper could effectively inhibit E. coli and S. aureus. When the addition of 1-MCP in the paper was 0.05 g, the fresh-keeping effect on cherries was the best. Under this optimal condition, the weight loss ratio of the cherries was reduced by 1.93%, the firmness was increased by 27.7%, and the soluble solid content was increased by 25%. The preservation time was extended from 4 days to 12 days, three times that of the untreated ones. The prepared fresh-keeping material is environmentally friendly, non-toxic and harmless, simple to prepare and convenient to use, and is expected to become one of the important fresh-keeping methods for fruits. [ABSTRACT FROM AUTHOR]

As non-biodegradable single-use plastic packaging products have been restricted in recent years, paper-based materials have attracted considerable attention owing to their environmental benefits. However, the hydrophilic nature of paper-based materials limits their application as replacements for non-biodegradable plastics. In this study, an environmentally friendly and multifunctional superhydrophobic paper was developed using silane-modified superhydrophobic nanofibrillated cellulose (M-NFC) via a simple spraying method. This paper can reduce the white pollution caused by non-degradable single-use plastic packaging products. Upon spraying the base paper with 1.5 g/m2 of M-NFC, the coated paper (CP) exhibited excellent superhydrophobicity (water contact angle of 160°), water repellency (Cobb value of 7.5 g/m2), strong durability to sandpaper abrasion, finger-wipe, bending, folding, and sustained exposure to corrosion media (HCl with a pH of 1, NaOH with a pH of 10, high temperature treatment at 180 °C, and ultraviolet irradiation). Additionally, the CP surface directly prevented the adhesion of S. aureus and E. coli and also indirectly repelled solid contaminants upon washing with water, thereby demonstrating highly efficient antibacterial and anti-fouling properties. The durable and multifunctional superhydrophobic paper developed in this study provides a novel direction for solving white pollution and also presents a new research pathway for the potential applications of paper-based materials. [ABSTRACT FROM AUTHOR]

Antibiotic resistance represents a growing medical crisis and is predicted to cause over 10 million deaths globally per year by 2050. Among the most dangerous resistant bacteria are the critical priority pathogens denoted by the World Health Organization (WHO). Fortunately, phage therapy, a high potential treatment method that uses viruses to infect and lyse bacteria, can successfully clear antibiotic-resistant infections. However, it has not passed clinical trials due to the lack of a streamlined process for phage characterization, highlighting the need to compare phage host range determination (HRD) techniques to simplify this process. To address this, phage primary research papers with HRD data were collected from PubMed and Google Scholar. 56 suitable studies were grouped by critical priority pathogen and employed HRD technique. The quantity (mL) of agar, phage filtrate, and bacterial culture used was recorded. Means for each group were compared using a non-parametric ANOVA. For the E. coli O157:H7 research paper group, plaque testing used significantly less total material and agar than spot testing with dilutions (p 5 0.047, p 5 0.041), while spot testing without dilutions used significantly less phage filtrate than plaque testing (p 5 0.035) and significantly less bacterial culture than spot testing with dilutions (p 5 0.013), strongly suggesting that spot testing with dilutions should not be chosen over other methods when conducting HRD as it is the most resource-consumptive. Further investigation into other phage characterization metrics is warranted. [ABSTRACT FROM AUTHOR]

The continuous emergence of new illegal compounds, particularly psychoactive chemicals, poses significant challenges for current drug detection methods. Developing new protocols and kits for each new drug requires substantial time, effort, and dedicated manpower. Whole-cell bacterial bioreporters have been proven capable of detecting diverse hazardous compounds in both laboratory and field settings, identifying not only single compounds but also chemical families. We present the development of a microbial bioreporter for the detection of cocaine, the nervous system stimulant that is the second-most widely used illegal drug in the US. Escherichia coli was transformed with a plasmid containing a bacterial luxCDABEG bioluminescence gene cassette, activated by a cocaine-responsive signaling cascade. The engineered bioreporter is demonstrated to be a sensitive and specific first-generation detection system for cocaine, with detection thresholds of 17 ± 8 μg/L and 130 ± 50 μg/L in a buffer solution and in urine, respectively. Further improvement of the sensor's performance was achieved by altering the nucleotide sequence of the PBen gene promoter, the construct's sensing element, using accelerated site-directed evolution. The applicability of ready-to-use paper strips with immobilized bioreporter cells was demonstrated for cocaine detection in aqueous solutions. [ABSTRACT FROM AUTHOR]

Hybrid kinetic models, linking structured models of cell (nano-scale) metabolic processes to the dynamics of macroscopic variables of the bioreactor, are proven to lead to more precise predictions of all key-species dynamics under variable operating conditions, being of an exceptional importance in engineering evaluations to in-silico (math-model-based) determine the optimal operating mode of a fed-batch bioreactor (FBR). Even if such extended dynamic models require more experimental and computational efforts, their use has proven to be advantageous. The approached probative example refers to the simulation of the dynamics of some key species of the central carbon metabolism (CCM) of a modified E. coli cell, linked to the state variables of a FBR used for the tryptophan (TRP) production. By using several optimization algorithms, and an original application of the Pareto-optimal front technique, this paper compares various operating alternatives by using multiple control variables, aiming to maximize TRP production, with minimum substrate consumption. The used E. coli strain was modified to drastically amplify the glucose (GLC) uptake into the cell. [ABSTRACT FROM AUTHOR]

Purpose: The purpose of this paper is to assess the microbiological safety of aloe-based dietary supplements available on the Polish market. The study investigates how the form of the aloe supplement (juice vs. capsules) and the storage time affect microbial contamination levels, emphasizing the importance of quality management and risk management in ensuring the safety of plant-based supplements. Design/methodology/approach: The study focused on assessing the microbiological stability of 68 aloe-based dietary supplements, including Aloe vera juice and gel-shell capsules, at two key time points: immediately after opening (time 0) and at the final storage period (time K). Microbiological analysis included testing for the presence of aerobic mesophilic bacteria, yeasts, molds, Staphylococcus aureus, and Escherichia coli, alongside an evaluation of the active acidity and microbiological stability in the juice preparations. The research methodology emphasized a comprehensive laboratory-based approach to evaluate the impact of the supplement form (juice vs. capsules) and storage duration on microbial contamination. By focusing on the end-user stages, the study indirectly addressed risk management by identifying potential contamination risks linked to product form and storage. Additionally, quality management principles were applied through the systematic assessment of supplements' compliance with microbiological safety standards. Findings: The study found that S. aureus and E. coli were absent in all samples, with 18% of the samples free from any microbial contamination. Aloe capsules were more prone to fungal contamination compared to juices. Juices demonstrated greater microbiological stability, with approximately 19% stability compared to around 11% for capsules. These findings underscore the importance of rigorous quality control to ensure the microbiological safety of aloe supplements and highlight the need for ongoing post-market monitoring to mitigate potential health risks. Research limitations/implications: The study focused specifically on aloe supplements from the Polish market, which may limit its generalizability to other types of plant-based supplements. Future research could broaden the scope to include other popular plant supplements, such as young barley, to compare microbiological stability and safety across different categories of plant-based products. This would provide a more comprehensive view of potential risks and quality control measures needed for various supplements. Practical implications: The research underscores the need for enhanced quality control measures during the production, storage, and distribution of aloe supplements. Manufacturers should implement risk management strategies to reduce contamination risks, particularly in capsule-based products, and improve hygiene practices to meet safety standards. These findings could influence regulatory policies and encourage more rigorous post-market surveillance of dietary supplements. Social implications: The study highlights the potential risks associated with the uncontrolled consumption of plant-based supplements and emphasizes the importance of ensuring their safety. The findings can contribute to promoting more responsible supplement use and may encourage stricter regulatory frameworks, ultimately improving public health and enhancing consumer protection. Originality/value: This study provides new insights into the microbiological safety of aloebased dietary supplements available on the Polish market. It contributes to the fields of quality management and risk management in dietary supplements by offering valuable information for manufacturers, regulators, and health professionals. Additionally, the findings are relevant for consumers, as they highlight the importance of product safety and informed usage. [ABSTRACT FROM AUTHOR]

Background: Understanding the aetiological organisms causing maternal infections is crucial to inform antibiotic treatment guidelines, but such data are scarce from Sub-Saharan Africa (SSA). We performed this systematic review and meta-analysis to address this gap. Methods: Microbiologically confirmed maternal infection data were collected from PubMed, Embase, and African Journals online databases. The search strategy combined terms related to bacterial infection, pregnancy, postnatal period, observational studies, SSA. Exclusion criteria included colonization, asymptomatic infection, and screening studies. Pooled proportions for bacterial isolates and antimicrobial resistance (AMR) were calculated. Quality and completeness of reporting were assessed using the Newcastle–Ottawa and STROBE checklists. Findings: We included 14 papers comprising data from 2,575 women from four sources (blood, urine, surgical wound and endocervical). Mixed-growth was commonly reported at 17% (95% CI: 12%-23%), E. coli from 11%(CI:10%-12%), S. aureus from 5%(CI: 5%-6%), Klebsiella spp. at 5%(CI: 4%- 5%) and Streptococcus spp. at 2%(CI: 1%-2%). We observed intra-sample and inter-sample heterogeneity between 88–92% in all meta-analyses. AMR rates were between 19% -77%, the highest with first-line beta-lactam antibiotics. Convenience sampling, and limited reporting of laboratory techniques were areas of concern. Interpretation: We provide a comprehensive summary of microbial aetiology of maternal infections in SSA and demonstrate the paucity of data available for this region. We flag the need to review the current local and international empirical treatment guidelines for maternal bacterial infections in SSA because there is high prevalence of AMR among common causative bacteria. Funding: This research was supported by the NIHR-Professorship/NIHR300808 and the Wellcome-Strategic-award /206545/Z/17/Z. Trial registration: Prospero ID CRD42021238515. [ABSTRACT FROM AUTHOR]

The green synthesis of metal oxide nanoparticles using plant extracts can effectively replace traditional chemical synthesis methods. In present paper, we describe the formation of zinc oxide (ZnO) nanoparticles (NPs) using Pistacia vera soft peel extract. Synthesis of plant-based nanoparticles possesses numerous advantages compared to the conventional physicochemical approaches with different applications in biology and medicine. In the present study Pistacia vera peel extract was used to synthesize ZnO NPs. To investigate the optical and structural features of ZnO nanoparticles synthesized by Pistacia vera peel extract, X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, ultraviolet-visible spectrophotometer (UV-Vis), and scanning electron microscope (SEM) were used. The off-yellow hue of the reaction mixture indicated that ZnO NPs were formed. The presence of Pistacia vera peel extract-mediated ZnO NPs was revealed by UV-Visible peaks at 422 nm. In addition, an XRD pattern confirmed the formation of spherical structure nanomaterials with an average size of 42 nm along with the XRD pattern matching the JCPDS card. The Existence of bioactive functional groups effective in reducing the bulk of zinc sulfate to ZnO NPs was further confirmed by FTIR. The SEM images revealed the spherical shape, and the size of nanoparticles, which was within the range of 31.14 to 48 nm. To examine the antibacterial potential of ZnO NPs, a paper disc diffusion technique was used against Gram-negative Escherichia coli and Gram-positive Staphylococcus aureus clinical strains in terms of the inhibition zone. In addition, the radical scavenging assay was done by the DPPH test. The green synthesized Pistacia peel extract-mediated ZnO NPs demonstrate striking antioxidative activity at 100 μg mL–1. Using NaBH4, nanoscale zinc oxide can remove methylene blue in only 150 seconds. Furthermore, they remove 98% of methylene blue in 14 minutes under UV light. [ABSTRACT FROM AUTHOR]

Uropathogenic Escherichia coli (UPEC) causes up to 90% of urinary tract infections (UTI) which is more prevalent among females than males. In urine, patients with symptomatic UTI usually have a high concentration of bacterial infection, ≥ 105 colony-forming units (CFU) per mL, in which the culture method is regularly the gold standard diagnosis. In this study, a simple and inexpensive distance-based paper device (dPAD) combined with the fluorescent closed tube LAMP assay was validated for simultaneously screening and semi-quantifying the infection level of E. coli in 440 urine samples of patients with UTI. The dPAD could measure the LAMP amplicons and semi-quantify the levels of E. coli infection in heavy (≥ 104 CFU/mL), light (≤ 103 CFU/mL) and no infection. The sensitivity and specificity had reliable performances, achieving as high as 100 and 92.7%, respectively. The one step LAMP assay could be performed within 3 h, which was 7.5 times faster than the culture method. To empower early UTI diagnosis and fast treatment, this inexpensive dPAD tool combined with the fluorescent closed tube LAMP assay is simple, reliably fast and practically portable for point-of-care settings, particularly in resource-limited areas, which can be set up in all levels of healthcare facilities. [ABSTRACT FROM AUTHOR]

Background: The utilization of antibiotic adjuvants presents a promising strategy for addressing bacterial resistance. Recently, the development of antibiotic adjuvants has attracted considerable attention from researchers in academia and industry. This study aimed to identify the most influential publications on antibiotic adjuvants and elucidate the hotspots and research trends in this field. Method: Original articles and reviews related to antibiotic adjuvants were retrieved from the Web of Science Core Collection database. The top 100 highly cited publications were selected and the visual analyses of publication outputs, countries, institutions, authors, journals, and keywords were conducted using Excel, VOSviewer, or CtieSpace software tools. Results: The top 100 cited publications concerning antibiotic adjuvants spanned the years 1977-2020, with citation counts ranging from 174 to 2,735. These publications encompassed 49 original articles and 51 reviews. The journal "Antimicrobial Agents and Chemotherapy" accounted for the highest number of publications (12%). The top 100 cited publications emanated from 39 countries, with the United States leading in production. Institutions in Canada and the United States exhibited the most substantial contributions to these highly cited publications. A total of 526 authors participated in these studies, with Robert E. W. Hancock, Laura J. V. Piddock, Xian-Zhi Li, Hiroshi Nikaido, and Olga Lomovskaya emerging as the most frequently nominated authors. The most common keywords included "E. coli", "P. aeruginosa", "S. aureus", "in-vitro activity", "antimicrobial peptide", "efflux pump inhibitor" "efflux pump", "MexAB-OprM" and "mechanism". These keywords underscored the hotspots of bacterial resistance mechanisms and the development of novel antibiotic adjuvants. Conclusion: Through the bibliometric analysis, this study identified the top 100 highly cited publications on antibiotic adjuvants. Moreover, the findings offered a comprehensive understanding of the characteristics and frontiers in this field. [ABSTRACT FROM AUTHOR]

Microorganisms are a promising source of colorants with large economic potential. Owing to better bio-degradability and higher eco-compatibility, microbial pigments propose promising avenues and can thus be a smart substitute for artificial pigments. The present work focused on the screening, isolation, and extraction of a blue-green pigment produced by soil microorganisms. The pigment-producing microorganism was identified as Pseudomonas aeruginosa on the basis of standard biochemical tests and by 16S rRNA sequencing. The purified blue pigment was characterized by high-performance liquid chromatography and gas chromatography–mass spectrometry. The antimicrobial activity of the microbial biocolor (3 × 108 CFU/ml) was studied, and the zone of inhibition was found to be 10 mm, 13 mm, 9 mm, and 7 mm for E. coli, S. aureus, B. subtilis, and S. typhi, respectively. The evaluation of the biocolor as a dye was executed on different types of textiles and paper. The dyed fabrics were checked for washing, rubbing, and light and temperature fastness. Standard fabric properties of the fabrics dyed with the extracted microbial pigment were also assessed. The dyed fabrics were finally subjected to a patch test to check for any kind of allergic or hypersensitivity on human skin. The extracted pigment from Pseudomonas aeruginosa exhibited remarkable dyeing properties, indicating the scope for utilization of the pigment as a colorant on different types of textile and paper materials. The present study highlights the application of a bacterial pigment as a dyeing agent, which may raise its market value and probably replace toxic synthetic dyes due to its nontoxic nature, compatibility with various textiles, and cost-effectiveness. [ABSTRACT FROM AUTHOR]

Wounds often develop infections caused by microbes. Preventing these microbes from causing infection is essential for wound healing. The current study therefore focuses on the preparation of an Fp (cellulose) scaffold coated with antimicrobial clindamycin drug (Cl) and chitosan (Cs) for use in wound dressings. Fp was used as a control. Before testing the efficacy of ClCFp scaffolds against bacterial strains and evaluating their cytocompatibility, they were thoroughly characterized using microscopic, spectroscopic, BET, and X-ray techniques. These methods confirmed coating of Cs and Cl drug on Fp. No significant structural damage to the Fp was observed. The porosity and surface area were found to decrease with coating. Invitro studies with HGF cells showed that the cells not only adhered to the scaffolds and proliferated, but also exhibited good viability. The results of the antibacterial tests showed that ClCFp scaffold was effective against both E. coli, "gram-negative" bacteria, and S. aureus, "gram-positive bacteria". Docking studies performed for the transcription termination factor Rho of E. coli and penicillin-binding protein 2 of S. aureus against the Cl drug confirmed the interaction between the Cl drug and bacterial proteins. Therefore, the ClCFp composite scaffolds have good prospects for biomedical applications and especially for wound dressings. [ABSTRACT FROM AUTHOR]

Insufficiently treated wastes contained within onsite sanitation systems (OSS) commonly used by disadvantaged and developing communities contribute to public and environmental health concerns, calling for practical alternative solutions. At the basic level, an improved understanding of the evolution of chemical and physical constituents under different waste introduction methods and for short-term and long-term operation is needed. While receiving non-dilute waste under mixed, unmixed, toilet paper exclusion, and urine diversion (UD) regimes, self-flushing OSS simulated using anaerobic digesters (ADs) were compared during three operational stages: (1) 0–1 month service for unsheltered encampments; (2) 1–3 month disaster relief scenario; and (3) ≥ 3 months representing refugee camps and long-term household use. Although stratification was found to promote suitable conditions for short-term use of self-flushing toilets, mixing increased beneficial biodegradation of organic constituents. Urine-containing ADs demonstrated a shift from sulfide to ammonia odor accompanied by high pH (> 8) after ~ 240 d. E. coli reduction following elevated nitrogen and dissolved solids levels pointed to decreased pathogen survival in ADs with urine. The benefits of bacterial disinfection, reduction of sulfurous odors, and heightened organics degradation in mixed, urine-containing ADs suggest this format as more desirable for prolonged use of self-flushing OSS over unmixed or urine-diverting formats. [ABSTRACT FROM AUTHOR]

Melamine-impregnated paper is made by impregnating paper with melamine-formaldehyde resin and can be hot-pressed and laminated onto the surface of wood boards. If the paper has antibacterial activity, it can prevent the spread of indoor bacteria, but impregnated paper with a long-term antibacterial effect has not been proposed. Metal–organic frameworks (MOFs) have been studied as a reservoir of metal ions. In this study, a silver-metal organic framework (Ag-BTC) was synthesized by a green and scalable method at 60 °C (A-60) and at room temperature (A-25). The structure and thermal stability of the Ag-BTC were characterized. Compared with A-25, the structure and particle size distribution of A-60 were more regular and uniform. The thermal stability and the compatibility of Ag-BTC and MF resin were suitable for hot-pressing process. Ag-BTC in the cured impregnated paper exhibited the sustained-release performance of Ag+. The antibacterial ratio of decorated blockboards with 0.10 wt% A-25 to E. coli and S. aureus exceeded 99.99%, reaching Level I antibacterial grade. Compared with A-60-decorated blockboards, the better antibacterial activity of A-25-decorated blockboards was due to the release of more Ag+. This study provides new ideas for the design of antibacterial melamine-impregnated paper. [ABSTRACT FROM AUTHOR]

Diagnostic assays for developing countries have a prerequisite of low-cost along with high sensitivity and specificity. Paper, a commonly available material, provides a great economical and portable platform for fabricating biosensors. The present work focuses on the fabrication of a paper-based analytical device (PAD) using commonly accessible materials. The electrodes have been drawn using a pencil followed by filling with in-house prepared graphite ink and the barrier wall around the detection/sample zone has been prepared using a glue gun. The PAD has been developed in 2-dimensional (2D) and 3-dimensional (3D) designs. The principle of antibody-antigen interactions has been used for the realization of an economical and highly selective paper-based biosensor for E. coli O157:H7, paving way for economically weaker sections of the society to monitor their health. The electrochemical measurement results on paper substrate have turned out to be highly promising for the advancement of paper-based point-of-care (POC) diagnostics for pathogens like E. coli O157:H7. [ABSTRACT FROM AUTHOR]

lysine is an essential amino acid with significant importance, widely used in the food, feed, and pharmaceutical industries. To meet the increasing demand, microbial fermentation has emerged as an effective and sustainable method for L-lysine production. Escherichia coli has become one of the primary microorganisms for industrial L-lysine production due to its rapid growth, ease of genetic manipulation, and high production efficiency. This paper reviews the recent advances in E. coli strain engineering and fermentation process optimization for L-lysine production. Additionally, it discusses potential technological breakthroughs and challenges in E. coli-based L-lysine production, offering directions for future research to support industrial-scale production. [ABSTRACT FROM AUTHOR]

lysine is an essential amino acid with significant importance, widely used in the food, feed, and pharmaceutical industries. To meet the increasing demand, microbial fermentation has emerged as an effective and sustainable method for L-lysine production. Escherichia coli has become one of the primary microorganisms for industrial L-lysine production due to its rapid growth, ease of genetic manipulation, and high production efficiency. This paper reviews the recent advances in E. coli strain engineering and fermentation process optimization for L-lysine production. Additionally, it discusses potential technological breakthroughs and challenges in E. coli-based L-lysine production, offering directions for future research to support industrial-scale production. [ABSTRACT FROM AUTHOR]

Escherichia coli (E. coli) is a ubiquitous symbiotic bacterium in the gut, and the diversity of E. coli genes determines the diversity of its functions. In this review, the two‐edged sword theory was innovatively proposed. For the question 'how can we harness the ambivalent nature of E. coli to screen and treat CRC?', in terms of CRC screening, the variations in the abundance and subtypes of E. coli across different populations present an opportunity to utilise it as a biomarker, while in terms of CRC treatment, the natural beneficial effect of E. coli on CRC may be limited, and engineered E. coli, particularly certain subtypes with probiotic potential, can indeed play a significant role in CRC treatment. It seems that the favourable role of E. coli as a genetic tool lies not in its direct impact on CRC but its potential as a research platform that can be integrated with various technologies such as nanoparticles, imaging methods, and synthetic biology modification. The relationship between gut microflora and CRC remains unclear due to the complex diversity and interaction of gut microflora. Therefore, the application of E. coli should be based on the 'One Health' view and take the interactions between E. coli and other microorganisms, host, and environmental factors, as well as its own changes into account. In this paper, the two‐edged sword role of E. coli in CRC is emphasised to realise the great potential of E. coli in CRC screening and treatment. [ABSTRACT FROM AUTHOR]

Simple Summary: Endometritis is a prevalent disease in perinatal dairy cows, which leads to compromised reproductive function. Studies have confirmed that A20, also known as TNFAIP3, can regulate inflammatory responses in various cells. However, it remains unclear whether A20 regulates the inflammatory response of bovine endometrial cells and if autophagy plays a role in A20's regulation of inflammatory responses. In this paper, we show that elevated expression of A20 is linked to the progression of endometritis in dairy cows. A20 inhibited the activation of the NF-κB pathway and the mRNA expression levels of proinflammatory cytokines in LPS-induced bovine endometrial epithelial cells. Moreover, it enhanced autophagic activity in the bovine endometrial epithelial cells inhibited by LPS. Our study further showed that A20 mitigated the inflammatory response of bovine endometrial epithelial cells by promoting autophagy. These findings will enhance our understanding of the pathogenesis and provide novel insights for the prevention and treatment of endometritis in dairy cows. Endometritis represents a prevalent condition in perinatal dairy cows. Bovine endometrial epithelial cells (BEECs), as the primary interface between cavity and the external environment, are particularly vulnerable to infection by pathogenic bacteria following parturition. A20 is essential for regulating inflammation and modulating immune responses. Nevertheless, the exact role of A20 in the BEECs in response to inflammatory response is not fully understood. An endometritis model infected by Escherichia coli (E. coli) in vivo and a BEECs inflammation model induced with lipopolysaccharide (LPS) in vitro were built to investigate the function and governing mechanisms of A20 in endometritis. The results showed that infection with E. coli resulted in endometrial damage, inflammatory cell infiltration, and upregulation of inflammatory factors in dairy cows. Furthermore, A20 expression was upregulated in the endometrium of cows with endometritis and in BEECs following LPS stimulation. A20 overexpression attenuated the level of proinflammatory cytokines in LPS-stimulated BEECs; conversely, A20 knockdown lead to an exacerbated response to LPS stimulation. The overexpression of A20 was shown to activate autophagy and suppress the NF-κB signaling pathway in LPS-stimulated BEECs. However, blocking autophagy with chloroquine notably attenuated the anti-inflammatory effect of A20, leading to the activation of the NF-κB signaling pathway. In summary, the study demonstrated that A20's suppression of inflammation in LPS-stimulated BEECs is associated with the activation of autophagy. Therefore, the A20 protein showed potential as a novel treatment focus for managing endometritis in dairy cows. [ABSTRACT FROM AUTHOR]

In this paper, a series of tetrameric surfactants (4CnSAZs, n = 12, 14, 16) endowed with zwitterionic characteristic were synthesized by a simple and convenient method and their structures were characterized by FT-IR, 1H NMR and elemental analysis. Their physicochemical properties were studied using the Wilhelmy plate method, fluorescence spectra and dynamic light scattering technique. 4CnSAZs have higher surface activities and tend to adsorb at the air/water surface rather than self-assembling in aqueous solution. The thermodynamic parameters obtained from surface tension measurements show that both processes of adsorption and micellization of 4CnSAZs are spontaneous and that the micellization processes of 4CnSAZs are entropy-driven processes. Both adsorption and micellization of 4CnSAZs are inclined to occur with the increase of alkyl chain length or temperature. For 4C12SAZs, there are only small-size aggregates (micelles), while the large aggregates (vesicles) are observed at the alkyl length of 4CnSAZs of 14 or 16. This shows that the alkyl chain length for oligomeric surfactants has a greater sensitivity for aggregate growth. The aggregate morphologies obtained from the calculated values of critical packing parameter (p) for 4C14SAZs and 4C16SAZs can be supported by the DLS measurement results. The test results obtained by the separation-water-time method show that 4CnSAZs have good emulsification performance and that the prepared emulsions appear to exit in the form of multiple emulsions. In addition, 4CnSAZs have good antibacterial activities against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus). The present study reveals the unique behavior of a zwitterionic tetrameric surfactant and may give new insights into molecular design and synthesis of a high degree of surfactants with different structure characteristics for potential application in various industrial fields. [ABSTRACT FROM AUTHOR]

Background: Ensuring the availability of safe drinking water remains a critical challenge in developing countries, including Ethiopia. Therefore, this paper aimed to investigate the prevalence of fecal coliform and E. coli bacteria and, geographical, children availability, and seasonal exposure assessment through a meta-analysis. Methods: Two independent review groups extensively searched internet databases for English-language research articles published between 2013 and 2023. This systematic review and meta-analysis followed PRISMA guidelines. The methodological quality of each included study was evaluated using the STROBE guidelines. Publication bias was assessed by visual inspection of a funnel plot and then tested by the Egger regression test, and meta-analysis was performed using DerSimonian and Laird random-effects models with inverse variance weighting. Subgroup analyses were also conducted to explore heterogeneity. Results: Out of 48 potentially relevant studies, only 21 fulfilled the inclusion criteria and were considered for meta-analysis. The pooled prevalence of fecal coliform and E. coli was 64% (95% CI: 56.0–71.0%, I2 = 95.8%) and 54% (95% CI: 45.7–62.3%, I2 = 94.2%), respectively. Subgroup analysis revealed that the prevalence of fecal coliform bacteria increased during the wet season (70%) compared to the dry season (60%), particularly in households with under-five children (74%) compared to all households (61%), in rural (68%) versus urban (66%) areas, and in regions with high prevalence such as Amhara (71%), Gambela (71%), and Oromia (70%). Similarly, the prevalence of E. coli was higher in households with under-five children (66%) than in all households (46%). Conclusions: The analysis highlights the higher prevalence of fecal coliform and E. coli within households drinking water, indicating that these bacteria are a significant public health concern. Moreover, these findings emphasize the critical need for targeted interventions aimed at improving drinking water quality to reduce the risk of fecal contamination and enhance public health outcomes for susceptible groups, including households with under-five children, in particular geographical areas such as the Amhara, Gambela, and Oromia regions, as well as rural areas, at point-of-use, and during the rainy season. Registration: This review was registered on PROSPERO (registration ID - CRD42023448812). [ABSTRACT FROM AUTHOR]

Antibacterial dressings play an important role in wound management, especially in chronic wounds. Due to the excellent water retention, antibacterial hydrogel has become an ideal wound dressing. In this paper, the effective antibacterial dressing was constructed with the poly N-isopropylacrylamide (PNIPAM) hydrogel and graphene oxide loading nanosilver particles (GO-Ag) by the in situ chemical crosslinking method. The molecular structure, viscosity and mechanical properties, antibacterial agent content, antibacterial performance, temperature-sensitive antibacterial relationship and biocompatibility of PNIPAM-based GO-Ag composite hydrogel (PNIPAM/GO-Ag) were systematically characterized by the scanning electron microscopy (SEM), infrared spectroscopy (FT-IR), plate counting and other methods. The results showed that the introduction of GO-Ag increased the pore structure of PNIPAM/GO-Ag hydrogel and provided more active sites for the release of silver nanoparticles, wherein the content of nanosilver in PNIPAM/GO-Ag hydrogel was only 0.01%, meeting the requirements of application as antibacterial dressings. Moreover, when the hydrogel was subjected to heat contraction, silver nanoparticles could release more quickly and efficiently. The antibacterial rates of the PNIPAM/GO-Ag hydrogel against E. coli and S. aureus were 99.8 and 99% at 37 °C, respectively, higher than those at 25 °C (92, 95%). Compared with the pure PNIPAM hydrogel (1423.0%), the swelling rate of PNIPAM/GO-Ag hydrogel could reach 2024.6%, certifying its ability to absorb exudate of wound site. When the deformation was less than 80%, the hydrogel could maintain excellent elastic deformation recovery ability, and the viscosity of hydrogel at human body temperature was 38 Pa·s. These prove that it had a good fit with the skin, could dissipate more energy and restore shape. The hemolysis rate of PNIPAM/GO-Ag hydrogel was less than 5%, showing good bio-safety. These all demonstrated the PNIPAM/GO-Ag hydrogel can be used as a potential application for the skin wound dressing. [ABSTRACT FROM AUTHOR]

The tricyclic-aromadendrene-type sesquiterpenes are widely distributed and exhibit a range of biological activities, including anti-inflammatory, analgesic, antioxidant, antibacterial, insecticidal and cytotoxic properties. Several key sesquiterpene synthases (STSs) of this type have been identified, of which, viridiflorol synthase has been engineered for efficiently biosynthesizing viridiflorol in an Escherichia coli strain. This paper comprehensively summarizes the distribution and biological activity of aromadendrene-type sesquiterpenes in plant essential oils and microorganisms. The progress in aromadendrene-type sesquiterpene biosynthesis research, including the modifications of key STSs and the optimization of synthetic pathways, is reviewed. Finally, the prospects and associated challenges for the application and biosynthesis of these natural products are also discussed. [ABSTRACT FROM AUTHOR]

This paper presents an optimal tuning of a proportional integral differential (PID) controller used to maintain glucose concentration at a desired set point. The PID controller synthesizes an appropriate feed rate profile for an E. coli fed-batch cultivation process. Mathematical models are developed based on dynamic mass balance equations for biomass, substrate, and product concentration of the E. coli BL21(DE3)pPhyt109 fed-batch cultivation for bacterial phytase extracellular production. For model parameter identification and PID tuning, a hybrid metaheuristic technique—chaotic electromagnetic field optimization (CEFO)—is proposed. In the hybridization, a chaotic map is used for the generation of a new electromagnetic particle instead of the electromagnetic field optimization (EFO) search strategy. The CEFO combines the exploitation capability of the EFO algorithm and the exploration power of ten different chaotic maps. The comparison of the results with classical EFO shows the superior behaviour of the designed CEFO. An improvement of 30% of the objective function is achieved by applying CEFO. Based on the obtained mathematical models, 10 PID controllers are tuned. The simulation experiments show that the designed controllers are robust, resulting in a good control system performance. The closed-loop transient responses for the corresponding controllers are similar to the estimated models. The settling time of the control system based on the third PID controller for all estimated models is approximately 9 min and the overshoot is approximately 15%. The proposed CEFO algorithm can be considered an effective methodology for mathematical modelling and achievement of high quality and better performance of the designed closed-loop system for cultivation processes. [ABSTRACT FROM AUTHOR]

The study investigates four paper-based materials designed for short-time wrapping of meat products by determining morpho-structure, capillary-hydroscopic, barrier and antibacterial properties, wettability and migration into food simulants. The paper-based materials are coded as RO, SP, IT and SLO. RO and SLO samples exhibit the best barrier properties against water vapors. The low solubility and contact angles of RO, IT and SLO in A simulant (distilled water) make them suitable for aqueous food storage. The extremely high solubility of SP and SLO in simulant B (acetic acid) shows that wax and hydrophobized starch, respectively are carried by the acidic media, thus these agents are unlikely to coat the paper designed to package acidic food. SLO inhibits E. coli, Salmonella enterica, Lysteria monocytogenes, Pseudomonas aeruginosa and fluorescens. Polyethylene coated on RO and IT surface and wax impregnated on SP have a lower antimicrobial activity in comparison with hydrophobized starch coated on SLO. [ABSTRACT FROM AUTHOR]

The rapid and specific point-of-care (POC) analysis of virulent pathogenic strains plays a key role in ensuring food quality and safety. In this work, a paper-based fluorescent phage biosensor was developed for the detection of the virulent E. coli O157:H7 strain (as the mode of virulent pathogens) in food samples. Firstly, phages that can specifically combine with E. coli O157:H7 (E. coli) were stained with SYTO-13 dye to prepare a novel fluorescent probe (phage@SYTO). Simultaneously, a micro-porous membrane filter with a pore size of 0.45 μm was employed as a paper chip so as to retain the E. coli-phage@SYTO complex (>1.2 μm) on its surface. The phage@SYTO (200 nm in size) was able to pass through the pores of the chip, and the complex could be retained on the paper chip using the free phage@SYTO probes. The E. coli-phage@SYTO could emit a visual fluorescent signal (excited at 365 nm; emitted at 520 nm) onto the chip, which could be detected by a smartphone to reflect the concentration of E. coli. Under optimized conditions, the detection limit was as low as 50 CFU/mL (S/N = 3) and exhibited a wide linear range from 102 to 106 CFU/mL. The sensor has potential application value for the quick and specific POCT detection of virulent E. coli in foods. [ABSTRACT FROM AUTHOR]

Background: The emergence and rapid spread of gram-negative bacteria resistant to carbapenems among newborns is concerning on a global scale. Nonetheless, the pooled estimate of gram-negative bacteria resistant to carbapenem that cause neonatal sepsis in developing nations remains unknown. Thus, this study aimed to determine the combined prevalence of gram-negative bacteria resistant to carbapenem in African newborns who were suspected of having sepsis. Methods: All studies published from January 1, 2010, up to December 30, 2023, from PubMed, Science Direct, Scopus electronic databases, and the Google Scholar search engine were researched. Isolates tested for carbapenem from neonates with sepsis, English language papers conducted in Africa, and cross-sectional and cohort studies papers were included. Using PRISMA guidelines, we systematically reviewed and meta-analyzed studies that assessed the prevalence of carbapenem-resistant gram-negative bacteria. The "Joanna Briggs Institute" was used critically to evaluate the quality of the included studies. The data analysis was carried out using STATA™ version 17. Heterogeneity across the studies was evaluated using Q and I 2 tests. The subgroup analysis was done and, funnel plot and Egger's regression test were used to detect publication bias. A sensitivity analysis was conducted. Results: All 36 studies were included in the meta-analysis and systematic review. The pooled prevalence of carbapenem resistance in Africa was 30.34% (95% CI 22.03–38.64%). The pooled estimate of gram-negative bacteria resistant to imipenem, and meropenem was 35.57% (95% CI 0.67–70.54%) and 34.35% (95% CI 20.04% – 48.67%), respectively. A. baumannii and Pseudomonas spp. had pooled prevalence of 45.9% (95% CI 33.1–58.7%) and 43.0% (95% CI 23.0–62.4%), respectively. Similarly, Pseudomonas spp. and A. baumannii also exhibited strong meropenem resistance, with a pooled prevalence of 29.2% (95% CI 4.8–53.5%) and 36.7% (95% CI 20.1–53.3%), respectively. E. coli and K. pneumoniae were the two most common isolates. Conclusion: There should be urgent antimicrobial stewardship practices, strengthened surveillance systems and effective treatment for neonates with sepsis. There was remarkable variation in resistance across the continent. [ABSTRACT FROM AUTHOR]

A restriction endonuclease (RE) is an enzyme that can recognize a specific DNA sequence and cleave that DNA into fragments with double-stranded breaks. This sequence-specific cleaving ability and its ease of use have made REs commonly used tools in molecular biology since their first isolation and characterization in 1970s. While artificial REs still face many challenges in large-scale synthesis and precise activity control for practical use, searching for new REs in natural samples remains a viable route to expanding the RE pool for fundamental research and industrial applications. In this paper, we propose a new strategy to search for REs in an efficient manner. We constructed a host bacterial cell to link the genotype of REs to the phenotype of β-galactosidase expression based on the bacterial SOS response, and used a high-throughput microfluidic platform to isolate, detect and sort the REs in microfluidic drops at a frequency of ∼800 drops per second. We employed this strategy to screen for the XbaI gene from the constructed libraries of varied sizes. In a single round of sorting, a 90-fold target enrichment was achieved within 1 h. Compared to conventional RE-screening methods, the direct screening approach that we propose excels at efficient search of desirable REs in natural samples – especially unculturable samples – and can be tailored to high-throughput screening of a wide range of genotoxic targets. [ABSTRACT FROM AUTHOR]

Antimicrobial resistance poses a serious threat to human health due to the high morbidity and mortality caused by drug-resistant microbial infections. Therefore, the development of rapid, sensitive and selective identification methods is key to improving the survival rate of patients. In this paper, a sandwich-type electrochemical DNA biosensor based on a polyadenine-DNA tetrahedron probe was constructed. The key experimental conditions were optimized, including the length of polyadenine, the concentration of the polyadenine DNA tetrahedron, the concentration of the signal probe and the hybridization time. At the same time, poly-avidin-HRP80 was used to enhance the electrochemical detection signal. Finally, excellent biosensor performance was achieved, and the detection limit for the synthetic DNA target was as low as 1 fM. In addition, we verified the practicability of the system by analyzing E. coli with the MCR-1 plasmid and realized multi-channel detection of the drug resistance genes MCR-1, blaNDM, blaKPC and blaOXA. With the ideal electrochemical interface, the polyA-based biosensor exhibits excellent stability, which provides powerful technical support for the rapid detection of antibiotic-resistant strains in the field. [ABSTRACT FROM AUTHOR]

A nanocatalytic antimicrobial gel responsive to the bacterial infection microenvironment (IME) possessing highly specific antimicrobial properties provides an opportunity to address the bacterial drug resistance. However, the pH conditions and low substrate concentration in the IME limit the catalytic antimicrobial efficiency of these agents, resulting in unsatisfactory performance. The reported transition metal peroxide alleviates endogenous substrate insufficiency due to H2O2 self-supplying properties, but still suffers from difficulties of simple synthesis, long-stem storage and lower intrinsic catalytic efficiency responsive to the IME. In this paper, we report for the first time the use of cerium-manganese bimetallic peroxide nanoparticles (CeMnOx) as a nanocatalyst with high pH responsiveness, H2O2 self-supplying properties, multiple ROS-generating activity and synergistic effect-enhanced cascade catalytic reactions for efficient antimicrobial therapy. CeMnOx achieved more than 95% kill rate at 50 mg mL-1 for E. coli and 100 mg mL-1 for S. aureus, which was superior to those of previously reported works. To further improve the availability, nanoparticle-carrying hydrogels with excellent antimicrobial properties were prepared through in situ gelation, thus adapting to a wider range of antimicrobial application scenarios. Therefore, the in situ molded nanocatalytic antimicrobial gels provide a promising paradigm for efficient treatment of bacterial infections. [ABSTRACT FROM AUTHOR]

Biological toxicity testing plays an essential role in identifying the possible negative effects induced by substances such as organic pollutants or heavy metals. As an alternative to conventional methods of toxicity detection, paper-based analytical device (PAD) offers advantages in terms of convenience, quick results, environmental friendliness, and cost-effectiveness. However, detecting the toxicity of both organic pollutants and heavy metals is challenging for a PAD. Here, we show the evaluation of biotoxicity testing for chlorophenols (pentachlorophenol, 2,4-dichlorophenol, and 4-chlorophenol) and heavy metals (Cu2+, Zn2+, and Pb2+) by a resazurin-integrated PAD. The results were achieved by observing the colourimetric response of bacteria (Enterococcus faecalis and Escherichia coli) to resazurin reduction on the PAD. The toxicity responses of E. faecalis-PAD and E. coli-PAD to chlorophenols and heavy metals can be read within 10 min and 40 min, respectively. Compared to the traditional growth inhibition experiments for toxicity measuring which takes at least 3 h, the resazurin-integrated PAD can recognize toxicity differences between studied chlorophenols and between studied heavy metals within 40 min. [ABSTRACT FROM AUTHOR]

Plant essential oils have been used for hundreds of years as natural medicines to combat a multitude of pathogens, including bacteria, fungi, and viruses. The paper reports the chemical compositions of essential oil hydrodistilled from the leaves and rhizomes of Amomum unifolium Gagnep. from Vietnam. The main classes of compounds present in the essential oils were monoterpene hydrocarbons (10.1% and 23.9%, respectively), oxygenated monoterpenes (14.5% and 4.9%, respectively), sesquiterpene hydrocarbons (40.9% and 21.9%, respectively), and oxygenated sesquiterpenes (20.1% and 26.8%, respectively). Diterpenes (16.1%) were identified in sizeable proportion in the rhizome essential oil. The constituents occurring in higher amounts in the leaf essential oil were aromadendrene (6.9%), occidenol (6.8%), β-phellandrene (6.2%), β-elemene (5.7%), and δ-elemene (5.0%). However, the main compounds of the rhizome essential oil were β-phellandrene (18.5%), torulosol (16.1%), germacrene D (5.7%), α-cadinol (5.5%) and (6S, 7R)-bisabolene (5.1%). The leaf essential oil of A. unifolium displayed higher antibacterial activity than the rhizome oil. The leaf oil showed activity towards S. aureus ATCC 6538, and B. pumilus ATCC 14884, with MIC values of 75.0 μg/mL and 37.5 μg/mL, respectively. On the other hand, the rhizome essential oil displayed activity against the organisms at MIC value of 150.0 μg/mL. Both essential oils exhibited antibacterial activity to E. coli ATCC 8739, with MIC value of 150.0 μg/mL. The antimicrobial activity of A. unifolium essential oils are being reported for the first time as a confirmation of the ethnomedical uses of A. unifolium in the treatment of diseases especially antimicrobial infections. Furthermore, the paper discusses the chemotaxonomy of Amomum oil samples. [ABSTRACT FROM AUTHOR]

Paper sheets represent one of the infection risk sources inside educational and administrative institutions under biological pandemics. So, the present study aimed to validate the efficiency of gamma radiation or dry heat techniques to sterilize contaminated paper sheets with different indicator pathogens while retaining their structure. The results showed that gamma radiation at 6, 12, or 24 kGy can successfully kill Gram-positive bacteria such as Bacillus cereus and Staphylococcus aureus, Gram-negative bacteria such as Escherichia coli and Salmonella typhi, and fungi such as Candida albicans. Moreover, dry heating at 100 °C for 60 min, 150 °C for 30 min, or 200 °C for 15 min can be successful in paper decontamination of all tested species. Surprisingly, scanning electron microscopy (SEM) micrographs proved that gamma radiation at 6 kGy, dry heat at 100 °C for 60 min or 150 °C for 30 min or 200 °C for 15 min, is suitable for paper sheet sterilization while maintaining their structure. Ultimately, dry heat is a simple, effective, fast, safe, and inexpensive technique for paper sterilization. It may be used as a precautionary step inside educational institutions, especially during written examination periods, to ensure a safe life for academic members during biological pandemics such as COVID-19. [ABSTRACT FROM AUTHOR]

The growing awareness of the importance of bacterial-resistant surfaces has increased since the COVID-19 pandemic global problem. Therefore, the need for antibacterial surfaces has become urgent. The by-product bagasse papers (BPs) were modified with antimicrobial natural rosin, followed by the synthesised graphene oxide and silver nanoparticles (GO-Ag-NPs) through a spin coating approach. The modified samples exhibited a remarkable antibacterial activity towards E. coli (G−ve bacteria) and S. aureus (G+ve bacteria). The microstructure, as well as phase composition of the prepared composites, was identified using various techniques such as Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), and scanning electron microscope (SEM) and hydrophilicity which was metered by water contact angle (WCA). The obtained results demonstrated that the halos of inhibition were noticed for decorated TBP samples by GO-Ag-NPs with various diameters ranging from 20 to 25 mm. Consequently, packaging applications could be extra developed with these renewable nanomaterials. [ABSTRACT FROM AUTHOR]

After an RNA polymerase reaches a terminator, instead of dissociating from the template, it may diffuse along the DNA and recommence RNA synthesis from the previous or a different promoter. Magnetic tweezers were used to monitor such secondary transcription and determine the effects of low forces assisting or opposing translocation, protein roadblocks, and transcription factors. Remarkably, up to 50% of Escherichia coli (E. coli) RNA polymerases diffused along the DNA after termination. Force biased the direction of diffusion (sliding) and the velocity increased rapidly with force up to 0.7 pN and much more slowly thereafter. Sigma factor 70 (σ70) likely remained associated with the DNA promoting sliding and enabling re-initiation from promoters in either orientation. However, deletions of the α-C-terminal domains severely limited the ability of RNAP to turn around between successive rounds of transcription. The addition of elongation factor NusG, which competes with σ70 for binding to RNAP, limited additional rounds of transcription. Surprisingly, sliding RNA polymerases blocked by a DNA-bound lac repressor could slowly re-initiate transcription and were not affected by NusG, suggesting a σ-independent pathway. Low forces effectively biased promoter selection suggesting a prominent role for topological entanglements that affect RNA polymerase translocation. Tiny forces cause E. coli RNA polymerase to slide along DNA after transcription termination at up to 700 bp/s. In this paper, the authors use magnetic tweezers to show that sliding complexes containing complete alpha C-terminal domains repeat transcription from protein roadblocks sites and promoters in either orientation. [ABSTRACT FROM AUTHOR]

The analysis of transcriptional activity of the bacteriophage T5 hol/endo operon conducted in the paper revealed a strong constitutive promoter recognized by E. coli RNA polymerase and a transcription initiation point of the operon. It was also shown that the only translational start codon for holin was a non-canonical TTG. Translation initiation regions (TIRs) of both genes of the operon (hol and endo) were further analyzed using chimeric constructs, in which parts of the hol/endo regulatory regions were fused with the gene of a reporter protein (EGFP). It was found that TIR of hol was 20 times less effective than that of endo. As it turned out, the level of EGFP production was influenced by the composition of the constructs and the type of the hol start codon. Apparently, the translational suppression of holin's accumulation and posttranslational activation of endolysin by Ca2+ are the main factors ensuring the proper timing of the host cell lysis by bacteriophage T5. The approach based on the use of chimeric constructs proposed in the paper can be recommended for studying other native or artificial operons of any complexity: analyzing the impacts of separate DNA regions, as well as their coupled effect, on the processes of transcription and translation of recombinant protein(s). [ABSTRACT FROM AUTHOR]