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Purpose: To analyze the effectiveness of coating of abutments with antimicrobial agents and their influence on the physicochemical and biologic properties of the coated materials. Materials and Methods: This work was registered in Open Science Framework (osf.io/6tkcp) and followed the PRISMA protocols. A search of two independent reviewers of articles published up to October 29, 2021, was performed in the Embase, PubMed, Science Direct, and Scopus databases. Results: The databases found a total of 1,474 references. After excluding the duplicates, 1,050 remained. After reading the titles and abstracts and applying the inclusion criteria, 13 articles remained and were read in full. A total of 8 articles were included in this systematic review. Different antimicrobial agents have been used to coat abutments, including graphene oxide, polydopamine, titanium and zirconium nitride, lactoferrin, tetracycline, silver, and doxycycline with varied release times. Titanium-coated silver showed a better antimicrobial agent release time of up to 28 days. Chemical analysis confirmed the presence of antimicrobials on the surface after coating. Different pathogenic microorganisms, such as Streptococcus sanguinis, Streptococcus oralis, and Staphylococcus aureus, were inhibited when in contact with the coated surface. Conclusions: This review showed that there is still no consensus on which is the better antimicrobial agent and which coated materials have the better performance. However, the association of surface coating of abutments with antimicrobials is feasible and can benefit many patients, which can support their clinical use to favor the healing process and prevent infections that can lead to treatment failure with dental implants. [ABSTRACT FROM AUTHOR]

BACKGROUND: The obligate intracellular bacterial family Chlamydiaceae comprises a number of different species that cause disease in various vertebrate hosts including humans. Chlamydia suis, primarily found in the gastrointestinal tract of pigs, is the only species of the Chlamydiaceae family to have naturally gained tetracycline resistance (TetR), through a genomic island (Tet-island), integrated into the middle of chromosomal invasin-like gene inv. Previous studies have hypothesised that the uptake of the Tet-island from a host outside the Chlamydiaceae family was a unique event, followed by spread among C. suis through homologous recombination. In vitro recombination studies have shown that Tet-island exchange between C. suis strains is possible. Our aim in this study was to gain a deeper understanding of the interclade recombination of the Tet-island, among currently circulating C. suis field strains compared to in vitro-generated recombinants, using published whole genome sequences of C. suis field strains (n = 35) and in vitro-generated recombinants (n = 63). RESULTS: We found that the phylogeny of inv better reflected the phylogeny of the Tet-island than that of the whole genome, supporting recombination rather than site-specific insertion as the means of transfer. There were considerable differences between the distribution of recombinations within in vitro-generated strains compared to that within the field strains. These differences are likely because in vitro-generated recombinants were selected for a tetracycline and rifamycin/rifampicin resistant background, leading to the largest peak of recombination across the Tet-island. Finally, we found that interclade recombinations across the Tet-island were more variable in length downstream of the Tet-island than upstream. CONCLUSIONS: Our study supports the hypothesis that the occurrence of TetR strains in both clades of C. suis came about through interclade recombination after a single ancestral horizontal gene transfer event.

Author(s): Atreyo Chakraborty [1] Introduction[sup.[1]] Pre- and post-exposure prophylaxis has been gaining interest in the recent decade for the prevention of various sexually transmitted diseases. This is partly fuelled by [...]

Bovine respiratory disease (BRD) is the leading cause of mortality and antimicrobial drug (AMD) use in weaned dairy heifers. Limited information is available regarding antimicrobial resistance (AMR) in respiratory bacteria in this population. This study determined AMR gene presence in 326 respiratory isolates (Pasteurella multocida, Mannheimia haemolytica, and Histophilus somni) from weaned dairy heifers using whole genome sequencing. Concordance between AMR genotype and phenotype was determined. Twenty-six AMR genes for 8 broad classes of AMD were identified. The most prevalent, medically important AMD classes used in calf rearing, to which these genes predict AMR among study isolates were tetracycline (95%), aminoglycoside (94%), sulfonamide (94%), beta-lactam (77%), phenicol (50%), and macrolide (44%). The co-occurrence of AMR genes within an isolate was common; the largest cluster of gene co-occurrence encodes AMR to phenicol, macrolide, elfamycin, β-lactam (cephalosporin, penam cephamycin), aminoglycoside, tetracycline, and sulfonamide class AMD. Concordance between genotype and phenotype varied (Matthews Correlation Coefficient ranged from -0.57 to 1) by bacterial species, gene, and AMD tested, and was particularly poor for fluoroquinolones (no AMR genes detected) and ceftiofur (no phenotypic AMR classified while AMR genes present). These findings suggest a high genetic potential for AMR in weaned dairy heifers; preventing BRD and decreasing AMD reliance may be important in this population.

Genetic screening of pools of mutants can reveal genetic determinants involved in complex biological interactions, processes, and systems. We previously constructed two single-gene deletion resources for Salmonella enterica serovar Typhimurium 14028s in which kanamycin (KanR) and chloramphenicol (CamR) cassettes were used to replace non-essential genes. We have now used lambda-red recombination to convert the antibiotic cassettes in these resources into a tetracycline-resistant (TetR) version where each mutant contains a different 21-base barcode flanked by Illumina Read1 and Read2 primer sequences. A motility assay of a pool of the entire library, followed by a single-tube processing of the bacterial pellet, PCR, and sequencing, was used to verify the performance of the barcoded TetR collection. The new resource is useful for experiments with defined subsets of barcoded mutant strains where biological bottlenecks preclude high numbers of founder bacteria, such as in animal infections. The TetR version of the library will also facilitate the construction of triple mutants by transduction. The resource of 6197 mutants covering 3490 genes is deposited at Biological and Emerging Infections Resources (beiresources.org).

BACKGROUND: Comprehensive descriptions of equids with granulocytic anaplasmosis (EGA) with neurologic or muscle disease and other atypical presentations are scarce in the literature. OBJECTIVE: Describe the clinical signs, laboratory findings, treatment, and outcome of equids with EGA with emphasis on neurologic and muscle disease. ANIMALS: Thirty-eight horses, 1 donkey. METHODS: Retrospective study. Equids with EGA were included. The electronic data base was searched from January 2000 to December 2022 using the words anaplasmosis, ehrlichiosis, granulocytic, and rickettsia. Signalment and clinical data were reviewed. Data were evaluated for normality using Shapiro-Wilk test. Parametric and nonparametric statistics were used for normally and non-normally distributed data. RESULTS: Common (41%) and other (59%) presentations were seen in horses ≥ 4 years of age (median, 14 years) with an overrepresentation of males (77%). Neurologic disease was common (41%), mainly presenting as diffuse symmetrical proprioceptive ataxia. Brain disease was less common manifesting as obtundation and cranial nerve deficits. Muscle disease was less common, with QH breeds with the variant causing myosin heavy chain myopathy (MYHM) having severe disease. Cavitary effusion, cardiomyopathy and disseminated intravascular coagulation (DIC) were uncommon. Clinical laboratory results varied depending on disease stage. Muscle enzyme activities were significantly higher in horses with muscle disease. Outcome was favorable with prompt tetracycline treatment. Death and long-term sequelae were not reported. CONCLUSIONS AND CLINICAL IMPORTANCE: Common and atypical presentations of EGA have a favorable outcome with prompt tetracycline treatment. Quarter horse breeds with muscle disease should be genotyped for MYHM.

This study investigated the prevalence and antimicrobial resistance (AMR) of Escherichia coli (E. coli) in Nile tilapia from fresh markets and supermarkets. A total of samples (n = 828) were collected from Nile tilapia including fish flesh (n = 276), liver and kidney (n = 276), and intestine (n = 276). Overall prevalence of fecal coliforms (61.6%) and E. coli (53.0%) were observed. High prevalence of E. coli was found in the intestine (71.4%), followed by the liver and kidney (45.7%). The highest prevalence of resistance was commonly found against tetracycline (78.5%), ampicillin (72.8%), and sulfamethoxazole (45.6%) with resistance to only tetracycline (15.2%) as the most common antibiogram. The prevalence of multidrug resistance (MDR) (54.4%) and Extended-spectrum beta-lactamases (ESBLs) (5.7%) were examined. The predominant virulence genes (n = 158) were st (14.6%), followed by eaeA (0.6%). The blaTEM (73.4%), tetA (65.2%), and qnrS (57.6%). There is statistical significance between Nile tilapia from fresh markets and supermarkets. Based on logistic regression analysis, ampicillin-resistant E. coli was statistically associated with the phenotypic resistance to tetracycline and trimethoprim, and the presence of blaTEM and tetA (p < 0.05). Further investigation of AMR transference and their mechanisms is needed for AMR control.

Oxygen (O2) electroreduction offers a green approach for singlet oxygen (1O2) synthesis in wastewater contaminants detoxification. However, traditional single O2 activation on single‐metal catalytic sites seriously suffers from the kinetically‐unfavorable desorption of adsorbed superoxide species (•O2−*/•OOH*). Here, we demonstrate a novel dual O2 coactivation pathway on shortened Fe1−OV−Ti sites for superior 1O2 electrosynthesis through a rapid disproportionate process between surface‐confined •O2−*/•OOH*. Theoretical calculations combined with in situ electrochemical spectroscopies demonstrated that the shortened distance between Fe single atom and adjacent unsaturated Ti atom facilitates the direct recombination of surface‐confined Fe−•OOH and Ti−•OO− to yield 1O2, bypassing the formidable •O2−*/•OOH* desorption process. Impressively, Fe1−OV−Ti could realize an excellent 1O2 electrosynthesis rate of 54.5 μmol L−1 min−1 with an outstanding 1O2 selectivity of 97.6 % under neutral condition, surpassing that of Fe1−O−Ti (27.1 μmol L−1 min−1, 91.7 %). Using tetracycline (TC) as a model pollutant, the resulting Fe1−OV−Ti electrode achieved nearly 100 % degradation in 120 min at −0.6 V, meanwhile preventing the generation of toxic intermediates. This study provides a new 1O2 electrosynthesis strategy by controlling the distance of adjacent catalytic sites for the coactivation of dual molecular oxygen. [ABSTRACT FROM AUTHOR]

In the present research, it is reported that ball milling technique can be applied to enhance the photocatalytic properties of MnO and ZrO 2 metal oxide powders (MZOx) furthermore the fabricated photocatalyst can be used for the degradation of tetracycline (TTC). XRD analyses revealed that increasing the milling time resulted in the formation of a pure metallic Mn crystal phase, which boosted the antibiotic degradation rate. It was confirmed by SEM technique that the morphological structures of the particles were generally small and uniform. The band gap energy was calculated as 3.70 eV for the hybrid metal oxide. Additionally, the adsorptive and photoluminescence features were illuminated via DRS and PL analyses. The effect of milling time had a major impact on the photodegradation rate of TTC, and the 8 h milling sample (MZOx-8h) exhibited the highest catalytic degradation activity (79.4 %). Low photocatalytic activity was obtained at acidic pHs and increased at alkaline pHs. The presence of H 2 O 2 sharply decreased photocatalytic process time (60 min) and 94.3 % of the TTC was degraded at 7.5 mM H 2 O 2. The photocatalytic degradation process proceeded through superoxide radicals and was supported by holes. The stability of MZOx-8h almost remained constant (70.02 %) even after seven cycles. It was determined that the presence of oxalic acid positively affected the progress of TTC degradation reactions. Further, practical application areas were investigated and MZOx-8h doped on support materials was found to be suitable for such applications in proportion to the doping ratio. Finally, it was demonstrated that MZOx-8h exhibited remarkable performance in photocatalytic reactions of different types of organic pollutants. The synergistic nature of MnO and ZrO 2 with the contribution of ball milling time effect resulted in high photocatalytic activity. • High purity metallic Mn phase was successfully synthesized by ball-milling. • MZOx was used for the first time in TTC photodegradation. • TTC degradation was stable in the seventh cycle. • The different organic pollutants were removed with high efficiency. [ABSTRACT FROM AUTHOR]

In this study, a ratiometric fluorescent sensor CdTe QDs@ZIF-8 with butterfly spectra is successfully constructed by in situ encapsulating mercaptopropionic acid-modified CdTe quantum dots in zeolitic imidazolate framework-8 (ZIF-8) with a simple strategy, and used for the detection of tetracycline in fluorescence/smartphone colorimetry dual-mode. ZIF-8 not only reduces the agglomeration of the quantum dots but also surprisingly generates a new green fluorescence signal at 524 nm while the red fluorescence of the CdTe quantum dots at 650 nm quenches when tetracycline is added. The two opposing fluorescence signals create a butterfly-shaped fluorescence spectrum, allowing the sensor to detect tetracycline over a linear range of 0–70 μM with the detection limit (LOD) of 0.0155 μM by using a ratiometric fluorescence technique. What is more, based on the obvious color change of the fluorescent sensor gradually from red to green under UV light, a highly stable point-of-care testing sensor has been developed for on-site detection of tetracycline through color recognition by smartphones, which can be used for real-time detection of this antibiotic in the range of 0–1000 μM with the LOD of 0.0249 μM. This work provides a simple and efficient method for the on-site detection of tetracycline. [ABSTRACT FROM AUTHOR]

The current study investigates removing tetracycline from water using batch, column, and tank experiments with statistical modelling using ANN for continuous tests. An artificial neural network (ANN) using the Levenberg-Marquardt back-propagation (LMA) training algorithm is constructed to compare the effectiveness of Tetracycline removal from aqueous solution using the sorption technique with prepared adsorbent. Several characterization analyses XRD, FT-IR, and SEM are employed for prepared Brownmillerite (Ca2Fe2O5)–Na alginate beads. The operating conditions of batch tests involved, contact time (0.1–3 h), initial of tetracycline (Co) of (100–250 mg/L), pH (3–12), agitation speed (50–250) rpm and dosage of adsorbent (0.2–1.2 g/50 mL). The outcomes of experiments have demonstrated that the optimum conditions for the batch test to achieve the maximum adsorbent capacity (qmax =7.845 mg/g) are achieved at pH 7, contact time 1.5 h, adsorbent dose 1.2 g/50 mL, agitation speed of 200 rpm, and initial concentration of TC 100 mg/L. Minimum mean square error (MSE) values of 7.09E-04 for 30 hidden neurons and 0.0029 for 59 hidden neurons in the 1D and 2D systems are accomplished, respectively. The artificial neural network model has exhibited excellent performance with correlation coefficients exceeding 0.980 for the operating variables, demonstrating its accuracy and effectiveness in predicting the experimental outcomes. According to sensitivity analysis, the influential parameter in the column test (1D) is the flow rate (mL/min), with a relative importance of 32.769%. However, in the tank test (2D), time (day) is signified as an influential parameter with a relative importance of 31.207%. [ABSTRACT FROM AUTHOR]

Purpose: Since decades, numerous antibiotics have been used to treat different bacterial illnesses; among these, tetracycline is one of the commonly used antibiotics, which has led to development of bacterial resistance. To tackle this critical issue, we have developed a novel, biocompatible nanodrug that improves the antibacterial activity of tetracycline by conjugating it with copper oxide nanoparticles, thereby addressing the problem of multidrug resistance in bacteria. Methods: In this study, using unipot approach, tetracycline conjugated copper oxide nanoparticles were synthesized where tetracycline act as reducing as well as stabilizing agent. These nanoparticles were characterized by different analytical and microscopic technique. For statistical analysis, FFD and CCD model were employed to assess the effect of various parameters (concentration, pH, temperature and time). Results: The synthesis of nanoparticles was confirmed through different techniques. Synthesized nanoparticles exhibited the highest antibacterial activity against various microbes including multi‐drug resistant microbes compared to its individual constituents. DPPH and ABTS assays revealed high antioxidant activity of nanoparticles whereas, biocompatibility was assessed via MTT assay. The drug release profile confirms the sustained release of tetracycline molecules. Conclusions: We have successfully developed tetracycline conjugated copper oxide nanoparticles exhibiting potent antibacterial, antioxidant and biocompatible activity. [ABSTRACT FROM AUTHOR]

This study developed a dual-readout system utilizing fluorescence and colorimetry based on iron oxide quantum dots (IO-QDs) for detecting tetracycline (TCy). IO-QDs were synthesized within 6 h using L-leucine as a surface modifier, achieving a more efficient route. Upon interaction with TCy, IO-QDs exhibited a significant decrease in fluorescence response and observable color changes, while fluorescence lifetime remained consistent regardless of TCy presence. Moreover, IO-QDs' fluorescence response remained stable across various temperatures. The Förster resonance energy transfer distance of less than 2 nm and a quenching constant of 2.90 × 1012 M–1s–1 indicated static quenching in the presence of TCy. Additionally, significant changes in observed and corrected fluorescence efficiency suggested the involvement of the inner filter effect in the fluorescence quenching of IO-QDs. The synthesized IO-QDs were then utilized for selective and rapid fluorescence-based TCy detection, showing a linear range of 0.5 to 80 μM. Simultaneously, a colorimetric method for TCy detection was established, demonstrating a good linear relationship within the range of 0.5 to 20 μM. The detection limits for TCy were determined as 0.539 and 0.329 μM using fluorescence and colorimetric approaches, respectively. Furthermore, IO-QDs were applied to detect real samples, and the dual-readout probe exhibited satisfactory recoveries, confirming the practical reliability of the developed method for analyzing milk and drinking water samples. [ABSTRACT FROM AUTHOR]

Antibiotic residues have become a significant challenge in food safety, threatening both ecosystem integrity and human health. To combat this problem, we developed an innovative photo‐powered, self‐powered aptasensor that employs a novel carbon‐doped three‐dimensional graphitic carbon nitride (3D‐CN) combined with a metal‐organic framework composed of N‐doped copper(I) oxide‐carbon (Cu2O@C) skeletons. The 3D‐CN serves as the photoanode, offering stable photocurrent production due to its three‐dimensional open framework structure. The N‐doped Cu2O@C acts as the photocathode, providing oxidation protection for the metal core and enhancing light absorption due to its metal‐organic framework structure. A key feature of our work is exploiting the Fermi level difference between the n‐type photoanode and p‐type photocathode, which facilitates faster migration of photogenerated electrons toward the photocathode, thereby enhancing the sensor's self‐powered effect. Experimental results reveal that upon aptamer loading, the sensor can linearly detect tetracycline (TC) within a range of 0.5 pmol/L to 300 nmol/L, with a detection limit as low as 0.13 pmol/L. It also demonstrates excellent selectivity, stability, and reproducibility, making it applicable to real samples such as milk and river water. Consequently, our research provides a highly efficient and sensitive method for monitoring TC in food, with significant practical implications and profound impacts on food safety. [ABSTRACT FROM AUTHOR]

Objectives We performed a retrospective analysis of MRSA isolates collected at the university equine clinic including clinical isolates from 2008 to 2021 and screening environmental, equine and personnel isolates from 2016. Methods Screening and clinical samples were cultured on Brilliance MRSA 2 and Columbia agar (Oxoid), respectively, with enrichment for environmental samples. Antimicrobial susceptibility was assessed by disc diffusion. All the isolates were characterized by spa typing. Eighteen selected isolates were subjected to WGS with subsequent wgMLST clonal analysis. Results Among 75 MRSA isolates, five spa types were identified, the majority (n  = 67; 89.33%) was t011. All isolates were resistant to cefoxitin and ampicillin and carried the mecA gene. In addition, the isolates were resistant to tetracycline (n  = 74; 98.67%), gentamicin (n  = 70; 93.33%), enrofloxacin (n  = 54; 72.00%), sulfamethoxazole-trimethoprim (n  = 5; 6.67%) and lincomycin (n  = 3; 4.00%) with corresponding genetic markers for the resistance detected in the sequenced isolates. All 18 sequenced isolates belonged to ST398, 16 carried SCC mec type IVa and two carried SCC mec type Vc (5C2&5). Further, isolates carried aur , hlgA , hlgB and hlgC virulence genes, and five isolates carried sak and scn genes, which are part of the immune evasion cluster. Close genetic relatedness was found between isolates from the staff of the clinic and clinical samples of horses. Conclusions Repeated introduction and long-term persistence of the equine LA-MRSA subclone (ST398-MRSA-IVa/Vc(5C2&5), t011) among the infected horses at the equine clinic with the colonization of personnel, and the environment contamination that might contribute to transmission were observed. [ABSTRACT FROM AUTHOR]

The widespread use of antibiotics in intensive animal husbandry, and the agricultural utilization of manure from such farms, imposes a significant burden on the environment. Consequently, the effects of antibiotics should be studied not only in animals and humans but also in all components of biocenoses and agrocenoses. In our study, we analyze the impact of four different concentrations of tetracycline present in soil (0, 5, 50, and 500 mg/kg of soil) on the growth and key photosynthesis parameters of pea seedlings: chlorophyll concentration, aminolevulinic acid concentration, aminolevulinic acid dehydrogenase activity, and ribulose bisphosphate carboxylase-oxygenase (RuBisCO) activity. At the lowest tetracycline concentration, chlorophyll content decreased by 13% compared to the control (0 tetracycline), while at the highest antibiotic concentration, it decreased by as much as 27%. Similarly, the decrease in aminolevulinic acid (a chlorophyll precursor) concentration was significant, amounting to 34%. However, the activity of the dehydrogenase enzyme, which consumes this precursor, decreased even more drastically by 51%, indicating significant disturbances in the light phase of photosynthesis. However, the activity of RuBisCO in pea plants subjected to tetracycline was even more severely affected, dropping by 58%, 69%, and 70% in soils with increasing concentrations of tetracycline. The reduction in enzyme activity could only partially be explained by a less pronounced decrease in the quantity of RuBisCO (large subunit) protein, which amounted to 6.5%, 11%, and 35% for tetracycline concentrations of 5, 50, and 500 mg/kg of soil, respectively. [ABSTRACT FROM AUTHOR]

Ce-doped WO3 nanoparticles were fabricated and characterized using powder X-ray diffraction (XRD), Fourier-transform infrared (FTIR), Raman, SEM–EDX, UV–Vis, photoluminescence (PL), dynamic light scattering (DLS), and X-ray photoelectron spectroscopy (XPS) analyses. The results revealed the formation of a highly crystalline monoclinic phase in Ce-doped WO3 photocatalyst (abbreviated WCC), confirmed by Raman spectroscopy. The bandgap was tuned by increasing the percentage of Ce dopant, where the WCC (1 mol wt% Ce-doped WO3) photocatalyst sample exhibited the highest photocatalytic activity towards synthetic methylene blue (MB) dye pollutant and biodegradation-resistant tetracycline hydrochloride (TC-HCl) antibiotic. The decomposition efficiency using the WCC photocatalyst against aqueous MB dye and TC-HCl antibiotic reached 95% and 51% after exposure to simulated sunlight irradiation for 180 min, with excellent stability after four recycling runs. The interfacial contact between Ce and WO3 effectively shortened the charge transfer carrier process, enabling redox reactions to provide the best decomposition efficiency over the investigated pollutants. The photodecomposition rate constant of WCC was 0.017 min−1 for MB dye, which is 3.6-fold higher performance than common literature photocatalysts. The results showed the significance of the environmental impact toxicity assessment by applying the treated water to finger millet plant growth. Based on the research feasibility, the synthesized photocatalyst demonstrated superior decomposition against dyes and antibiotics, making it highly suitable for applications in wastewater treatment. Moreover, the use of degraded water resulted in productive plant growth. [ABSTRACT FROM AUTHOR]

Addressing the challenges posed by the high cost and limited efficiency of traditional Chinese medicine wastewater treatment, the development of a cost-effective and highly efficient catalyst for activating persulfate (PMS) to degrade organic pollutants holds significant practical importance. This research successfully synthesized a zinc-cobalt bimetallic catalyst supported on sepiolite (Zn-Co@SEP). The verification was performed using various characterization techniques, including Scanning Electron Microscopy (SEM), X-ray Diffraction (XRD), Fourier Transform Infrared Spectroscopy (FT-IR), and X-ray Photoelectron Spectroscopy (XPS). XRD and SEM results both indicate that Zn-Co@SEP has excellent crystallinity, with active metal particles uniformly distributed on the surface of sepiolite nanofibers and consistent particle size. Additionally, the BET method determined the specific surface area of Zn-Co@SEP to be 5.533 m2/g. The introduction of sepiolite as a carrier provided additional active sites, facilitating the redox cycling of Co2+/Co3+ and Zn2+/Zn3+, which continuously generated reactive species. Zn-Co@SEP exhibited remarkable catalytic activity towards PMS, achieving a degradation efficiency of over 93% for TC (50 mg/L) within just 30 min in the Zn-Co@SEP/PMS system. The study systematically investigated the influence of Zn-Co@SEP dosage, PMS dosage, TC concentration, pH, and temperature on the degradation efficiency of the catalytic system. Notably, the Zn-Co@SEP/PMS system maintained high degradation rates for TC across a wide pH range (3–11) and demonstrated robust stability and recyclability, retaining a degradation rate of 89.56% after four cycles of reuse. Further experimental evidence from free radical quenching studies, electron paramagnetic resonance (EPR) experiments, and oxidative capacity potential (OCPT) results underscored the involvement of multiple radicals (1O2, SO4−•, O2−•, •OH) and electron transfer pathways in promoting TC degradation. In conclusion, this research contributes new insights into the synthesis of efficient PMS catalysts tailored for the degradation of antibiotic wastewater, addressing a critical need in environmental remediation. [ABSTRACT FROM AUTHOR]

A photocatalysis system is widely regarded as the most renewable approach to environmental treatment since sunlight is a long-term source of energy for the planet. This study assessed the efficacy of a photocatalyst graphitic carbon nitride/bismuth oxychloride (g-C3N4/BiOCl) by using scanning electron microscopy (SEM), ultraviolet-visible diffuse reflectance spectroscopy (DRS), photo-luminance, photocurrent density, and X-ray diffraction to characterize the photocatalyst. The results showed an improvement in morphology and enhanced photodegradation of pharmaceutical residues such as Nitenpyram, Tetracycline, and Rhodamine B. For a wavelength range of 655 to 420 nm, the synthesized photocatalysts were good at the absorption of visible light. A photodegradation proficiency of 64.72% was observed with tetracycline, 48.91% nitenpyram, and 98.70% with Rhodamine B in 30 min. The g-C3N4/BiOCl displayed a significant photocatalytic activity due to high load separation and transition. This study shows that g-C3N4/BiOCl photocatalyst has been confirmed as one of the most intriguing contenders for innovative photocatalyst designs and can potentially be used in treating wastewater and the environment at large. [ABSTRACT FROM AUTHOR]

CoNOC with CoN (Pd)3 N (Po)1 O1 structure can efficiently catalyse the electro-Fenton reaction to generate –OH to degrade antibiotic pollutants represented by tetracyclines. [Display omitted] • Oxygen-doped Co SACs were prepared using a temperature gradient pyrolysis strategy with nitric acid oxidation method. • DFT calculations explained the excellent catalytic performance was due to the electronic modulation of Co sites by the O doping and N coordination. • TC degradation of 95 % in 120 min and mineralization efficiency of almost 90 % in 180 min were achieved in the electro-Fenton system. • The significant involvement of OH was confirmed, and the degradation pathways of TC have been analyzed and predicted. Electro-Fenton is an effective process for degrading hard-to-degrade organic pollutants, such as tetracycline (TC). However, the degradation efficiency of this process is limited by the activity and stability of the cathode catalyst. Herein, a temperature gradient pyrolysis strategy and oxidation treatment is proposed to modulate the coordination environment to prepare oxygen-doped cobalt monoatomic electrocatalysts (CoNOC). The CoNOC catalysts can achieve the selectivity of 93 % for H 2 O 2 with an electron transfer number close to 2. In the H-cell, the prepared electrocatalysts can achieve more than 100 h of H 2 O 2 production with good stability and the yield of 1.41 mol g catalyst −1 h−1 with an average Faraday efficiency (FE) of more than 88 %. The calculations indicate that the epoxy groups play a crucial role in modulating the oxygen reduction pathway. The O doping and unique N coordination of Co single-atom active sites (CoN (Pd)3 N (Po)1 O1) can effectively weaken the O 2 /OOH* interaction, thereby promoting the production of H 2 O 2. Finally, the electro-Fenton system could achieve a TC degradation rate of 94.9 % for 120 min with a mineralization efficiency of 87.8 % for 180 min, which provides a reliable option for antibiotic treatment. The significant involvement of OH in the electro-Fenton process was confirmed, and the plausible mineralization pathway for TC was proposed. [ABSTRACT FROM AUTHOR]

[Display omitted] The activation of peroxymonosulfate (PMS) by carbon-based catalysts is deemed to be a promising method for the degradation of refractory organic contaminants in wastewater. Herein, a Cu-doping strategy in B and N co-doped carbon nanotubes with highly dispersed B O Cu sites and graphite nitrogen were successfully synthesized for activating PMS to degradate tetracycline. The best removal rate of tetracycline within 60 min (97.63 %) was obtained by the 1.5 % Cu-BNC and the degradation rate was increased by 17.9 times. The enhanced catalyst activity was attributed to the promoting the cycle of the Cu(I)/Cu(II) redox pair by the formed B O Cu sites, and the accelerating the electron transfer process by the adsorption of graphitic N for PMS. The non-free radical pathway including 1O 2 and electron transfer played a dominant role in the 1.5 % Cu-BNC/PMS system. The degradation intermediates of TC were identified and three possible degradation pathways were proposed. Further toxicity analysis of the intermediates showed that the 1.5 % Cu-BNC/PMS system had a significant effect on weakening and reducing the biological toxicity and mutagenicity of TC. Moreover, it presented an excellent degradation performance in raw natural water. In general, the proposed regulation of carbon-based catalysts via the coordination-driven effect provides ideas for efficient wastewater treatment. [ABSTRACT FROM AUTHOR]

A novel organic-inorganic photocatalyst like layer structured graphitic carbon nitride (g-C3N4 or CN) hybrid with strontium titanate (SrTiO3 or STO) was prepared by a precipitation-sonication technique for photocatalytic activity. The crystal phases, morphologies, elemental composition, optical properties, and porous structure of the prepared pristine and STO/CN hybrid composite were measured using various physicochemical characterizations. It is indicated that STO nanospheres were effectively loaded on the g-C3N4 nanosheets, resulting in the STO/CN hybrid composite, high surface area, enhanced visible-light absorption, enhancing photoinduced charge separation and suppressing the recombination rate. Furthermore, the 3 wt% of g-C3N4 composited STO (STO/CN-3) catalyst demonstrated higher photocatalytic activity than pristine STO in 100 min under white light irradiation, reaching the degradation efficiency of 92.66 % and 93.31 % toward methylene blue (MB) and tetracycline (TC), respectively. The improved photocatalytic activity of STO/gCN hybrid composite could be ascribed to the synergistic effect between STO and CN with strong interfacial interaction facilitating efficient charge separation and inhibiting the charge recombination of photogenerated electron-hole pairs. Moreover, a possible photocatalytic mechanism has been proposed for the degradation of MB and TC. Besides, the excellent photocatalytic performance, STO/CN-3 nanocomposite also exhibits outstanding photostability under the current factors, suggesting that they are suitable for practical applications. [ABSTRACT FROM AUTHOR]

Tetracycline (TC), a widely used antibiotic, can easily enter aquatic ecosystems through soil erosion, livestock manures, and wastewater discharge, causes environmental and ecological health effects. AgCuFe2O4@Methylcellulose (MC)/Activated Carbon (AC) magnetic nanocomposite was synthesized accompanied by microwave-assisted co-precipitation procedure under green circumstances with high efficiency and subsequently utilized as a new heterogeneous magnetic nano-photocatalyst in the TC photodegradation from aqueous solutions. The structural characterization of AgCuFe2O4@MC/AC was performed by various analytical techniques. Afterwards, the key parameters of the photocatalytic TC degradation process, such as catalyst dose, TC concentration, pH, and process time, were investigated and optimized the results showed that the catalyst was synthesized on a nanometer scale (25 nm) with a quasi-spherical structure, with a high specific surface area, high magnetic strength (Ms = 19.27 emu g−1), and the preservation of the crystal structure. The removal efficiency of TC under optimal conditions including pH 7, initial TC concentration of 5 mg L−1, nano-photocatalyst dose of 0.5 g L−1, 90 min of irradiation time was reported to be 90.91% for synthetic sample and 87.17% for real wastewater sample. The removal effectiveness of total organic carbon was 85.2% under optimal conditions. The photocatalytic degradation kinetics of TC followed pseudo-first-order and Langmuir–Hinshelwood kinetic models, with values of KL–H = 0.633 L mg−1 and Kc = 0.126 mg L−1 min−1. After four cycles of recovery and regeneration, the synthesized catalyst demonstrated high chemical stability and was able to remove 62% of the pollutant. Finally, this study provides a viable approach for removing antibiotics using an AgCuFe2O4@MC/AC-based heterogeneous nanostructured photocatalyst. [ABSTRACT FROM AUTHOR]

Tetracycline antibiotics are a common type of antibiotics in life. In this research, Fe2+ and Cu2+ was used to modify granular activated carbon, and peroxydisulfate was activated under the synergistic action of electrochemistry (EC/Fe-Cu-GAC/PS). The effects of the initial concentration of tetracycline hydrochloride (TCH), initial pH, current density, and plate spacing on the degradation of TCH were investigated. Experimental results indicated that the removal efficiency of TCH was 87.27% by the EC/Fe-Cu-GAC/PS system. The removal rate of TCH decreased with the increase of initial concentration of TCH. The TCH removal rate is maintained at a high level when pH values range from 3 to 7. Increasing the amount of catalyst and persulfate in a certain range, as well as the magnitude of current density and plate spacing are helpful for TCH removal. When the initial TCH concentration is 20 mg/L, the initial pH value is 5.0, the amount of Fe-Cu-GAC is 2.0 g, the PS concentration is 2 mmol/L, the electrolyte concentration is 25 mmol/L, the current density is 15 mA/cm2, and the plate spacing is 9 cm, the TCH removal effect is the most effective. The free-radical experiment showed that sulfate radicals (SO4•−) played a dominant role under acidic conditions. According to the data analysis, the kinetic model of the EC/Fe-Cu-GAC/PS system was consistent with the first-order reaction kinetics. According to the reaction dynamics, we get the rating of influencing factors that influence the effect of TCH removal. The EC/Fe-Cu-GAC/PS system can effectively degrade tetracycline antibiotics in water. [ABSTRACT FROM AUTHOR]

Traditional light‐driven metal‐organic‐frameworks (MOFs)‐based micromotors (MOFtors) are typically constrained to two‐dimensional (2D) motion under ultraviolet or near‐infrared light and often demonstrate instability and susceptibility to ions in high‐saline environments. This limitation is particularly relevant to employing micromotors in water purification, as real wastewater is frequently coupled with high salinity. In response to these challenges, ultrastable MOFtors capable of three‐dimensional (3D) motion under a broad spectrum of light through thermophoresis and electrophoresis are successfully synthesized. The MOFtors integrated photocatalytic porphyrin MOFs (PCN‐224) with a photothermal component made of polypyrrole (PPy) by three distinct methodologies, resulting in micromotors with different motion behavior and catalytic performance. Impressively, the optimized MOFtors display exceptional maximum velocity of 1305 ± 327 µm s−1 under blue light and 2357 ± 453 µm s−1 under UV light. In harsh saline environments, these MOFtors are not only maintain high motility but also exhibit superior tetracycline hydrochloride (TCH) removal efficiency of 3578 ± 510 mg g−1, coupling with sulfate radical‐based advanced oxidation processes and peroxymonosulfate. This research underscores the significant potential of highly efficient MOFtors with robust photocatalytic activity in effectively removing TCH in challenging saline conditions, representing a substantial advancement in applying MOFtors within real‐world water treatment technologies. [ABSTRACT FROM AUTHOR]

Heterogeneous cobalt‐based catalysts are highly effective in activing peroxymonosulfate (PMS) and produce free radicals to deal with recalcitrant organic pollutants in water. However, unfeasible recyclability and gradual performance degradation remain challenging due to the easy agglomeration and leaching of active cobalt species. Herein, a strategy is proposed to construct stably anchored and highly dispersed Co2+ sites on dual functional sulfonated covalent organic frameworks (COF‐Co). The sulfonic acid groups are able to realize the targeted binding with cobalt ions through a two‐step cation‐exchange method, leading to strong combination with active Co2+ sites and utmost utilization efficiencies. Moreover, the super‐hydrophility of sulfonic acid groups favors the rapid accessibility of organic molecules to the catalyst and accelerates the degradation. Remarkably, COF‐Co exhibits high activity in PMS activation, effective oxidation for tetracycline degradation (92% within 30 min at 30 mg L−1) and other coloring contaminants, and excellent recycle stability. This work can guide the rational design of efficient and environmentally friendly PMS‐activated catalyst with great potential for application in wastewater treatment. [ABSTRACT FROM AUTHOR]

Pharmaceutical pollutants introduce highly intricate compounds into the environment due to extensive structural and functional alterations resulting in adverse health effects on organisms. Herein, a novel nanocomposite is designed comprising Cu‐doped BiOBr nanoflakes and g‐C3N4 to form a dual absorber based on the organic‐inorganic electronic interface for photocatalytic degradation of tetracycline (TC). With incorporating Cu in BiOBr and compositing with g‐C3N4, the band gap decreased from 2.74 eV to 2.36 eV for BiOBr:Cu/g‐C3N4, and also light harvesting ability increased. The investigation into the degradation rate considered factors such as pH, TC concentration, photocatalyst dosage, and irradiation time, resulting in a TC degradation efficiency of 98 % within 60 min. In the prepared nanocomposite, photo‐generated electrons of BiOBr can recombine via Cu atoms as a mediator with holes in the valence band of g‐C3N4 due to their band structure position which leads to improved electron/hole separation and enhanced photocatalytic activity. The predominant active species involved in the degradation process were found to be superoxide radicals. Additionally, the photocatalyst exhibited excellent stability, retaining 88 % of its photocatalytic activity after four cycles. [ABSTRACT FROM AUTHOR]

The controllable formation of a built‐in electric field (IEF) can effectively separate photogenerated electrons and holes and optimize the band structure of a material, thus improving its photocatalytic performance. Here, a novel type of defective metal‐organic framework (MOF), i.e., an MIL‐125(Ti)@Ti‐Ce‐MOF yolk‐shell Z‐scheme heterojunction, is synthesized using a simple ion‐etching‐coupled reconstruction method. By controlling the concentration of ligand defects within the MOF heterojunction, the strength of the IEF within the heterojunction can be effectively regulated. Moreover, the experimental and theoretical results demonstrated that ligand defects within the Z‐scheme heterojunction structure can enhance the efficiency of photogenerated carrier separation and improve the transport capacity by regulating the IEF. The photocatalytic tetracycline (TC) degradation performance of the resultant MIL‐125(Ti)@Ti‐Ce‐MOF yolk‐shell heterojunction is ≈52.5‐ and 5.5‐fold higher than those of Ti‐Ce‐MOF and MIL‐125(Ti), respectively, indicating the efficient spatial charge separation due to the enhanced IEF. This study reveals the precise control of the IEF over the MIL‐125(Ti)@Ti‐Ce‐MOF yolk‐shell Z‐scheme heterojunction, elucidating the relationship between the IEF and ligand defect concentration and promoting the photocatalytic performances of MOF@MOF‐based catalysts via density functional theory and related experiments. [ABSTRACT FROM AUTHOR]

In this study, a series of CuMo1−xWxO4 solid solutions (CMWO) were prepared by adjusting the ratio of Mo to W. The morphology, phase, specific surface area, and valence state of the catalysts were characterized using SEM, TEM, XRD, BET, and XPS analysis. The photoelectric characteristics of the CuMo1−xWxO4 solid solution materials were analyzed in detail using Mott–Schottky, EIS, PL, and UV-vis DRS analysis. The experimental results show that the energy band structure of the CMWO solid solutions can be tuned to inhibit the carrier recombination under light excitation, thereby facilitating effective electron–hole pair separation. This significantly enhances the performance of photo-assisted PMS activation for tetracycline (TC) degradation. The solid solution material CMWO-3, with a Mo/W ratio of 7 : 3, achieved a TC degradation rate of 88% at pH 5. After five cycles, the TC degradation rate remained at 86%. Throughout the reaction process, photocatalysis and PMS activation exhibited a synergistic effect, generating reactive species such as SO4˙−, ˙OH, 1O2, and ˙O2−. [ABSTRACT FROM AUTHOR]

The escalating incidence of hospital infections due to antibiotic resistance necessitates the identification of alternative therapeutic agents such as probiotics. This study was designed to isolate and evaluate the efficacy of probiotics against Staphylococcus saprophyticus, a prevalent etiological agent of urinary tract infections (UTIs). A total of 100 S. saprophyticus strains were isolated from clinical samples and subjected to antibiotic susceptibility testing via the disc diffusion method. Concurrently, probiotic bacteria were isolated from Bulgarian cheese and shallot yogurt, and their antibacterial activity against S. saprophyticus strains was assessed. The inhibitory potential of probiotic supernatants was evaluated using microtiter plate assays, with the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) determined at a 1/2 dilution. Cytotoxicity was evaluated using the MTT assay, and high‐performance liquid chromatography (HPLC) was employed to analyze the concentrations of organic acids produced by the probiotics. The results revealed that all S. saprophyticus strains were resistant to tetracycline and doxycycline but susceptible to other antibiotics. Lactobacillus rhamnosus strains M and B demonstrated notable antibacterial and antibiofilm activity against S. saprophyticus isolates. These probiotics exhibited susceptibility to most antibiotics and lacked virulence factors, suggesting their safety for therapeutic use. The organic acids produced by the probiotics were identified as lactic acid, acetic acid, and formic acid. In conclusion, L. rhamnosus strains M and B exhibit potent antimicrobial properties against S. saprophyticus, indicating their potential as therapeutic agents for UTIs. Further research is warranted to validate these findings and explore the possibility of these probiotics in clinical applications. [ABSTRACT FROM AUTHOR]

Although the fundamental configuration (tetrahedron-type and capsule-type) of Zr-MOCs is well understood, the synthesis of amino-functionalized Zr-based capsule (denoted as ZrC-1-NH2) based on 2-aminoterephthalic acid remains a considerable challenge. Fortunately, we obtained single crystals under solvothermal conditions and further achieved the rapid synthesis of ZrC-1-NH2 with pure phase and high yield using a microwave-assisted solvothermal method. In addition, ZrC-1-NH2 was utilized as a photocatalyst to perform the degradation of tetracycline (TC) in water. The degradation efficiency of 92.3% was achieved at the optimal conditions, and the main active free radical was determined as ·O2− according to the trapping agent experiment and EPR results. Furthermore, the possible degradation pathway of TC was proposed. [ABSTRACT FROM AUTHOR]

Excessive use of tetracycline (TC) is alarming owing to its increased detection in water systems. In this study, a photocatalyst was developed to degrade TC using a Ce-N-co-doped AC/TiO2 photocatalyst, denoted as Ce/N-AC/TiO2, prepared using the sol–gel method assisted by microwave radiation, speeding up the synthesis process. Ce/N-AC/TiO2 achieved maximum TC degradation of 93.1% under UV light with optimum sorption system conditions of an initial concentration of 10 mg L−1, pH 7, and 30 ℃, under 120 min. Scavenger experiments revealed that holes and superoxide radicals were the active species influencing the photodegradation process. The TC degradation was appropriately fitted with Langmuir isotherms and a pseudo-second-order (PSO) kinetic model. The change in enthalpy (ΔH) (2.43 kJ mol−1), entropy (ΔS) (0.024 kJ mol−1), and Gibbs free energy (ΔG) (− 4.941 to − 5.802 kJ mol−1) suggested that the adsorption process was spontaneous, favourable, and endothermic. Electrostatic interaction, hydrogen bonding, pore-filling, cationic-π, n-π, and π-π interaction were among the interactions involved between TC and Ce/N-AC/TiO2. Furthermore, Ce/N-AC/TiO2 stability was confirmed through 80% removal efficiency even after the fifth reuse cycle. Notably, this work provides new insight into the production of efficient, reusable, and enhanced photocatalysts using a rapid and cost-effective microwave-assisted synthesis process for pollutant remediation. [ABSTRACT FROM AUTHOR]

In this work, steam-exfoliated graphitic carbon nitride was used as a promising basis for the development of photoactive materials for processes induced by visible light. Nanocrystalline cobalt(II,III) oxide, obtained by the solution combustion method followed by heat treatment of the reaction products, was used as a cocatalyst. Nanocomposite materials were prepared by joint ultrasonic treatment of graphite-like carbon nitride and cobalt(II,III) oxide in ethanol. The prepared series of samples with different weight fractions of the oxide (5–10 wt %) was studied by powder X-ray diffractometry, scanning electron microscopy, low-temperature nitrogen adsorption–desorption, and diffuse reflectance electron spectroscopy. The photocatalytic activity of the samples was evaluated in the oxidation of tetracycline hydrochloride. It was found that the rate constant of the photocatalytic reaction reached its maximum value with composites containing 7 wt % Co3O4 (k = 0.0104 min–1). The photovoltaic response studies demonstrated that the presence of cobalt oxide in the samples can significantly decrease the rate of charge carrier recombination to increase the generated current by a factor of 1.2. [ABSTRACT FROM AUTHOR]

The limited utilization of H2O2 restricts the practical application of heterogeneous Fenton oxidation technology. In this study, the flower-shaped MnFe2O4@MoS2 nanocomposite was prepared by two-step hydrothermal treatment, constructing MnFe2O4@MoS2/H2O2 system for the degradation of tetracycline (TC). Under optimized conditions, MnFe2O4@MoS2/H2O2 system fully degraded 20 mg·L−1 of TC within 60 min, and the corresponding utilization of H2O2 was also as high as 95.7%. Meanwhile, this system not only exhibited excellent cycling stability for the degradation of TC but also had good anti-interference ability against actual water sources, inorganic cations and anions and natural organic compounds. The efficient activation of H2O2 in MnFe2O4@MoS2/H2O2 system mainly relied on the redox cycling of Fe(II)/Fe(III) and Mn(II)/Mn(III) mediated by MoS2; meanwhile, the oxygen vacancies caused by redox cycling also accelerated activation of H2O2, resulting in the production of a large number of active species (·OH, ·O2− and 1O2) for rapid degradation of pollutants. The vulnerable atomic sites of TC were confirmed through theoretical calculation, and four degradation pathways of TC in MnFe2O4@MoS2/H2O2 system were proposed. Finally, the toxicity analysis confirmed that the toxicity of degradation intermediates was developing towards low toxicity. This study provided new insights into the wide application of heterogeneous Fenton systems in wastewater treatment. [ABSTRACT FROM AUTHOR]

The construction of semiconductor heterojunctions is an effective strategy to improve the photocatalytic degradation efficiency of organic pollutants. Herein, ZnPc/BiVO4 Z-scheme heterojunction was synthesized via a physical mixing method and was used for the photocatalytic degradation of tetracycline (TC) under visible light irradiation. Compared with BiVO4 and ZnPc, the 15ZnPc/BiVO4 sample exhibited improved light absorption capacity, and the electron-hole separation efficiency and redox capacity were enhanced due to the formation of the Z-scheme heterojunction. The 15ZnPc/BiVO4 composite exhibited an optimal TC degradation rate of 83.1% within 120 min. Additionally, 15ZnPc/BiVO4 exhibited excellent stability in cycling experiments, which maintained a high TC degradation rate of 79.5% after four cycles. Free radical trapping experiments indicated that superoxide radicals (·O2−) were the main active substances in the photocatalytic degradation of TC. [ABSTRACT FROM AUTHOR]

In this work, a Co–Ce@RM ozone catalyst was developed using red mud (RM), a by‐product of alumina production, as a support material, and its preparation process, catalytic efficiency, and tetracycline (TCN) degradation mechanism were investigated. A comprehensive assessment was carried out using the 3E (environmental, economic, and energy) model. The optimal production conditions for Co–Ce@RM were as follows: The doping ratio of Co and Ce was 1:3, the calcination temperature was 400°C, and the calcination time was 5 h, achieving a maximum removal rate of 87.91% of TCN. The catalyst was characterized using different analytical techniques. Under the conditions of 0.4 L/min ozone aeration rate, with 9% catalyst loading and solution pH 9, the optimal removal rates and chemical oxygen demand by the Co–Ce catalytic ozonation at RM were 94.17% and 75.27%, respectively. Moreover, free radical quenching experiments showed that superoxide radicals (O2−) and singlet oxygen (1O2) were the main active groups responsible for the degradation of TCN. When characterizing the water quality, it was assumed that TCN undergoes degradation pathways such as demethylation, dehydroxylation, double bond cleavage, and ring‐opening reactions under the influence of various active substances. Finally, the 3E evaluation model was deployed to evaluate the Co–Ce@RM catalytic ozonation experiment of TCN wastewater. Practitioner Points: The preparation of Co–Ce@RM provides new ideas for resource utilization of red mud.Catalytic ozonation by Co–Ce@RM can produce 1O2 active oxygen groups.The Co–Ce@RM catalyst can maintain a high catalytic activity after 20 cycles.The degradation pathway of the catalytic ozonation of tetracycline was fully analyzed.Catalytic ozone oxidation processes were evaluated by the "3E" (environmental, economic, and energy) model. [ABSTRACT FROM AUTHOR]