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Klebsiella species are becoming a major global public health concern. In particular, the increase in multidrug‐resistant strains is a cause for concern. This study was aimed at determining the antibiotic susceptibility of two different isolates of Klebsiella quasipneumoniae subsp. similipneumoniae and determining the virulence characteristics and bacterial morphology under subminimum inhibitory concentrations (sub‐MICs) of antibiotics. In this study, two multidrug‐resistant K. quasipneumoniae subsp. similipneumoniae isolates were identified, one of which was clinical, and the other was isolated from freshwater. The MICs of the antibiotics meropenem, chloramphenicol, ciprofloxacin, and kanamycin were determined for these isolates. The effects of the sub‐MICs on the virulence and morphological characteristics of the bacteria were investigated in comparison with K. pneumoniae (ATCC 13883). The MICs of meropenem, chloramphenicol, ciprofloxacin, and kanamycin were 0.04, 20, 2, and 8 μg/mL in the clinical isolate; 0.2, 15, 5, and 2 μg/mL in the freshwater isolate; and 0.03, 3, 0.1, and 0.3 μg/mL for K. pneumoniae. The biofilm‐forming ability of K. quasipneumoniae subsp. similipneumoniae isolates decreased with antibiotic sub‐MICs. Siderophore activity increased only with MIC/4 of kanamycin and MIC/2 of chloramphenicol in the clinical isolate (p > 0.05). Furthermore, bacterial morphology and expression of virulence genes were affected differently by the sub‐MICs. This study showed that biofilm formation decreased and that the changes in bacterial morphology and expression of virulence genes were very different in the presence of 1/2 and 1/4 sub‐MIC antibiotics. [ABSTRACT FROM AUTHOR]

Starvation of Escherichia coli thyA auxotrophs for the required thymine or thymidine leads to the cessation of DNA synthesis and, unexpectedly, to thymineless death (TLD). Previously, TLD-alleviating defects were identified by the candidate gene approach, for their contribution to replication initiation, fork repair, or SOS induction. However, no TLD-blocking mutations were ever found, suggesting a multifactorial nature of TLD. Since (until recently) no unbiased isolation of TLD suppressors was reported, we used enrichment after insertional mutagenesis to systematically isolate TLD suppressors. Our approach was validated by isolation of known TLD-alleviating mutants in recombinational repair. At the same time, and unexpectedly for the current TLD models, most of the isolated suppressors affected general metabolism, while the strongest suppressors impacted the central metabolism. Several temperature-sensitive (Ts) mutants in important/essential functions, like nadA , ribB , or coa A, almost completely suppressed TLD at 42°C. Since blocking protein synthesis completely by chloramphenicol prevents TLD, while reducing protein synthesis to 10% alleviates TLD only slightly, we measured the level of protein synthesis in these mutants at 42°C and found it to be 20–70% of the WT, not enough reduction to explain TLD prevention. We conclude that the isolated central metabolism mutants prevent TLD by affecting specific TLD-promoting functions. [ABSTRACT FROM AUTHOR]

Canine urinary excretion of chloramphenicol was evaluated to optimize a dosing protocol for treating urinary tract infections. Seven healthy male intact purpose‐bred Beagles and six healthy client‐owned dogs of various breeds each received a single oral 50 mg/kg dose of chloramphenicol. Urine was collected at baseline, and 6, 8, 12, and 24 h after chloramphenicol. Chloramphenicol urine concentrations were measured and compared to the epidemiological cutoff value for E. coli (16 mcg/mL). At 8 h, mean chloramphenicol concentration from all dogs was 266.9 mcg/mL (90% CI 136.2–397.7 mcg/mL) but was lower in Beagles than client‐owned dogs. At 12 h, mean chloramphenicol concentration from all dogs was 111.0 mcg/mL (90% CI 36.9–185.0 mcg/mL) and was lower in Beagles (10.6 mcg/mL, 90% CI 1.4–19.8 mcg/mL) than client‐owned dogs (228.0 mcg/mL, 90% CI 103.0–353.1 mcg/mL). Urine half‐life was similar for all dogs (1.8–3.8 h). This justifies dosing chloramphenicol 50 mg/kg PO q 8 h. All client‐owned dogs additionally maintained concentrations well above 16 mcg/mL, for 12 h, suggesting that q 12‐h dosing might be appropriate for non‐Beagle dogs with susceptible lower urinary tract infections. A clinical trial in dogs with urinary tract infections is needed as well as further investigation into potential breed differences. [ABSTRACT FROM AUTHOR]

Background Sepsis and pneumonia in the elderly comprise a significant portion of medical admissions. Chloramphenicol has been used in Israel for treatment of bacterial infections, without evidence regarding its efficacy and safety. Objectives We aimed to examine whether chloramphenicol was associated with similar outcomes to ceftriaxone, for treatment of sepsis and pneumonia in the elderly with dementia and functional disability. Methods Patients over 75, with dementia and functional disability, admitted to the internal medicine ward at Beilinson Hospital between 2011 and 2021, with community-acquired aspiration pneumonia or sepsis of undetermined source were included. Patients with mild dementia and independent in their activities of daily living were excluded. Primary outcome was 30- and 90-day all-cause mortality. A propensity-weighted multivariable model was constructed using inverse probability of treatment weighting. Results were expressed as OR with 95% CI. Results In total, 1558 patients were included: 512 treated with chloramphenicol and 1046 with ceftriaxone. The cohort consisted of elderly patients (mean age 87 ± 6.2 years) with comorbidities; 30- and 90-day all-cause mortality were similar [222/512 (43.3%) versus 439/1046 (41.9%) P  = 0.602, and 261/512 (50.9%) versus 556/1046 (53.1%) P  = 0.419, respectively]. Propensity-weighted, logistic multivariable analysis for 30- and 90-day all-cause mortality revealed similar mortality rates for chloramphenicol and ceftriaxone (OR 1.049 95% CI 0.217–1.158, OR 0.923 95% CI 0.734–1.112, respectively). Conclusion In this retrospective cohort of elderly debilitated patients hospitalized with pneumonia and sepsis, we found no difference in 30- and 90-day mortality between those treated with chloramphenicol or ceftriaxone. Further studies should determine the efficacy and safety of chloramphenicol in this population. [ABSTRACT FROM AUTHOR]

5-Fluorouracil (5-FU) is a first-line treatment for colorectal cancer, but side effects such as severe diarrhea are common in clinical use and have been linked to its induction of normal cell senescence. Chloramphenicol (CAP) is an antibiotic commonly used to treat typhoid or anaerobic infections, but its senescence-related aspects have not been thoroughly investigated. Here, we used 5-FU to induce senescence in human umbilical vein endothelial cells (HUVECs) and investigated the relationship between CAP and cellular senescence at the cellular level. In a model of cellular senescence induced by 5-FU treatment, we discovered that CAP treatment reversed the rise in the percentage of senescence-associated galactosidase (SA-β-gal)-positive cells and decreased the expression of senescence-associated proteins (p16), senescence-associated genes (p21), and senescence-associated secretory phenotypes (SASPs: IL-6, TNF-α). In addition, CAP subsequently restored the autophagic process inhibited by 5-FU and upregulated the levels of autophagy-related proteins. Mechanistically, we found that CAP restored autophagic flux by inhibiting the mTOR pathway, which in turn alleviated FU-induced cellular senescence. Our findings suggest that CAP may help prevent cellular senescence and restore autophagy, opening up new possibilities and approaches for the clinical management of colorectal cancer. [ABSTRACT FROM AUTHOR]

The peculiar one-pot reaction involving Carbaldehydes, malononitrile, and indane 1,3-dione was used to explain the alternative synthesis of indeno-pyridine and indeno-pyran derivatives. The synthesis of indeno-pyridine or indeno-pyran derivatives has been examined based on an effective modification in the Michael addition of indane 1,3-dione or malononitrile on Knoevenagel product throughout the reaction process. The reaction required up to 30 min to complete utilizing CuO nanoparticles (NPs) in water at room temperature, making the approach innovative and environmentally benign. All of the produced compounds have been validated using spectroscopic data. And they were then tested for their antimicrobial activities. All tested compounds showing greater efficacy against Sertaconazol and Chloramphenicol. [ABSTRACT FROM AUTHOR]

In this study, molecular identification of Lactiplantibacillus pentosus v390 was performed using 16S rRNA gene analysis with FYM27 and R1492 primers. The viability of the strain was assessed under acidic conditions at pH 2.5, 3.5 and 4.5, and resistance to bile at concentrations of 0%, 0.3%, 0.5%, and 0.7% was investigated. Antioxidant activity, cholesterol absorption, hydrophobicity, potential for DNase enzyme production, biogenic amines, hemolytic activity, and resistance to common therapeutic antibiotics were evaluated. The antimicrobial effect of the strain against pathogenic bacteria (Shigella dysenteriae, Salmonella enterica serovar Typhimurium, Escherichia coli, Staphylococcus aureus, Listeria monocytogenes, and Bacillus subtilis) was examined using the well and disk diffusion method. The results showed that the L. pentosus v390 strain had the ability to survive at different pH levels, but after three hours of storage at pH 2.5, the bacterial count decreased. The strain demonstrated growth capability at various bile salt concentrations. L. pentosus v390 was intermediate to the antibiotic Nitrofurazone, resistant to Nalidixic and Imipenem antibiotics, and sensitive to Vancocin, Gentamicin, Chloramphenicol, Penicillin, and Ciprofloxacin antibiotics. The hydrophobicity, antioxidant activity (DPPH and ABTS), and cholesterol absorption of the strain were 46.50 ± 0.38%, 37.20 ± 0.40%, 39.90 ± 0.45%, and 36.50 ± 0.47%, respectively. No DNase enzyme production, biogenic amines, or hemolytic activity were observed from the strain. L. pentosus v390 exhibited stronger antimicrobial effects against Gram -positive bacteria. The results indicated that L. pentosus v390 has desirable probiotic properties that require further research to confirm its application potential in food product development. [ABSTRACT FROM AUTHOR]

Straw, a predominant agricultural residue, represents a significant waste product. Harnessing its potential is of paramount importance both in terms of research and economic value. In this study, chemically pretreated corn straw was infused with distinct microbial fungal mycelium variants and subsequently transformed into a series of biochars through a process involving carbonization and activation. The findings revealed enhancements in the specific surface area and total pore volume of mycelium-doped straw biochars compared to the original corn straw biochar (BCS). Additionally, discernible disparities were observed in their physical and chemical attributes, encompassing functional groups, surface chemistry, and micro-morphology. Notably, in water-based antibiotic removal experiments focusing on tetracycline hydrochloride (TH) and chloramphenicol (CP), the mycelium-doped straw biochars outperformed BCS. Their maximum adsorption capacities for TH and CP surpassed those of alternative adsorbents, including other biochars. Impressively, even after five cycles, the biochar exhibited a removal rate exceeding 80%, attesting to its robust stability. This study successfully emphasized the efficacy of incorporating fungal mycelium to enhance the adsorption properties of straw-based biochar, introducing a new theoretical basis for the development of lignocellulosic materials. [ABSTRACT FROM AUTHOR]

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The primary goal was to enhance the stability and bioavailability of chloramphenicol for ophthalmic use without compromising patient comfort, such as causing blurry vision. This study employed a 2-level full factorial design to optimize the formulation, exploring different concentrations of poloxamer 407 and HPMC to achieve this objective. [ABSTRACT FROM AUTHOR]

Background: Klebsiella quasipneumoniae (previously known as K. pneumoniae K6) strains are among the multidrug-resistant hypervirulent bacterial pathogens. Phage therapy can help treat infections caused by such pathogens. Here we report some aspects of virology and therapeutic potentials of vB_KquU_ 9K11K6, a bacteriophage that infects Klebsiella quasipneumoniae. Methods: K. quasipneumoniae (ATCC 700603) was used to screen wastewater lytic phages. The isolate vB_KquU_çKuK6 that consistently created large clear plaques was characterized using standard virological and molecular methods. Results: vB_KquU_çKuK6 has a complex capsid with an icosahedral head (~60 nm) and a slender tail (~140 nm x 10 nm). The phage has a 51% AT-rich linear dsDNA genome (51,251 bp) containing 121 open reading frames. The genome contains genes encoding spanin, endolysin, and holin proteins necessary for lytic infection and a recombinase gene possibly involved in lysogenic infection. vB_KquU_çKuK6 is stable at -80 to +67°C, pH 4-9, and brief exposure to one volume percent of chloroform. vB_KquU_çKuK6 has a narrow host range. Its lytic infection cycle involves a latency of 20 min and a burst size of 435 plaqueforming units. The phage can cause lysogenic infection, and the resulting lysogens are resistant to lytic infection by vB_KquU_çKuK6. vB_KquU_çKuK6 reduces the host cells' ability to form biofilm but fails to eliminate that ability. vB_KquU_çKuK6 demonstrates phage-antibiotic synergy and reduces the minimum inhibitory concentration of chloramphenicol and neomycin sulfate by about 8 folds. Conclusion: vB_KquU_çKuK6 cannot be directly used for phage therapy because it is a temperate bacteriophage. However, genetically modified strains of vB_KquU_çKuK6 alone or combined with antibiotics or other lytic Klebsiella phages can have therapeutic utilities in treating K. quasipneumoniae infections. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: Electrocatalysis technology can effectively promote the hydrodechlorination of chloramphenicol (CAP) to reduce the bio‐toxicity. However, there are still some challenges such as low degradation rate and poor stability. Here, we prepared porous N, O co‐doped carbon supported Pd nanoparticles composites (Pd NPs/NO‐C) for electrocatalytic degradation of CAP. The doping of N and O not only effectively enhanced the interaction between substrate and CAP, promoting the mass transfer process, but also enhanced the anchoring effect on Pd nanoparticles, avoiding the occurrence of aggregation. The prepared composites achieved removal efficiency of CAP over 99% within 1 h, and the rate constant was as high as 6.72 h–1, outperforming previous reported electrocatalysts. Additionally, Pd NPs/NO‐C composites showed a wide range of pH tolerance, excellent ion interference resistance and long‐term stability. Our work unravels the importance of mass transfer processes in solution to electrocatalytic hydrodechlorination and provides new research ideas for catalysts design. [ABSTRACT FROM AUTHOR]

Ubiquitin (Ub) signals are recognized and decoded into cellular responses by Ub-receptors, proteins that tether the Ub-binding domain(s) (UBDs) with response elements. Typically, UBDs bind mono-Ub in highly dynamic and weak affinity manners, presenting challenges in identifying and characterizing their binding interfaces. Here, we report the development of a new approach to facilitate the detection of these weak interactions using split-reporter systems where two interacting proteins are proximally co-translated from a single mRNA. This proximity significantly enhances the readout signals of weak protein–protein interactions (PPIs). We harnessed this system to characterize the ultra-weak UBD and ENTH (Epsin N-terminal Homology) and discovered that the yeast Ent1-ENTH domain contains two Ub-binding patches. One is similar to a previously characterized patch on STAM1(signal-transducing adaptor molecule)-VHS (Vps27, Hrs, and STAM), and the other was predicted by AlphaFold. Using a split-CAT selection system that co-translates Ub and ENTH in combination with mutagenesis, we assessed and confirmed the existence of a novel binding patch around residue F53 on ENTH. Co-translation in the split-CAT system provides an effective tool for studying weak PPIs and offers new insights into Ub-receptor interactions. [ABSTRACT FROM AUTHOR]

A photocatalytic electrochemical aptasensor for the detection of chloramphenicol（CAP）antibiotic residues in water by utilizing SYBR Green I（SG）and chemically exfoliated MoS 2 （ce-MoS 2 ） as synergistically signal-amplification platforms. [Display omitted] • A novel photocatalytic electrochemical aptasensor was developed for the detection of chloramphenicol (CAP) antibiotic residues in water. • Photosensitized SYBR Green I (SG) and chemically stripped MoS 2 (ce-MoS 2) were intercalated into the groove of the resulting dsDNA and use as a synergistic signal-amplification platform. • Upon light irradiation, the photocatalytic reaction was activated, generating singlet oxygen that efficiently cleaved the dsDNA, leading to a significant increase in the current of [Fe(CN) 6 ]3-/4-. • The aptasensor demonstrated good selectivity towards CAP in the presence of interfering antibiotics. • The aptasensor exhibited a linear relationship between CAP and logarithmic concentrations from 20 to 1000 nM, with a detection limit (3σ) of 3.391 nM. This study reports the development of a photocatalytic electrochemical aptasensor for the purpose of detecting chloramphenicol (CAP) antibiotic residues in water by utilizing SYBR Green I (SG) and chemically exfoliated MoS 2 (ce-MoS 2) as synergistically signal-amplification platforms. The Au nanoparticles (AuNPs) were electrodeposited onto the surface of an indium tin oxide (ITO) electrode. After that, the thiolate-modified cDNA, also known as capture DNA, was combined with the aptamer. Subsequently, photosensitized SG molecules and ce-MoS 2 nanomaterial were inserted into the groove of the resultant double-stranded DNA (dsDNA). The activation of the photocatalytic process upon exposure to light resulted in the generation of singlet oxygen. The singlet oxygen effectively split the dsDNA, resulting in significant enhancement in the current of [Fe(CN) 6 ]3-/4-. When the CAP was present, both SG molecules and ce-MoS 2 broke away from the dsDNA, which turned off the photosensitization response, leading to significant reduction in the current of [Fe(CN) 6 ]3-/4-. Under the optimal conditions, the aptasensor exhibited a linear relationship between the current of [Fe(CN) 6 ]3-/4- with logarithmic concentrations of CAP from 20 to 1000 nM, with a detection of limit (3 σ) of 3.391 nM. The aptasensor also demonstrated good selectivity towards CAP in the presence of interfering antibiotics, such as tetracycline, streptomycin, levofloxacin, ciprofloxacin, and sulfadimethoxine. Additionally, the results obtained from the analysis of natural water samples using the proposed aptasensor were consistent with the findings acquired through the use of a liquid chromatograph-mass spectrometer. Therefore, with its simplicity and high selectivity, this aptasensor can potentially detect alternative antibiotics in environmental water samples by replacing the aptamers based on photosensitization. [ABSTRACT FROM AUTHOR]

This study aimed to count Enterobacteriaceae and Escherichia coli in different locations on pig carcasses (shank, loin, abdomen, shoulder, and jowl) from two slaughterhouses (A and B) between September 2019 and July 2021 during different slaughter stages (after bleeding, after passing through the epilator machine, after manual toileting in the dirty area, before and after evisceration, and after the final washing), as well as verify antimicrobial resistance and biofilm formation capacity. The main points of Enterobacteriaceae and E. coli contamination were identified in the two slaughterhouses through three collections. The stages with the highest counts were post-bleeding and evisceration in both slaughterhouses and after manual toileting in slaughterhouse B in the first collection. Most E. coli isolates were resistant to multiple antimicrobials, with higher resistance frequencies to amoxicillin, ampicillin, chloramphenicol, sulfonamides, and streptomycin. The virulence genes eae, stx1, and stx2 were also detected. Three isolates had all three genes and exhibited resistance to at least six antimicrobial classes (β-lactams, macrolides, aminoglycosides, sulfonamides, amphenicols, and quinolones). E. coli isolates also showed a high frequency of strains with moderate and strong in vitro biofilm-forming capacity. This is the first study to characterize microbial contamination by pig slaughter stage in the Federal District region, demonstrating the critical points for hygienic production. E. coli was isolated from the surface of pig carcasses, as well as the virulence genes stx1, stx2, and eae were detected. The multi-antimicrobial resistant isolates also had a moderate-to-strong biofilm formation capacity, thus demonstrating risks to public health. [ABSTRACT FROM AUTHOR]

Chloramphenicol (CAM), a well-known broad-spectrum antibiotic, inhibits peptide bond formation in bacterial ribosomes. It has been reported to affect ribosome assembly mainly through disrupting the balance of ribosomal proteins. The present study investigates the multifaceted effects of CAM on the maturation of the 50S ribosomal subunit in Escherichia coli (E. coli). Using label-free quantitative mass spectrometry (LFQ-MS), we observed that CAM treatment also leads to the upregulation of assembly factors. Further cryo-electron microscopy (cryo-EM) analysis of the ribosomal precursors characterized the CAM-treatment-accumulated pre-50S intermediates. Heterogeneous reconstruction identified 26 distinct pre-50S intermediates, which were categorized into nine main states based on their structural features. Our structural analysis highlighted that CAM severely impedes the formation of the central protuberance (CP), H89, and H58 during 50S ribosomal subunit maturation. The ELISA assay further demonstrated the direct binding of CAM to the ribosomal precursors, suggesting that the interference with 50S maturation occurs through a combination of direct and indirect mechanisms. These findings provide new insights into the mechanism of the action of CAM and provide a foundation for a better understanding of the assembly landscapes of the ribosome. [ABSTRACT FROM AUTHOR]

Pyropia haitanensis was cultured under two CO2 (410 (LC), 1000 (HC) μL L-1) concentrations and six chloramphenicol (CAP)-methanol solutions (0, 0+methanol, 10, 50, 100, 250 μg mL-1) to investigate the effects of elevated CO2 and CAP on its growth, photosynthesis and biochemical characteristics. HC had no obvious effects on the growth rate (RGR) with CAP in the range of 10 to 100 μg mL-1, but the decrease of RGR by HC was statistically significant with the CAP dosage at 250 μg mL-1. HC had no significant effect on net photosynthetic rates (Pn) in the present of CAP (10-250 μg mL-1). CAP greatly reduced net photosynthesis as well as the maximal photochemical yield (Fv/Fm) and photosynthetic efficiency (αETR). In contrast, the maximum relative electron transport rates (rETRm) were almost constant with the CAP dosage from 10 to 100 μg mL-1. HC significantly increased the energy fluxes (per RC) for absorption (ABS/RC), trapping (TRo/RC) and transport fluxes (ETo/RC) with the dosage of CAP at 250 μg mL-1. Principal component analysis (PCA) indicated that CAP was positively correlated with the synthesis of free amino acids (FAA), contents of umami-, sweet- and essential AA were significantly enhanced with the interaction of HC and higher CAP dosage at 100 μg mL-1, which led to the variation of flavor in algae. Furthermore, phycobiliproteins and soluble protein (SP) contents were remarkably reduced by CAP. Contents of chlorophyll a (Chl a), carotenoids (Car), soluble carbohydrates (SC) and C/N ratios were almost unchanged among treatments. The study indicates that future ocean acidification has no obvious effects on the biomass productivity of P. haitanensis, maintained steady photosynthetic activities with the CAP (within 100 μg mL-1) and induces better flavor. The data obtained have important theoretical relevance for in-depth understanding of algal responses to global changes and oceanic contamination. [ABSTRACT FROM AUTHOR]

Drug contamination is one of the most dangerous categories of impurities, which can be mitigated by photocatalysis reaction. Despite the unignorable advantage of nanophotocatalyst, their separation from batch reaction is challenging. Herein, a developed equipment is presented based on immobilizing a nanocatalyst onto the surface of a non-soluble polymeric substrate to degrade high amounts of chloramphenicol and amitriptyline under UV radiation. At first, polyvinyl alcohol plates were prepared through cross-linking by C6H9NaO7 in the presence of C5H8O2 and then characterized according to the water uptake amount and measuring water contact angle. The nanocatalyst was prepared by mixing two separate core–shell suspensions of Fe3O4@SiO2 and WO3@TiO2; afterward, Fe3O4@SiO2–WO3@TiO2 was sprayed onto the surface of the plates. The materials were characterized by X-ray diffraction spectroscopy, FTIR analysis, scanning electron microscopy, energy dispersive X-ray spectrometry, elemental mapping analysis, thermogravimetric analysis, Brunauer−Emmett−Teller and diffuse reflectance spectroscopy. The degradation recovery was optimized with respect to pH, UV radiation time and nanocatalyst amount. The adsorption efficiency, degradation efficiency, reusability, reproducibility, durability, effect of interference ions, adsorption isotherm, adsorption kinetic, photocatalytic kinetic and degradation mechanism were studied and explained. Analytical greenness metric approach is reported. Four different water samples were successfully employed as real samples. [ABSTRACT FROM AUTHOR]

Chloramphenicol (CAP) is widely used in human and veterinary medicine but has a harmful side effect on human/animal health and ecological risks. The current methods for the detection of CAP are commonly expensive, complex and time-wasting. Herein, a simple, low-cost and high-effective electrochemical sensor is constructed for the detection of CAP using rationally designed pitch-derived porous carbon (PPC) as the conducting medium. The modification of PPC on the glassy carbon electrode is adopted to realize the amplification of electrochemical signal, and then the aptamers with negative charge are introduced to the PPC-functionalized electrode to attract the positively charged CAP and to enhance hydrophilicity of the modified electrode. The electrochemical performance of the fabricated sensor is investigated using cyclic voltammetry and differential pulse voltammetry, showing a fast current change and high-selectivity for the detection of CAP, and exhibiting outstanding sensing performance with a wide linear range of 1.0–500 μM and a low detection limit of 0.1 μM. In addition, the sensor also shows excellent repeatability (RSD = 4.1%), reproducibility (RSD = 5.0%), stability (RSD = 8.3%) and high selectivity. Moreover, the constructed sensor is capable of precisely detecting CAP in real water samples with recoveries of 93.0% to 102.8% and relative standard deviations of less than 4.5%. [ABSTRACT FROM AUTHOR]

This study aimed to determine chloramphenicol residues and bacterial contamination (Aerobic Plate Count-APC, Escherichia coli count, Salmonella sp., and Vibrio cholerae) in farmed African catfish (Clarias gariepinus) that are marketed in Banyuwangi, Indonesia. A total of ninety samples of C. gariepinus were collected from several markets in Banyuwangi, namely, Kertosari, Blambangan, and Banyuwangi Kota. Using standard procedures, APC, E. coli count, Salmonella sp., V. cholerae, and chloramphenicol residues were determined. 36.37% of samples from Kertosari markets; 23.33% of samples from Banyuwangi Kota markets; and 16.67% of samples from Blambangan markets contained chloramphenicol residues, but less than 0.3 ppb. Only 40% of samples from Kertosari markets, 36.67% of samples from Banyuwangi Kota markets, and 26.67% of samples from Blambangan markets were contaminated by E. coli, but were less than 3 MPNg-1. The highest APC was from Banyuwangi Kota, followed by Kertosari and Blambangan. No samples were contaminated by Salmonella sp. and V. cholerae from any of the markets, and there was no significant difference between all markets in APC, E. coli count, or chloramphenicol residues. All farmed catfish marketed in Banyuwangi were safe to eat because no samples exceeded the maximum chloramphenicol residue and bacterial contaminant standards. Further studies are needed to detect other antibiotic residues used in aquaculture, including tetracycline, sulphonamide, enrofloxacin, and nitrofuran. [ABSTRACT FROM AUTHOR]

Environmental and public health risks may arise from the presence of antibiotic residues, and specifically chloramphenicol in food samples. Therefore, it is quite important for researchers to detect chloramphenicol. In this work, PDA@CuFe2O4 nanoparticles were synthesized and characterizsed. The PDA@CuFe2O4 nanoparticles that had been prepared were used to create PDA@CuFe2O4/GCE, which was then used to detect chloramphenicol electrochemically in a 0.1 M phosphate buffer solution (pH 7). The study focused on the electrochemical properties, including changes in scan rate, sensing, and pH influence. Compared to the unmodified electrode, the PDA@CuFe2O4/GCE electrode exhibits better sensing properties. The advantage of the PDA@CuFe2O4/GCE electrode is that it shows unique electrochemical sensing toward individual and chloramphenicol detection; for instance, it has a low detection of 0.12µM for chloramphenicol detection and a high sensitivity of 16.25A µM−1 cm−2 for chloramphenicol detection. [ABSTRACT FROM AUTHOR]

The "antenna effect" is one of the most important energy transfer modes in lanthanide light-emitting polymers. In this study, novel luminescent nanostructured coordination polymers (Eu–PCP) were synthesized in one step using Eu3+ as the central metal ion and 5,10,15,20-tetrakis (4-carboxyphenyl) porphyrin (TCPP) as the organic ligand. The unique "antenna effect" observed between Eu3+ and TCPP leads to a substantial improvement in the electrochemiluminescence (ECL) emission efficiency. Eu–PCP exhibits good cathodic ECL characteristics. Additionally, Au@SnS2 nanosheets exhibit favorable electrical conductivity, biocompatibility, and a significant specific surface area. This makes them a suitable choice as substrate materials for the modification of electrode surfaces and capturing antigens. Being well known, the development of sensitive and rapid methods to detect chloramphenicol is essential for food safety. Based on this, we report a novel competitive electrochemiluminescence immunoassay to achieve ultra-sensitive and highly specific detection of chloramphenicol. The linear range was 0.0002–500 ng mL−1 and the detection limit was 0.09 pg mL−1. Apart from that, the experimental results proved that it provided a new analytical tool for the detection of antibiotic residues in food safety. [ABSTRACT FROM AUTHOR]

Background: Antimicrobial resistance (AMR) of Neisseria gonorrhoeae (NG) is a significant public health concern. Objective: The objective of our study was to assess global AMR rates and test them both temporally and geographically. Methods: We conducted a systematic search of relevant reports from international databases up to 2021. The R statistical package was used for all statistical analyses. Results: A total of 225 articles were analyzed, and 432,880 NG isolates were examined. The weighted pooled resistance (WPR) rate of different antibiotics was as follows: ciprofloxacin, 51.6%; tetracycline, 45.4%; trimethoprim/sulfamethoxazole, 42.4%; chloramphenicol, 4.1%; kanamycin, 2.1%; gentamicin, 0.6%; and spectinomycin, 0.3%. The resistance to spectinomycin, gentamicin, and kanamycin decreased over time. Significant differences in antibiotic resistance rates were found between the countries. Conclusion: Our findings reveal a continuous increase in resistance to some antibiotics (tetracycline and ciprofloxacin) historically used for gonorrhea, even after discontinuation. However, encouraging trends of decreasing resistance to spectinomycin, gentamicin, and kanamycin were observed. Continued global monitoring of AMR profiles in NG isolates is essential for informing appropriate treatment strategies and mitigating the threat of untreatable gonorrhea. [ABSTRACT FROM AUTHOR]

The application of antibiotics in the poultry and veterinary sectors is very common practice in India. Owing to the seriousness of antimicrobial resistance (AMR), the present study has illustrated the overall scenario of AMR in the poultry and veterinary sectors in India through an in-depth scoping review and key informant interview (KII). In the poultry sector, most of the studies reviewed have reported resistant bacteria isolated from chicken meat, eggs, cloacal swabs, and fecal samples, and only a few have reported the presence of resistant bacteria in and around the environment of poultry farms. The major resistant bacteria that have been reported are E. coli, Salmonella spp., S. aureus, Campylobacter jejuni, and K. pneumoniae. These bacterial isolates exhibited resistance to various antibiotics, such as azithromycin (21.43%), tetracycline (11.30-100%), chloramphenicol (4.76-100%), erythromycin (75-83.33%), ciprofloxacin (5.7-100%), gentamicin (17-100%), amikacin (4.76%), cotrimoxazole (42.2-60%), trimethoprim (89.4%), ceftriaxone (80%), and cefotaxime (14.29-70%). Like the poultry sector, different antibiotics are also used for treating clinical and subclinical bovine mastitis, which is one of the major problems plaguing the dairy sector. Several AMR bacterial strains, such as E. coli, Staphylococcus aureus, S. epidermidis, and Klebsiella pneumoniae, have been reported by many researchers and showed resistance against tetracycline (74%), oxytetracycline (47.37%), ciprofloxacin (51%), streptomycin (57.89%), cephalosporin (100%), and trimethoprim (70%). The KIIs have revealed several reasons behind these AMR scenarios, of which the growing need for the production of food animals and their products with inadequate infrastructure and a lack of proper knowledge on farm management among the farmers are the major ones. Though several government legislations and policies have been laid down, proper implementation of these policies, strict surveillance on antibiotic application in the poultry and veterinary sectors, awareness generation among farmers, and infrastructure development can help minimize the development and transmission of AMR bacteria within and from these sectors. [ABSTRACT FROM AUTHOR]

In this work, the photo-, electro-, and photo-electro-oxidation of chloramphenicol was investigated. The photo-experiments were carried out with different irradiation sources (an ultraviolet and a simulated solar source) using self-doped titanium nanotubes (SDTNT), a very promising and innovative material that deserves further investigations in the degradation of different pollutants. The photo-electrooxidation (j = 15 mA cm–2) under simulated solar irradiation presented the best efficiency, with ca. 100% degradation and kinetic constant of k = 0.04427 min–1. The FTIR analysis demonstrated a structural modification of the standard molecule occurred for all conditions used, suggesting a modification in functional groups responsible for the biological activity. Furthermore, the TOC analysis showed a significant mineralization of the pollutant (66% from the initial concentration). In addition, both photo-electrooxidation approaches have demonstrated a positive value of S, where the simulated solar irradiation reached the highest value S = 0.6960. The experimental results pointed out evidence that the methodology employed herein for chloramphenicol degradation is greatly interesting and the photo-electrooxidation under simulated solar irradiation is a promising approach for this purpose. [ABSTRACT FROM AUTHOR]

Metal–organic frameworks (MOFs) constitute an assorted class of multi-dimensional materials that offer the potential to serve as luminescent sensors for the sensitive and selective detection of antibiotics in wastewater. Herein, a new Zn(II)-based MOF with the formula [Zn(PMA)0.5(bbp)·H2O·DMA] (1) (bbp = 3,5-bis(benzoimidazo-1-ly)pyridine; PMA = pyromellitic acid) was synthesized by a solvothermal method and characterized. Crystallographic analysis reveals that MOF 1 possesses a 4,4-connected net with the Schläfli symbol {32·4·52·6}2{32·42·52}. The fabricated MOF exhibited luminescent property and was employed as a luminescent sensor to sensitively and selectively detect tetracycline (TCY) antibiotic amongst thiamphenicol (THI), 2-methyl-4-chlorophenoxyacetic acid (MCPA), tetracycline (TCY), sulfamethoxazole (SMT), thiabendazole (TBZ), tinidazole (TDZ), sulfadiazine (SDZ), chloramphenicol (CAP), metamitron (MMT), and dinotefuran (DTF). Further, restoration of the emissive response of TCY@1 was achieved by adding salicylic acid with a concomitant bathochromic shift in the emissive response. The possible sensing mechanism and restoration of emissive response were assessed with the aid of theoretical calculations. [ABSTRACT FROM AUTHOR]

Oxidative degradation of chloramphenicol (CAP) using a hybrid approach (US/HA+/n-Fe2O3/SPC) involving sodium percarbonate (SPC; "solid H2O2" carrier), Fe2O3 nanoparticles (n-Fe2O3; H2O2 decomposition catalyst), hydroxylamine in its protonated form (HA+; Fe (III) to Fe (II) reducer), and ultrasonic cavitation (to increase the generation of hydroxyl radicals) has been studied for the first time. The average size of n-Fe2O3 synthesized by the sonochemical method, as calculated according to the Debye–Scherrer equation, was ~ 18 nm. The maximum degradation degree of CAP (83.1%) and first-order oxidative degradation rate constant of CAP as 1.253 × 10–3 s−1 were achieved using the modified sono-Fenton process under the optimized conditions as the initial concentration of CAP – 50 mg/L, the molar ratio of CAP:HA+:n-Fe2O3:SPC of 1:100:100:100, pH as 3, the temperature as 318 K, the specific ultrasonic power as 53.3 W/L, and the treatment duration of 7200 s. In general, the efficiency and intensity of CAP degradation increased with a decrease in the pH value, an increase in the molar ratio of CAP:HA+:n-Fe2O3:SPC, a decrease in the initial concentration of CAP, an increase in temperature, and showed a minor change with the specific power of US. The synergistic coefficient for the combination of the US and the heterogeneous Fenton process was 17.9. The active participation of hydroxyl radicals in the oxidative degradation of CAP using the modified sono-Fenton process was confirmed by scavenging experiments performed using tert-butyl alcohol. The proposed process can be a promising direction in the remediation of pharmaceutical effluents with significant potential for commercial exploitation. [ABSTRACT FROM AUTHOR]

Food-borne Vibrio parahaemolyticus has global economic and public health concern. The frequent way for humans to contract these bacteria is through seafood. In this study, 350 samples were analysed for the presence of Vibrio parahaemolyticus. Of those, 40 samples were found positive for the bacteria. Ten different antibiotics were used to test the antibiotic sensitivity of these 40 isolates, and they exhibited variable susceptibility pattern. The isolates showed 100% resistance to penicillin G followed by 80% and 75% resistance to ampicillin and streptomycin, respectively. The isolates were highly sensitive to ciprofloxacin (97.5%), followed by trimethoprim (90%), gentamicin (90%), chloramphenicol (87.5%), amikacin (80%), tetracycline (65%) and cephalothin (65%). Of the 40 isolates, 45.0%, 22.5%, 5.0%, 7.5% isolates were found resistant to 3, 4, 5 and 6 antibiotics, respectively. Multiple antibiotic resistance (MAR) index value above 0.2 was shown by 80% of the isolates. The presence of MAR highlights the essential need to determine drug susceptibility and monitor antimicrobial resistance profiles. This is crucial for enhancing food safety and protecting public health. By identifying resistant strains, we can develop more effective treatment strategies and implement measures to control the spread of resistant pathogens, thus preserving antibiotic efficacy and ensuring public well-being. [ABSTRACT FROM AUTHOR]

Toxic intermediates in food caused by chloramphenicol (CP) and furazolidone (FZ) have gained interest in research toward their detection. Hence, fast, reliable, and accurate detection of CP and FZ in food products is of utmost importance. Here, a novel molybdenum disulfide-connected carbon nanotube aerogel/poly (3,4-ethylenedioxythiophene) [MoS2/CNTs aerogel/PEDOT] nanocomposite materials are constructed and deposited on the pretreated carbon paste electrode (PCPE) by a facile eletropolymerization method. The characterization of MoS2/CNTs aerogel/PEDOT nanocomposite was analyzed by scanning electron microscopy (SEM), cyclic voltammetry, and differential pulse voltammetry. The modified MoS2/CNTs aerogel/PEDOT nanocomposite has improved sensing characteristics for detecting CP and FZ in PBS solution. For this work, we have studied various parameters like electrocatalytic activity, the effect of scan rates, pH variation studies, and concentration variation studies. Under optimum conditions, the modified electrode exhibited superior sensing ability compared to the bare and pretreated CPE. This improvement in electrocatalytic activity can be the higher conductivity, larger surface area, increased heterogeneous rate constant, and presence of more active sites in the MoS2/CNTs aerogel/PEDOT nanocomposite. The modified electrode demonstrated distinct electrochemical sensing toward the individual and simultaneous analysis of CP and FZ with a high sensitivity of 0.701 µA. µM−1.cm−2 for CP and 0.787 µA. µM−1.cm−2 for FZ and a low detection limit of 3.74 nM for CP and 3.83 nM for FZ with good reproducibility, repeatability, and interferences. Additionally, the prepared sensor effectively detects CP and FZ in food samples (honey and milk) with an acceptable recovery range and a relative standard deviation below 4%. [ABSTRACT FROM AUTHOR]

N-doped hollow carbon spheres (NHCSs) with different shell thicknesses are constructed using various amounts of SiO2 precursor. An interconnected framework with diminished wall thickness ensures an efficient and continuous electron transport which helps to enhance the performance of NHCS. Improvement of the electrocatalytic performance was shown in the determination of antibiotic drug chloramphenicol (CAP) due to the unique hollow thin shell morphology, ample defect sites, accessible surface area, higher surface-to-volume ratio and an synergistic effect. Boosted electrocatalytic activity of 1.5 N-doped HCS (1.5 NHCS) was applied to detect CAP with a linear range and detection limit of 1–1150 µM and 0.098 µM (n = 3), respectively, with superior storage stability and considerable sensitivity. These results suggest that the proposed work can be successfully applied to the determination of CAP in milk and water samples. [ABSTRACT FROM AUTHOR]

ESBL-producing Escherichia coli strains threaten public health and obligate the use of last-resort antibiotics. This study identified 15 E. coli isolates through 16S rRNA and gyrB genes, specific to E. coli, in 120 egg samples (12.5%). Antibiotic resistance was detected according to the EUCAST and CLSI in E. coli isolates. 2 isolates were susceptible to all antibiotics, one isolate was resistant to one antibiotic, one isolate was resistant to 2 antibiotics, and 11 E. coli isolates (73.3%) had multidrug resistance. Most frequent antibiotic resistances were detected against ampicillin (80%), tetracycline (66.6%), and chloramphenicol (66.6%). A double-disc confirmation test was used to detect ESBL production, and bla TEM, bla SHV, bla CTX-M and bla OXA genes were searched by PCR. The bla TEM (100%) gene was found in all resistant E. coli isolates, and the bla CTX-M gene was detected in only 3 (20%) E. coli isolates. None of the E. coli isolates contained the genes responsible for carbapenem and colistin resistance. Our results show that multi-drug antibiotic resistance and the bla TEM gene are frequent in E. coli from table eggs in Istanbul. This is the first preliminary study on ESBL-producing E. coli isolates in table eggs in Türkiye. [ABSTRACT FROM AUTHOR]

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Residues of drugs used in poultry farming are recognized as significant pollutants, posing potential risks to consumer health. Among these, antibiotics are widely administered to combat infectious diseases, with residues frequently detected in various products, including chicken meat. Given the high consumption of chicken in the country, it is crucial to monitor commonly used antibiotics such as chloramphenicol and florfenicol in these products. In this study, a combined method of microwave-assisted extraction and homogenous liquid-liquid microextraction was employed to extract chloramphenicol and florfenicol from chicken meat samples. The extracted antibiotics were subsequently analyzed using high-performance liquid chromatography with a diode array detector. Under optimal conditions, extraction recoveries were 60% for chloramphenicol and 66% for florfenicol, demonstrating the method’s efficiency. The detection limits were 0.20 ng/g for chloramphenicol and 0.17 ng/g for florfenicol, indicating the method’s sensitivity to low concentrations. Notably, florfenicol residues were detected in two of the ten chicken samples tested.

Single walled carbon nanotubes (SWCNTs) sensors known for its sensitivity, fast response and ability to operate at room temperature. However, obtaining high sensitivity, reproducibility, stability, selectivity and cost effective SWCNT based sensors for detection of antibiotics in different environment remains challenging. In this work, we have fabricated a highly sensitive single-walled carbon nanotubes modified carbon material paste electrode modified (nanotubes/MCPE) and used it to electrochemically detect antibiotics (CP, FZ) and potassium ferrocyanide K4 [Fe (CN)6]. The electrochemical sensing parameters, including variations in scan rates, sensing, and electrode surface area, were determined. The nanotubes-modified electrode exhibited better sensing properties as compared to the unmodified electrode. The modified electrode demonstrated distinct electrochemical sensing towards individual and simultaneous detection of CP and FZ. The nanotubes/MCPE shows diffusion-controlled electron transfer process with wide linear concentration range from 50 to 750 µM for CP and 50 to 400 µM for FZ, with a low limit of detection of 13.71 nM for CP and 9.51 nM for FZ, and a high sensitivity of 2.420 µA. µM− 1.cm− 2 for CP and 3.487µA. µM− 1.cm− 2 for FZ. The electron transfer properties of SWCNT, CP, and FZ are computed using density functional theory the results are in good agreement with experimental results. Additionally, the developed SWCNT-based sensor exhibits remarkable repeatability, reproducibility, stability, and satisfactory recovery results for CP and FZ detection in honey and milk samples. [ABSTRACT FROM AUTHOR]

Dayak tribes indigenous to the Indonesian island of Borneo has been using Bajakah Kalalawit (Uncaria gambir Roxb.) as traditional medicine for ages. This inspired us to develop phenolic from Bajakah Kalalawit extract as antibacterial agent. The extraction was done through decoction method and the determination of phenolic concentration was done using a visible spectrophotometer and Folin–Ciocalteu reagent (mixture of phosphotungstic and phosphomolybdic acids). We investigated the possibility of developing phenolic nanoparticle for future work. Kirby-Bauer method was used to assess antibacterial activity of phenolic against Staphylococcus aureus and the results were compared to Chloramphenicol in terms of its efficacy and duration of inhibition. This study contributes to the ongoing effort to address antibiotic resistance through the development of innovative antibacterial agents derived from natural sources. The results provide valuable insights into the potential of Bajakah Kalalawit phenolic extracts as a promising avenue for combating bacterial infections in the future. [ABSTRACT FROM AUTHOR]

Objectives: Antimicrobial resistance (AMR) poses a worldwide challenge, threatening global health. The objective of this research was to determine the 3rd generation cephalosporin resistance (3GCR) proportion in Escherichia (E.) coli isolated from clinical samples of dogs and cats in Germany. Methods: The study utilized result data from antimicrobial susceptibility testing (AST) of isolates obtained from diagnostic samples collected from dogs and cats send in for bacterial examination. Data includes AST results from 3,491 veterinary practices in Germany spanning the years 2019 to 2021, representing 33.1% of practices and clinics nationwide. Out of 175,171 clinical samples, a total of 25,491 E. coli strains (14,6%) were evaluated for their susceptibility to antimicrobials, in particular the 3rd generation cephalosporin cefovecin, but also aminoglycosides (gentamicin, GEN), fluoroquinolones (enrofloxacin, ENR), tetracyclines (doxycycline), phenicols (chloramphenicol), folate pathway inhibitors (sulfamethoxazole + trimethoprim), and nitrofurans (nitrofurantoin). Results: The cefovecin resistance proportion was 11.6% in the study period. Geographical analysis showed local variations in 3GCR in E. coli of ±3%. Regarding all E. coli isolates investigated, resistance proportions were observed as follows: 12% for sulfamethoxazole-trimethoprim, 7% for enrofloxacin, 8% for chloramphenicol and 4% for gentamicin. Notably, 3GCR E. coli showed significantly higher resistance proportions, specifically 30% for sulfamethoxazole-trimethoprim, 28% for chloramphenicol, 18% for enrofloxacin and 14% for gentamicin. Conclusions: This study represents the first of its kind to utilize an extensive dataset encompassing dogs and cats across Germany. Companion animals have close contact to their owners and transmission of 3GCR between them is likely as well as acquisition from other environmental sources. Resistance proportions (6.7%) against the antibiotic ceftazidime as reported by the German AMR surveillance for human medicine were lower than in our veterinary data. Our study provides an overview of the current 3GCR resistance proportion in Germany and demonstrates the importance of integrated AMR monitoring. [ABSTRACT FROM AUTHOR]

Background: Due to the increasing emergence of antibiotic resistance in Enterococcus faecalis (E. faecalis), it indicated as potentially opportunistic pathogen causing various healthcare-associated and life-threatening diseases around the world. Objective: The aim of this meta-analysis was to evaluate the weighted pooled resistance rates in clinical E. faecalis isolates based on over time, areas, antimicrobial susceptibility testing (AST), and infection source. Methods: We searched the studies in PubMed, Scopus, and Web of Science (November 30, 2022). All statistical analyses were carried out using the statistical package R. Results: The analysis encompassed a total of 74 studies conducted in 28 countries. According to the meta-regression, the chloramphenicol, fosfomycin, imipenem, linezolid, minocycline, norfloxacin, quinupristin-dalfopristin, and tetracycline resistance rate increased over time. Analysis revealed statistically significant differences in antibiotic resistance rates for ampicillin, chloramphenicol, erythromycin, gentamicin, penicillin, rifampicin, teicoplanin, tetracycline, and vancomycin across various countries. Conclusions: Globally, the prevalence of drug resistant E. faecalis strains are on the increase over time. Daptomycin and tigecycline can be an effective agent for the treatment of clinical E. faecalis infections. Considering the low prevalence of antibiotic resistance in continents of Europe and Australia, it is suggested to take advantage of their preventive strategies in order to obtain efficient results in other places with high prevalence of resistance. [ABSTRACT FROM AUTHOR]

With the increasing misuse of antibiotic drugs, the convenient and ultrasensitive detection of chloramphenicol (CAP) is essential for ensuring food safety and human health. In this study, a comprehensive platform was developed integrating detection and discrimination capabilities by combining surface-enhanced Raman scattering (SERS) with lateral flow immunoassay (LFIA) technology, along with a support vector machine (SVM) model for data analysis, to detect CAP residues in aquatic products. The CAP-specific antibody-modified gold nanostars (Au NSs) were synthesized as SERS–LFIA nanoprobes, achieving an ultralow limit of detection (LOD) of 10 pg/mL and a theoretical LOD of 1.6 pg/mL for simulated aquatic samples. This sensitivity surpasses that of the currently available commercial strips and demonstrates high specificity. Additionally, the automated discrimination model exhibited high sensitivity (95.83%) and specificity (96.43%) as well as an accuracy of 96% on the test set, marking an 8% improvement over traditional Raman intensity discrimination methods. This developed platform is a simple, fast, and automated technique that eliminates the need for sample pretreatment, offering a promising approach for the trace detection of CAP in aquatic products. [ABSTRACT FROM AUTHOR]

Rapid, efficient, versatile, easy-to-use, and non-expensive analytical approaches are globally demanded for food analysis. Many ambient ionization approaches based on electrospray ionization (ESI) have been developed recently for the rapid molecular characterization of food products. However, those approaches mainly suffer from insufficient signal duration for comprehensive chemical characterization by tandem MS analysis. Here, a commercially available disposable gel loading tip is used as a low-cost emitter for the direct ionization of untreated food samples. The most important advantages of our approach include high stability, and durability of the signal (> 10 min), low cost (ca. 0.1 USD per run), low sample and solvent consumption, prevention of tip clogging and discharge, operational simplicity, and potential for automation. Quantitative analysis of sulfapyridine, HMF (hydroxymethylfurfural), and chloramphenicol in real sample shows the limit-of-detection 0.1 μg mL−1, 0.005 μg mL−1, 0.01 μg mL−1; the linearity range 0.1–5 μg mL−1, 0.005–0.25 μg mL−1, 0.01–1 μg mL−1; and the linear fits R2 ≥ 0.980, 0.991, 0.986. Moreover, we show that tip-ESI can also afford sequential molecular ionization of untreated viscous samples, which is difficult to achieve by conventional ESI. We conclude that tip-ESI–MS is a versatile analytical approach for the rapid chemical analysis of untreated food samples. [ABSTRACT FROM AUTHOR]

Oral Veillonella species are among the early colonizers of the human oral cavity. We constructed a small, single-selectable-marker shuttle plasmid, examined its ability to be transformed into diverse oral Veillonella strains, and assessed its potential use for expressing a gene encoding an oxygen-independent fluorescent protein, thus generating a fluorescent Veillonella parvula strain. Because tetracycline resistance is common in Veillonella , we replaced genes encoding ampicillin- and tetracycline-resistance in a previously described shuttle plasmid (pBSJL2) with a chloramphenicol acetyltransferase gene. The resulting plasmid pCF1135 was successfully introduced into four strains representing V. parvula and V. atypica by either natural transformation or electroporation. We then modified this plasmid to express a gene encoding an oxygen-independent fluorescent protein in V. parvula SKV38. The resulting strain yielded a fluorescence signal intensity ∼16 times higher than the wild type in microplate-based fluorimetry experiments. While fluorescence microscopy demonstrated that planktonic cells, colonies, and biofilms of fluorescent V. parvula could also be imaged, photobleaching was a significant issue. In conclusion, we anticipate this genetic system and information provided here will facilitate expanded studies of oral Veillonella species' properties and behavior. [ABSTRACT FROM AUTHOR]

Vibrioparahaemolyticus is a gram-negative motile bacterium inhabiting marine, estuarine, and coastal environments. It is a critical aquatic pathogen in shrimp farming, and strains possessing pir A and pir B toxins can cause acute hepatopancreatic necrosis disease (AHPND) in shrimps. The study aimed to isolate V. parahaemolyticus from the gut and hepatopancreas of shrimps from the selected districts of Tamil Nadu for a duration of 6 months from December 2022 to May 2023 by random sampling, and thirty-two strains were confirmed as V. parahaemolyticus from 110 presumptive bacterial isolates. All 32 isolates used in the AP4 PCR protocol failed to detect any isolates carrying AHPND pir toxins (pir A and pir B). Forty-four percent of isolates have shown β-haemolytic activity on blood agar. Of the 32 isolates, two, eleven, and twenty-nine harboured tdh, trh, and T3SS1 genes, respectively, and none of them possessed T3SS2 gene. Isolates of V. parahaemolyticus were resistant to gentamycin, vancomycin, and erythromycin and highly susceptible to ciprofloxacin, ofloxacin, chloramphenicol, amoxyclav, trimethoprim, streptomycin, cefoxitin, and ceftazidime. AMR genes encoding qnrA, tet A, blaSHV, and aac-3-IIa were present in 6%, 16%, 16%, and 22% of the isolates. AMR genes catA1 and str B were negative for all 32 isolates. It is concluded that the prevalence and incidence of V. parahaemolyticus were 29% in the studied coastal districts of Tamil Nadu. All isolates were found to be negative for AHPND. Hence, shrimp farms in the studied area were free from infection of AHPND. [ABSTRACT FROM AUTHOR]

Bacterial cytoplasmic organelles are diverse and serve many varied purposes. Here, we employed Rhodobacter sphaeroides to investigate the accumulation of carbon and inorganic phosphate in the storage organelles, polyhydroxybutyrate (PHB) and polyphosphate (PP), respectively. Using cryo-electron tomography (cryo-ET), these organelles were observed to increase in size and abundance when growth was arrested by chloramphenicol treatment. The accumulation of PHB and PP was quantified from three-dimensional (3D) segmentations in cryo-tomograms and the analysis of these 3D models. The quantification of PHB using both segmentation analysis and liquid chromatography and mass spectrometry (LCMS) each demonstrated an over 10- to 20-fold accumulation of PHB. The cytoplasmic location of PHB in cells was assessed with fluorescence light microscopy using a PhaP-mNeonGreen fusion-protein construct. The subcellular location and enumeration of these organelles were correlated by comparing the cryo-ET and fluorescence microscopy data. A potential link between PHB and PP localization and possible explanations for co-localization are discussed. Finally, the study of PHB and PP granules, and their accumulation, is discussed in the context of advancing fundamental knowledge about bacterial stress response, the study of renewable sources of bioplastics, and highly energetic compounds. [ABSTRACT FROM AUTHOR]

Limited literature exists on chloramphenicol's clinical use. In this retrospective, single-center case-series, we examined 183 chloramphenicol-treated and 81 piperacillin-tazobactam-treated medical patients. Chloramphenicol recipients were older, more debilitated, cognitively impaired, and penicillin allergic, while increased need for inotropics, higher leukocyte count, and higher creatinine levels were notable in the piperacillin-tazobactam group. Pneumonia was the most common indication, with no mortality difference between groups. While acknowledging its antimicrobial activity and potential benefit in specific conditions such as pneumonia, further clinical studies are needed to assess the role of chloramphenicol in the setting where other alternatives are available. [ABSTRACT FROM AUTHOR]

Haematococcus lacustris (Girod-Chantrans) Rostafinski (Chlorophyta) is the richest microalgal source of astaxanthin. Natural astaxanthin from H. lacustris has been widely studied and used for commercial production worldwide. In this study, we examined the effects of 11 antibiotics (dihydrostreptomycin sulphate, neomycin, chloramphenicol, penicillin, streptomycin, ampicillin, kanamycin, gentamycin, hygromycin B, tetracycline, and paromomycin) on the biomass dry weight, growth, and astaxanthin yield of H. lacustris using Jaworski's medium without a nitrogen source. Astaxanthin content in H. lacustris was improved in the presence of ampicillin (0.25 g/L, 0.5 g/L, 1 g/L), chloramphenicol (0.25 g/L), and penicillin (0.25 g/L, 0.5 g/L, 1 g/L) in comparison to the control on day 15. The greatest increase in astaxanthin content on day 15 (6.69-fold) was obtained with the addition of penicillin (0.5 g/L) in comparison to the control. Similarly, on day 15, the cell numbers were also the highest for the H. lacustris culture grown with the addition of penicillin (0.5 g/L). [ABSTRACT FROM AUTHOR]

A new coordination polymer (CP) with composition [Zn3(bpyp)2(TCB)2(H2O)2]n (1) has been engendered by performing reaction of Zn(II) with 1,3,5‐tris‐(4‐carboxyphenyl)benzene (H3TCB) and 2,5‐bis(pyrid‐4‐yl)pyridine (bpyp) under solvothermal condition. The single crystal X‐ray diffraction analysis for 1 suggests kgd topological behavior having resemblance with a tessellation composed of diamond shapes arranged in a star pattern and represented by the Schläfli symbol {41}2{42·62·81}. This newly designed CP exhibits optical band gap of 2.92 eV and employed as photocatalyst for photodegradation of antibiotics, namely, nitrofurazone (NFZ), chloramphenicol (CAP), sulfasalazine (SLA), oxytetracycline (OXY), and furazolidone (FZD). Among these antibiotics, 1 displays best photocatalytic activity against the photodegradation of NFZ and under optimized conditions viz. photocatalyst dosage of 15 mg, and initial NFZ concentration of 40 ppm, the CP 1 displays best catalytic performance and photo‐decomposed 93.04% NFZ with pseudo first order rate constant k of 0.04502 min−1 in 1 h. The likely photocatalytic mechanism has been evaluated using theoretical calculations. [ABSTRACT FROM AUTHOR]

Chloramphenicol (CAP) is an antibiotic that is used to treat a range of human ailments and is also utilized in animal medicine. However, long-term usage of CAP can have substantial side effects in humans. Hence, precise and sensitive analytical approaches for CAP detection are required. We developed an electrochemical sensor based on a ZnO/MWCNT nanocomposite for the efficient measurement of chloramphenicol (CAP) in this study. Aqueous leaf extract of Rhoeo discolor (Tradescantia spathacea) was employed in the green production of ZnO nanoparticles. A simple sonochemical approach was used to combine ZnO nanoparticles with MWCNT. UV–Visible spectroscopy, X-ray diffraction (XRD), scanning electron microscopy (SEM), elemental mapping, Transmission Electron Microscopy (TEM), and Fourier transform infrared spectroscopy (FTIR) have been utilized to describe the synthesized ZnO nanoparticles. The electrochemical performance of the ZnO/MWCNT/graphite electrode was studied using cyclic voltammetry (CV) and linear sweep voltammetry (LSV). The effect of loading mass, pH, and scan rate on electrode reaction was also determined. The ZnO/MWCNT/graphite electrode has a linear response in the range of 1 to 250 μM, a high sensitivity of 11.15 μA μM−1 cm−2, with a LOD of 0.35 μM and LOQ of 1.16 μM. It also has good reproducibility and stability. Real samples like honey and milk were used to illustrate the sensor's viability. [ABSTRACT FROM AUTHOR]

Salmonella is one of the major food pathogens in the broiler industry. Subtyping of Salmonella is critical to monitor and trace its existence in chicken processing lines. Therefore, the present work evaluated the antibiotic resistance and characterisation of Salmonella Typhimurium isolated from the chicken slaughterhouse. A total of 1,100 colonies of tentative Salmonella were isolated and identified using biochemical tests and polymerase chain reaction (PCR). From these 1,100 colonies, 474 were identified as Salmonella spp., while 18 were S. Typhimurium. Antibiotic resistance against nine types of antibiotics was examined for the 18 isolates of S. Typhimurium, namely amoxicillin (10 μg), ampicillin (10 μg), chloramphenicol (30 μg), gentamicin (10 μg), penicillin (10 μg), streptomycin (10 μg), sulfamethoxazole (25 μg), tetracycline (30 μg), and vancomycin (30 μg). It was found that these isolates were resistant to at least four antibiotics or more, while the multiple antibiotic resistance (MAR) index value was 0.64. All S. Typhimurium isolates were resistant to amoxicillin, ampicillin, penicillin, and vancomycin, followed by tetracycline (55.6%, n = 10/18), gentamicin (44.4%, n = 8/18), chloramphenicol (38.9%, n = 7/18), streptomycin (27.8%, n = 5/18), and sulfamethoxazole (11.1%, n = 2/18). A total of 12 antibiograms were observed; A1 - A12. Plasmid’s size ranged from 3 to > 24 kbp, and seven plasmid profiles (P1 - P7) were observed, while Enterobacterial repetitive intergenic consensus-polymerase chain reaction (ERIC-PCR) showed 12 ERIC-PCR fingerprinting (E1 - E12). GelCompar II software discriminated the S. Typhimurium into four clusters and five single isolates at 80% similarity. The antibiogram, plasmid profiling, and ERIC-PCR fingerprinting revealed significant genetic heterogeneity in S. Typhimurium strains indicating that consumers could face high contamination risk from consuming chickens obtained from the studied slaughterhouse. [ABSTRACT FROM AUTHOR]

As a broad-spectrum antibiotic, chloramphenicol has an important contribution in resisting bacterial diseases. It has been widely used in medicine and animal husbandry, but it has the disadvantages of long-term unreasonable use and slow degradation in nature. Long-term consumption of food contaminated by chloramphenicol will cause serious side effects to human beings. Therefore, it is urgent to establish an effective method to remove chloramphenicol from wastewater. Co/Ni@ZrO2 photocatalyst with nanosphere structure was prepared by hydrothermal method and used for the degradation of chloramphenicol (CAP).The structure, morphology and optical properties of the samples were characterized by TEM, SEM, XPS, XRD, FT-IR and UV-Vis. Under visible light, 12% Co/Ni@ZrO2 has good photocatalytic performance for the degradation of chloramphenicol, which may be due to the synergistic effect and nano-limitation effect between Co/Ni and ZrO2. When the optimal dosage of catalyst is 50 mg / L and the initial concentration of chloramphenicol is 20 mg / L, the degradation rate is 98.2 % within 150 min. XPS and Raman results showed that there were appropriate amount of oxygen vacancies on the surface of ZrO2, which accelerated the electron transfer rate in the system and inhibited the recombination of photoelectron-hole pairs under visible light, thus improving the activation efficiency of dissolved oxygen in chloramphenicol solution. Free radical capture experiments showed that· O2-,· OH, h+ were the main active substances for the degradation of chloramphenicol. The possible mechanism of chloramphenicol degradation under visible light was speculated. The results show that Co/Ni@ZrO2 is a promising photocatalyst for wastewater treatment. A schematic diagram of charge separation and transfer during the degradation of chloramphenicol by 12wt % CoNi @ ZrO2 nanospheres [ABSTRACT FROM AUTHOR]