Multifunctional integration of tungsten oxide (WO3) coating: A versatile approach for enhanced performance of antibiotics against single mixed bacterial infections.

Nanomaterials containing tungsten (TNMs), characterized by diverse nanostructures had been extensively used in biomedical sector. Despite numerous reports focusing on TNM applications in specific biomedical areas, there is a noticeable absence of comprehensive studies that focused on detailed characterization of nanomaterials along with their biological applications. The present work described the structural, morphological, and antimicrobial properties of tungsten oxide (WO3) nanoparticles coated by antibiotics (nanobiotics), and their application on single and mixed bacterial culture. The nanobiotics included in this study were WO3 coated with ampicillin (W+A), WO3 coated with penicillin (P+W), and WO3 coated with ciprofloxacin (C+W). Techniques such as X-ray diffraction (XRD), scanning electron microscopy (SEM), X-ray spectroscopy (EDX), Fourier transforms infrared spectroscopy (FTIR), Rrman spectroscopy, and UV-visible spectroscopy were used to characterize synthesized nanoparticles. The minimum inhibitory concentration of C+W nanobiotic against S. aureus, E. coli, and mixed culture (S. aureus +E. coli) was lower than that of P+W and A+W. The impact of incubation period showed significant differences for each of nanobiotic against S. aureus, E. coli, and mixed culture. However, there were also non-significant differences among incubation periods for antibacterial activity of nanobiotics. It was pertinent to note that percentage variation in susceptibility of S. aureus with respect to mixed culture remained higher as compared to E. coli, indicating it stronger candidate imposing resistance. This paper thus suggested the strategy of coating of antibiotics with with WO3 nanoparticles as an ideal combination for resistance modulation against single and mixed culture bacteria.

Effects of different composting methods on antibiotic-resistant bacteria, antibiotic resistance genes, and microbial diversity in dairy cattle manures.

Composting is a common practice used for treating animal manures before they are used as organic fertilizers for crop production. Whether composting can effectively reduce microbial pathogens and antibiotic resistance genes remain poorly understood. In this study, we compared 3 different dairy manure composting methods-anaerobic fermentation (AF), static compost (SC), and organic fertilizer production (OFP)-for their effects on antibiotic-resistant bacteria, antibiotic resistance genes, and microbial community diversity in the treated manures. The 3 composting methods produced variable and distinct effects on antibiotic-resistant bacteria, zoonotic bacteria, and resistance genes, some of which were decreased and others of which showed no significant changes during composting. Particularly, SC and OFP reduced chloramphenicol resistance gene fexA and opportunistic pathogen Vibrio fluvialis, whereas AF significantly reduced tetracycline resistance gene tetB and opportunistic pathogens Enterococcus faecium and Escherichia fergusonii. The compositions of microbial communities varied significantly during the composting processes, and there were significant differences between the 3 composting methods. In all 3 composts, the dominant phyla were Firmicutes, Proteobacteria, Bacteroidetes, and Actinobacteria. Interestingly, Firmicutes, Proteobacteria, and Bacteroidetes remained stable in the entire AF process, whereas they were dominated at the beginning, decreased at the early stage of composting, and rebounded at the later stage during SC and OFP. In general, SC and OFP produced a more profound effect than AF on microbial community diversities, pathogens, and dominant species. Additionally, Enterococcus aquimarinus was isolated from AF for the first time. Phylogenetic Investigation of Communities by Reconstruction of Unobserved States function prediction analysis indicated that the genes related to membrane transport and amino acid metabolism were abundant in the 3 composts. The metabolism of amino acids, lipids, and carbohydrates increased as composting progressed. The biosynthesis of antibiotics was enhanced after fermentation in the 3 composting methods, and the increase in the SC was the most obvious. These results reveal dynamic changes in antibiotic-resistant bacteria, antibiotic resistance genes, microbial community composition, and function succession in different dairy manure composts and provide useful information for further optimization of composting practices.

Coexistence of virulence and ß-lactamase genes in avian pathogenic Escherichia coli.

Emergence of multidrug resistance in E. coli and advent of newer strains is becoming serious concern which requires keen observations. This study was designed to find the ciprofloxacin resistant E. coli isolates co-existed with multi-drug resistance along with ß-lactamase production from poultry source, and finally the genome sequencing of these strains to explore genetic variations. Study constituted on isolation of n = 225 E. coli from broiler farms of central China which were further subjected to identification of resistance against ciprofloxacin followed by antibiogram of n = 26 antibiotics and identification of ß-lactamase production. Whole genome resequencing was performed using Illumina HiSeq 4000 system. PCR results revealed predominant ß-lactamase genes i.e.CTX-M, CTX-M-1, CTX-M3, TEM-1 and OXA. Furthermore, the MDR isolates were containing most of the tested virulence genes. The most prevalent virulence genes were pap-C, fim-C, fim-H, iuc-D, irp-2, tra-T, iro-N and iut-A. The single nucleotide polymorphisms (SNPs) loci mentioned in this data give valuable genetic markers to growing high-throughput techniques for fine-determination of genotyping of MDR and virulent isolates. Characterization of SNPs on functional basis shed new bits of knowledge on the evolution, disease transmission and pathogenesis of MDR E. coli isolates. In conclusion, these findings provide evidence that most of poultry E. coli are MDR, ß-lactamase producers, and virulent which could be a zoonotic threat to the humans. The whole genome resequencing data provide higher resolution of resistance and virulence characteristics in E. coli which can further be used for the development of prevention and treatment strategies.

Genetic basis of molecular mechanisms in ß-lactam resistant gram-negative bacteria.

Antibiotic-resistant bacteria are considered one of the major global threats to human and animal health. The most harmful among the resistant bacteria are ß-lactamase producing Gram-negative species (ß-lactamases). ß-lactamases constitute a paradigm shift in the evolution of antibiotic resistance. Therefore, it is imperative to present a comprehensive review of the mechanisms responsible for developing antimicrobial resistance. Resistance due to ß-lactamases develops through a variety of mechanisms, and the number of resistant genes are involved that can be transferred between bacteria, mostly via plasmids. Over time, these new molecular-based resistance mechanisms have been progressively disclosed. The present review article provides information on the recent findings regarding the molecular mechanisms of resistance to ß-lactams in Gram-negative bacteria, including CTX-M-type ESBLs with methylase activity, plasmids harbouring phages with ß-lactam resistance genes, the co-presence of ß-lactam resistant genes of unique combinations and the presence of ß-lactam and non-ß-lactam antibiotic-resistant genes in the same bacteria. Keeping in view, the molecular level resistance development, multifactorial and coordinated measures may be taken to counter the challenge of rapidly increasing ß-lactam resistance.

RNA-seq-based transcriptome analysis of a cefquinome-treated, highly resistant, and virulent MRSA strain.

The emergence and dissemination of methicillin-resistant Staphylococcus aureus (MRSA) strains of animal origin that are resistant to several antibiotics is of great concern. Cefquinome is a fourth-generation cephalosporin developed specifically for veterinary use. The mechanism of MRSA resistance to cefquinome is still not established. Therefore, we designed this study to evaluate the effect of cefquinome on the transcriptome of MRSA1679a, a strain that was isolated from a chicken. The transcriptome analysis indicated that multiple efflux pumps (QacA, NorB, Bcr, and ABCb) were upregulated in MRSA1679a as a resistance mechanism to expel cefquinome. Additionally, penicillin-binding protein 1A was overexpressed, which conferred resistance to cefquinome, a ß-lactam antibiotic. Adhesion and the biofilm-forming capacity of the MRSA strain was also enhanced in addition to overexpression of many stress-related genes. Genes related to carbohydrate metabolism, secretion systems, and transport activity were also significantly upregulated in MRSA1679a. In conclusion, global transcription was triggered to overcome the stress induced by cefquinome, and the MRSA1679a showed a great genetic potential to survive in this challenging environment. This study provides a profound understanding of MRSA1679a as a potentially important pathogen and identifies key resistance characteristics of MRSA against cefquinome. Studies should be aimed to demonstrate multidrug resistance mechanisms of virulent strains by exposing to different antibiotic combinations.

Bringing resistance modulation to epidemic methicillin resistant S. aureus of dairy through antibiotics coupled metallic oxide nanoparticles.

The current study probed methicillin resistant S. aureus from milk of different dairy farms along with its response to multiple antibiotics, assessment of risk factors, and response to antibiotic coupled nanoparticle. XRD of Np was confirmed as miller indices (hkl) values i.e. (101), (100), (002), (110), (012) and (013) while STEM finally revealed 40-60 nm nanorods in aggregated form. Total of 6 preparations viz a viz gentamicin (G), chloramphenicol (C), zinc oxide nanoparticle (Np), gentamicin coupled Np (GNp), chloramphenicol coupled Np (CNp), and simultaneously coupling of gentamicin and chloramphenicol on Np (GCNp) were formulated for their potential to bring resistance modulation. Data analysis of this study revealed 24.59% MRSA from dairy milk appearing potentially associated (OR> 1, p < 0.05) with most of assumed risk factors. MRSA in response to various antibiotics showed highest resistance against amoxicillin (100%), penicillin (100%), vancomycin (100%), and linezolid (90%). Zone of inhibitions were increased by 249.76% (GNp), 184.86% (CNp), and 279.76% (GCNp) in case of coupled preparations. Significant reduced minimum inhibitory concentration was observed in case of GCNp (7.8125 ± 0.00 µg/mL) followed by GNp (15.00 ± 0.00 µg/mL) and CNp (41.67 ± 18.042 µg/mL) as compared to Np alone (125.00 ± 0.00 µg/mL). Minimum bactericidal concentrations for GCNp, GNp, and CNp, and Np were 31.125, 62.5, 125, and 500 µg/mL, respectively. The study thus concluded increased prevalence of MRSA while coupling of ZnO nanoparticles with antibiotics significantly brought resistance modulation to MRSA.

Phylogeny of hospital acquired MRSA, and its comparative phenotypic clinico-epidemiology with vancomycin resistant S. aureus (VRSA).

Staphylococcus aureus is emerging as complicated pathogen because of its wide-ranging origin, multiple variants, and compromised antibiotic susceptibilities. Current study was planned to find lineage of hospital acquired methicillin resistant Staphylococcus aureus (HA-MRSA), and its comparative phenotypic clinico-epidemiology with vancomycin resistant S. aureus (VRSA). A total of (n = 200) samples were aseptically collected from wound, nose, and cerebrospinal fluid of patients from metropolitan and rural background hospitals along with on spot filling in of questionnaire. Phylogenetic analysis of HA-MRSA was identified by targeting mecA gene in S. aureus. At optimal tree branch length of 1.91 and evolutionary distance 0.1, high level sequence similarity (97%-99%) was observed with different strains of S. aureus isolated from both human and animal. Non-descriptive statistics at 5% probability found 61% S. aureus, while 43.44% of them were HA-MRSA, 92.62% VRSA, and 42.62% were both MRSA and VRSA. Among assumed risk factors, use of antibiotics, venous catheterization, chronic disease, pre-hospital visits, and ICU admitted patients showed significant association (p<0.05) with pathogen. HA-MRSA was 37.50%, 80%, and 37.50% sensitive to chloramphenicol, gentamicin, and oxacillin, respectively. While <50% of VRSA were sensitive against oxacillin, enoxacin, and chloramphenicol. A significant difference (p<0.05) of percentage responses of MRSA and VRSA at resistant, intermediate, and sensitive cadre against all antibiotics except chloramphenicol was obvious in this study. The Current study concluded higher prevalence of MRSA & VRSA, significant association of risk factors, limiting antibiotic susceptibility profile, and genetic transfer at animal-human interface which suggests further studies cum preventive strategies to be planned.

Antimicrobial resistance modulation of MDR E. coli by antibiotic coated ZnO nanoparticles.

We evaluated three types of total six preparations against multidrug resistant E. coli i) three antibiotic coated ZnO nanoparticles (gentamicin coated nanoparticle-GNp; chloramphenicol coated nanoparticles-CNp; and both gentamicin & chloramphenicol coated nanoparticle-GCNp), ii) ZnO nanoparticle alone-Np, and iii) two antibiotics used in single (Gentamicin-G; and Chloramphenicol-C). A total of n = 200 sub-clinically positive mastitic milk samples of bovine origin were processed for isolation of MDR E. coli using microbiological and clinical laboratory & standard institute's protocols. ZnO Nps were prepared from zinc acetate dihydrate (Zn (CH3COO)2. 2H2O), polyethylene glycol (C2nH4n+2On+1), and urea (CH4N2O) by standard chemical protocol. Nps were characterized by XRD and STEM analyses while coating of antibiotics on Nps was confirmed by UV-Visible spectrophotometric analysis. Analysis of variance and student t-test were applied at 5% probability using SPSS version 22 statistical software for inferences on obtained data. There was significantly (p < 0.05) lowest minimum inhibitory concentrations (MICs) and highest zone of inhibitions (ZOIs) in case of GCNp (10.42 ± 4.51 µg/mL & 22.00 ± 1.00 mm) followed by GNp (20.79 ± 8.95 µg/mL & 20.00 ± 1.00 mm) and then CNp (25.96 ± 8.95 µg/mL & 12.33 ± 0.57 mm). Percentage increase in ZOI were expressed as 135.8, 78.43, and 312.76% by GCNp when compared with that of G, C, and Np, respectively. GNp and CNp coated preparations exhibited 114.36 and 275.73% increase in ZOI than to that of G and C, respectively. Similar trend was found in percentage reduction of MICs of preparations. Highest filamentation, indicator of bacterial damage, of E. coli was noted at MIC of GCNp followed by GNp and CNp. The study concluded antibiotic coated ZnO nanoparticles significant candidates modulating antibiotic resistance in MDR E. coli.

Emerging discrepancies in conventional and molecular epidemiology of methicillin resistant Staphylococcus aureus isolated from bovine milk.

Methicillin resistant Staphylococcus aureus (MRSA) is an emerging public health concern from dairy milk, and its diagnosis by phenotypic methodology is experiencing higher discrepancies. The present study was planned to estimate discrepancies in phenotypic identification of MRSA and MSSA (Methicillin sensitive Staphylococcus aureus) in relation to mecA, and prevalent risk factors from various localities. In-vitro oxacilline antibiotic disks were used for phenotypic identification of MRSA, whereas mecA gene was used as MRSA marker in Staph aureus by PCR. Total of 900 bovine milk samples from private and public farms located in district Faisalabad using convinent sampling technique were collected. Potential risk factors for MRSA prevalence identified by non-parametric statistical tests were compared among different subdistricts. Discrepancy in MRSA was calculated as percentage of mecA negative strains while that of MSSA was determined as percentage of mecA positive strains. Molecular identification presented 17.97% (55/306) of discrepancy in MRSA in terms of negative mecA strains from district Faisalabad while sub-district Faisalabad, sub-district Jaranwala, and sub-district Samundary presented 13.98% (13/93), 18.28% (17/93), and 20.83% (25/120) discrepant results, respectively. On the other hand, 29.1% (55/189) of discrepancy in MSSA in terms of mecA positive strains from MSSA isolates was noted. MSSA results were more discrepant than that of MRSA. Hence discrepancy ratio of MSSA over MRSA was noted to be 1.53, 1.50, and 1.21 from tehsil Faislabad, Samundary, and Jaranwala. Tick infestation, lactation stage, frequency of milking, dirty milker's hands, unhygienic milking procedures, and higher use of beta lactam of antibiotics were risk factors that were prevalent in increasing order from sub-district Faisalabad > Jaranwala > Samundary. The study concluded higher prevalence of MRSA in bovine milk samples, and found remarkable discrepancies in phenotypic and genotypic identification which demand immediate attention to tackle exacerbation in resistance patterns.

Development and evaluation of vaccine against Staphylococcus aureus recovered from naturally occurring mastitis in she-camels.

The predominant Staphylococcus aureus (S. aureus), an etiological agent of camel mastitis is becoming drug resistant that invites prevention and control strategies. Vaccine production would have a valuable impact on public health. Therefore, in present study, inactivated vaccine with different adjuvants was prepared and evaluated against S. aureus. The vaccinal isolate recovered from camel subclinical mastitis was coagulase positive (PCR based), having expressed pseudocapsule, holding alpha-beta hemolysin characteristics, and multiple drug resistant. Inactivated alum precipitated S. aureus vaccine (APSV) and oil adjuvant S. aureus vaccine (OASV) were prepared after confirming its antigenicity in rabbits. Three groups of rabbits were randomly inoculated with APSV, OASV, and placebo (Unvaccinated, UV). Each group was further divided into two groups based on single and booster dose inoculation. Booster dose of vaccines in rabbits at day 15th of primary inoculation was given. Serum samples were taken on 15, 30, 45 and 60 days of primary inoculation from all rabbits. Analysis of variance was applied to compare geometric mean titer (GMT) of three groups, while t-test was applied to estimate the difference between single and booster dose response. The study found 1010 CFU/mL S. aureus as standard bacterial load for vaccines with higher and sustained antigenicity. The vaccines were safe from morbidity and mortality, and proved effective and stable for 7 and 4 months at 25 °C and 37 °C, respectively. The OASV produced significantly (p < 0.05) higher immune response followed by APSV throughout trial. The highest GMT by APSV and OASV vaccines with single dose inoculation was 37.92 and 69.92 at day 45th post primary inoculation, respectively. Similarly, 59.20 and 142.40 GMTs were noted with booster dose in case of APSV and OASV, respectively. The booster dose presented significantly (p < 0.05) higher GMT than that of single dose inoculation of vaccines. The study concluded APSV and OASV safe, effective, and stable with significant immunogenic results in experimental rabbits.

Molecular epidemiology of bovine anaplasmosis in Khyber Pakhtunkhwa, Pakistan.

Bovine anaplasmosis is endemic in Pakistan where it reduces livestock productivity and leads to high mortality, especially in young animals. This study was aimed to identify the potential risk factors responsible for the occurrence and spread of anaplasmosis in cattle and buffaloes for the first time in Pakistan. A total of 900 (cattle = 479, buffalo = 421) blood samples were collected irrespective of age and sex from three distinct zones of Khyber Pakhtunkhhwa (KP) province of Pakistan. Polymerase chain reaction (PCR) technique was used for the molecular detection of anaplasmosis. Data collected on a piloted questionnaire including 11 predicting variables which were analyzed using R-statistical software, and association between the dependent and independent variables was assessed using univariable analysis. Automated and manual approaches were exercised, producing comparable models. Key risk factors identified in all the approaches included species of the animal, breed of animal, sex of animal, tick infestation status, previous tick history, tick control status, and acaricides used (odds ratio > 1). The 611 bp DNA fragment specific for 16S rRNA gene of Anaplasma spp. was produced from 165 samples. The samples were confirmed for anaplasmosis through sequencing and BLAST queries. The findings of the current study conclude that by enhancing the protective measures to control the identified risk factors can reduce the spread of anaplasmosis in Pakistan.

Deciphering the Potential of Probiotics in Vaccines.

The demand for vaccines, particularly those prepared from non-conventional sources, is rising due to the emergence of drug resistance around the globe. Probiotic-based vaccines are a wise example of such vaccines which represent new horizons in the field of vaccinology in providing an enhanced and diversified immune response. The justification for incorporating probiotics into vaccines lies in the fact that that they hold the capacity to regulate immune function directly or indirectly by influencing the gastrointestinal microbiota and related pathways. Several animal-model-based studies have also highlighted the efficacy of these vaccines. The aim of this review is to collect and summarize the trends in the recent scientific literature regarding the role of probiotics in vaccines and vaccinology, along with their impact on target populations.

Recent Global Trends in Vaccinology, Advances and Challenges.

Vaccination/immunization plays a key role in maintaining the optimum health of humans and animals where the prevalence of disease is high and treatment becomes less effective [...].

Validating Interactions of Pathogenic Proteins of Staphylococcus aureus and E. coli with Phytochemicals of Ziziphus jujube and Acacia nilotica.

This study focused on the assessment of the antimicrobial resistance of Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli) isolated from bovine mastitis milk samples and the revealing anti-mastitis potential of phytocompounds of Ziziphus jujube and Acacia nilotica through molecular docking analysis. The mastitis milk samples were collected from various dairy farms for the isolation of the bacteria (S. aureus and E. coli) and their response to antibiotics. Ethanolic extracts of both plants were prepared. Their antibacterial activity was evaluated, and they were processed for phytochemical analysis after which, molecular docking analysis with pathogenic proteins of the bacteria was carried out. Parametric and non-parametric statistical analyses were performed to reach the conclusions of this study. The findings of the study revealed a higher drug resistance (≥40%) of E. coli against ampicillin, amikacin, and vancomycin, while S. aureus exhibited the highest resistance to ampicillin, erythromycin, and ciprofloxacin. The ethanolic extracts of the Ziziphus jujube and Acacia nilotica plants produced a ZOI between 18 and 23 mm against multidrug-resistant S. aureus and E. coli. Gas chromatography-mass spectrophotometry (GC-MS) was used to explore 15 phytocompounds from Ziziphus jujube and 18 phytocompounds from Acacia nilotica. The molecular docking analysis of 2cyclopenten-1-one,3,4,4 trimethyl and Bis (2ethylhexyl) phthalate of Ziziphus jujube showed a binding affinity of -4.8 kcal/mol and -5.3 kcal/mol and -5.9 kcal/mol and -7.1 kcal/mol against the DNA Gyrase and toxic shock syndrome toxin-1 proteins of S. aureus and E. coli, respectively. The suberic acid monomethyl ester of Acacia nilotica showed a binding affinity of -5.9 kcal/mol and -5 kcal/mol against the outer membrane protein A and Topoisomerase IV protein of E. coli and -5.1 kcal/mol and -5.8 kcal/mol against the toxic shock syndrome toxin-1 and Enterotoxin B proteins of S. aureus. Similarly, 2,2,4-trimethyl-1,3-pentanediol di-iso-butyrate showed a binding affinity of -6.5 kcal/mol and -5.3 kcal/mol against the outer membrane protein A and Topoisomerase IV of E. coli and -5.2 kcal/mol and -5.9 kcal/mol against the toxic shock syndrome toxin-1 and Enterotoxin B proteins of S. aureus, respectively. The study concluded that there was an increasing trend for the antimicrobial resistance of S. aureus and E. coli, while the Ziziphus jujube and Acacia nilotica plant extracts expressed significant affinity to tackle this resistance; hence, this calls for the development of novel evidence-based therapeutics.

Recent Trends in S. aureus and E. coli-Based Endometritis, and the Therapeutic Evaluation of Sodium Alginate-Based Antibiotics and Nanoparticles.

Postpartum infection of the uterus by pathogenic bacteria is exacerbated due to a lack of sufficient epidemiological studies and evidence-based therapeutics. Therefore, this study was planned to find the prevalence, risk factors, and drug-resistance profile of S. aureus and E. coli isolated from bovine endometritis and to evaluate the antibacterial potential of sodium alginate-based antibiotics and nanoparticles. The study revealed 34.21% S. aureus and 31.57% E. coli, whereas most of the assumed risk factors presented significant association in this study. S. aureus showed the highest resistance against fusidic acid (60%) and cefoxitin (50%), while the highest resistance in E. coli was found against fusidic acid (60%), gentamicin (60%), chloramphenicol (50%), and cefoxitin (50%). Tylosin coupled with MgO nanoparticles stabilized in sodium alginate gel (Tylo + MgO + gel) presented significantly lower minimum inhibitory concentration (MIC) against E. coli, showing 13.88 ± 4.51 µg/mL after 24 h incubation. On the other hand, gel-based preparations showed MIC as 31.25 ± 0 µg/mL (Tylo + gel + MgO) and 26.04 ± 9.02 µg/mL (Tylo + Gel) against S. aureus. Generally, the MICs of non-gel-based preparations were significantly higher against bacteria except ampicillin against S. aureus in this study. The toxicity analysis of MgO nanoparticles presented 20-80% mortality of snails against a wider range of 0.01 mg/mL-10 mg/mL. The histopathological parameters concluded MgO nanoparticles safe to use on off targets. The current study thus concludes the rise in antimicrobial resistance while the gel-based products appearing as effective antimicrobials with sufficient safety margins for off-targets. The study thus invites further investigation for the development of suitable and affordable modified therapeutics for better health and production of animals.

Resistance Modulation of Individual and Polymicrobial Culture of S. aureus and E. coli through Nanoparticle-Coupled Antibiotics.

Polymicrobial mastitis is now becoming very common in dairy animals, resulting in exaggerated resistance to multiple antibiotics. The current study was executed to find drug responses in individual and mixed Culture of Staphylococcus aureus and Escherichia coli isolated from milk samples, as well as to evaluate the antibacterial potential of tungsten oxide nanoparticles. These isolates (alone and in mixed culture) were further processed for their responses to antibiotics using the disc diffusion method. On the other hand, tungsten oxide WO3 (W) nanoparticles coupled with antibiotics (ampicillin, A, and oxytetracycline, O) were prepared through the chemical method and characterized by X-ray diffraction, scanning electron microscopy (SEM), and UV-visible techniques. The preparations consisting of nanoparticles alone (W) and coupled with ampicillin (WA) and oxytetracycline (WO) were tested against individual and mixed Culture through the well diffusion and broth microdilution methods. The findings of the current study showed the highest resistance in E. coli was against penicillin (60%) and ampicillin (50%), while amikacin, erythromycin, ciprofloxacin, and oxytetracycline were the most effective antibiotics. S. aureus showed the highest resistance against penicillin (50%), oxytetracycline (40%), and ciprofloxacin (40%), while, except for ampicillin, the sensitive strains of S. aureus were in the range of 40-60% against the rest of antibiotics. The highest zones of inhibition (ZOI) against mixed Culture were shown by imipenem and ampicillin, whereas the highest percentage decrease in ZOI was noted in cases of ciprofloxacin (-240%) and gentamicin (-119.4%) in comparison to individual Culture of S. aureus and E. coli. It was noteworthy that the increase in ZOI was not more than 38% against mixed Culture as compared to the individual Culture. On the other hand, there was a significant reduction in the minimum inhibitory concentration (MIC) of nanoparticle-coupled antibiotics compared to nanoparticles alone for individual and mixed-culture bacteria, while MICs in the case of mixed Culture remained consistently high throughout the trial. This study therefore concluded that diverse drug resistance was present in both individual and mixed-culture bacteria, whereas the application of tungsten oxide nanoparticle-coupled antibiotics proved to be an effective candidate in reversing the drug resistance in bacterial strains.

Modification of the drug resistance of emerging milk-borne pathogens through sodium alginate-based antibiotics and nanoparticles.

Streptococcus agalactiae and Klebsiella pneumoniae are emerging as major milk-borne pathogens. Additionally, resistance to antibiotics of pathogens is of concern. Therefore, this study investigated the prevalence and drug resistance of S. agalactiae and K. pneumoniae in mastitis milk samples and assessed the antimicrobial potential of sodium alginate (G)-stabilized MgO nanoparticles (M) and antibiotics (tylosin [T] and ampicillin [A]) against both of these pathogens. A total of n = 200 milk samples from cattle were collected using purposive sampling, and standard microbiological approaches were adopted to isolate target bacteria. Parametric and non-parametric statistical tests were used to analyze the obtained data. Four preparations, GT (gel-stabilized tylosin), GA (gel-stabilized ampicillin), GTM (tylosin and MgO nanoparticles stabilized in gel), and GAM (ampicillin and MgO nanoparticles stabilized in gel), were evaluated against both bacteria through well diffusion and broth microdilution method. The analysis revealed that 45.24% (95/210) of the milk samples were positive for mastitis, of which 11.58% (11/95) were positive for S. agalactiae and 9.47% (9/95) were positive for K. pneumoniae. S. agalactiae had a significantly higher zone of inhibition (ZOI) than K. pneumoniae against penicillin, tetracycline, and amoxicillin, whereas the opposite was observed against imipenem and erythromycin. All gel (G)-based preparations showed an increase in the percentage of ZOI compared with antibiotics alone, with GTM presenting the highest of all, i.e., 59.09 and 56.25% ZOI compared with tylosin alone against S. agalactiae and K. pneumoniae, respectively. Similarly, in a broth microdilution assay, the lowest MIC was found for K. pneumoniae (9.766 ± 0.0 µg/mL) against GTM, followed by GT, GAM, and GA after incubation for 24 h. A similar response was noted for preparations against S. agalactiae but with a comparatively higher MIC. A significant reduction in MIC with respect to incubation time was found at 8 h and remained until at 20 h against both pathogens. The cytotoxicity of the MgO nanoparticles used in this study was significantly lower than that of the positive control. Overall, this study found that K. pneumoniae and S. agalactiae appeared higher in prevalence and antimicrobial resistance, and sodium alginate-based antibiotics and MgO nanoparticles were effective alternative approaches for tackling antimicrobial resistance.

Sodium Alginate-Based MgO Nanoparticles Coupled Antibiotics as Safe and Effective Antimicrobial Candidates against Staphylococcus aureus of Houbara Bustard Birds.

Alternative and modified therapeutic approaches are key elements in culminating antibiotic resistance. To this end, an experimental trial was conducted to determine the cytotoxicity and antibacterial potential of composites of magnesium oxide (MgO) nanoparticles and antibiotics stabilized in sodium alginate gel against multi-drug-resistant Staphylococcus aureus isolated from a houbara bustard. The characterization of preparations was carried out using X-ray diffraction (XRD), scanning transmissible electron microscopy (STEM), and Fourier-transform infrared spectroscopy (FTIR). The preparations used in this trial consisted of gel-stabilized MgO nanoparticles (MG), gel-stabilized tylosin (GT), gel-stabilized ampicillin (GA), gel-stabilized cefoxitin (GC), gel-stabilized MgO and tylosin (GMT), gel-stabilized MgO and cefoxitin (GMC), and gel-stabilized MgO and ampicillin (GMA). The study presents composites that cause a lesser extent of damage to DNA while significantly enhancing mitotic indices/phases compared to the other single component preparations with respect to the positive control (methyl methanesulphonate). It was also noted that there was a non-significant difference (p > 0.05) between the concentrations of composites and the negative control in the toxicity trial. Studying in parallel trials showed an increased prevalence, potential risk factors, and antibiotic resistance in S. aureus. The composites in a well diffusion trial showed the highest percentage increase in the zone of inhibition in the case of GT (58.42%), followed by GMT (46.15%), GC (40.65%), GMC (40%), GMA (28.72%), and GA (21.75%) compared to the antibiotics alone. A broth microdilution assay showed the lowest minimum inhibitory concentration (MIC) in the case of GMA (9.766 ± 00 µg/mL), followed by that of GT (13.02 ± 5.64 µg/mL), GMC (19.53 ± 0.00 µg/mL), GA (26.04 ± 11.28 µg/mL), GMT (26.04 ± 11.28 µg/mL), MG (39.06 ± 0.00 µg/mL), and GC (39.06 ± 0.00 µg/mL). The study thus concludes the effective tackling of multiple-drug-resistant S. aureus with sodium-alginate-stabilized MgO nanoparticles and antibiotics, whereas toxicity proved to be negligible for these composites.

Vancomycin drug resistance, an emerging threat to animal and public health.

The need to supply quality food for the growing human population has led to the revolutionization of food production and processing in recent years. Meanwhile, food production sources are at risk of microbial attack, while the use of antibiotics to counter them is posing another threat to food safety and security. Vancomycin was used as the first line of defense against multiple drug-resistant bacteria salient of which is methicillin-resistant S. aureus. The emergence of the vancomycin resistance gene in bacteria impairs the efficacy of antibiotics on the one hand while its harmful residues impart food safety concerns on the other. Currently, a novel set of resistance genes "Van cluster" is circulating in a wider range of bacteria. Considerable economic losses in terms of low production and food safety are associated with this emerging resistance. The current review focuses on the emergence of vancomycin resistance and its impact on food safety. The review proposes the need for further research on the probable routes, mechanisms, and implications of vancomycin resistance from animals to humans and vice versa.

Role of Bacteriophages for Optimized Health and Production of Poultry.

The poultry sector is facing infections from Salmonella, Campylobacter, Listeria and Staphylococcus spp., and Escherichia coli, that have developed multidrug resistance aptitude. Antibiotics cause disturbances in the balance of normal microbiota leading to dysbiosis, immunosuppression, and the development of secondary infections. Bacteriophages have been reported to lower the colonization of Salmonella and Campylobacter in poultry. The specificity of bacteriophages is greater than that of antibiotics and can be used as a cocktail for enhanced antibacterial activity. Specie-specific phages have been prepared, e.g., Staphylophage (used against Staphylococcus bacteria) that specifically eliminate bacterial pathogens. Bacteriophage products, e.g., BacWashTM and Ecolicide PX have been developed as antiseptics and disinfectants for effective biosecurity and biosafety measures. The success of phage therapy is influenced by time to use, the amount used, the delivery mechanism, and combination therapy with other therapeutics. It is a need of time to build a comprehensive understanding of the use of bacteriophages in poultry production. The current review thus focuses on mechanisms of bacteriophages against poultry pathogens, their applications in various therapeutics, impacts on the economy, and current challenges.