Effects of abiotic factors on the stability and infectivity of polyvalent coliphage

Abstract Bacteriophage has attracted growing interest as a promising therapeutic agent for pathogenic bacteria, especially for antibiotic-resistant bacteria. However, the various abiotic conditions could impact the stability of phages and further threat host-virus interactions. Here, we investigated the stability and lytic activity of virulent polyvalent coliphage (named PE1) by double-layer plaque assay. PE1 can efficiently infect both the drug-sensitive Escherichia coli K12 and multidrug-resistant E. coli NDM-1 even after prolonged storage at 4 °C up to two months. Results showed that PE1 exhibits an outstanding stability to infect E. coli strains under a wide range of thermal (4 °C–60 °C) and pH (4–11) conditions, which covers the thermal and pH variations of most wastewater treatment plants. Moreover, PE1 exhibited high resistibility to heavy metals exposure including Cu2+, Cd2+, Co2+, and Cr3+ at the concentrations below 0.5 mM, and an excellent resistant ability to the variation of ionic strength, which still retained strong infectious ability even treated with saturated sodium chloride solution (350 g/L). This work shows that polyvalent phage PE1 has a strong adaptive capacity to various abiotic factors and should be a good candidate of being an antibacterial agent, especially for antibiotic-resistant bacteria control in sewage.

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Prevalence of Multidrug-Resistant Bacteria from U.S.-Grown and Imported Fresh Produce Retailed in Chain Supermarkets and Ethnic Stores of Davidson County, Tennessee

Journal of Food Protection ◽

10.4315/0362-028x.jfp-16-178 ◽

2017 ◽

Vol 80 (3) ◽

pp. 506-514 ◽

Cited By ~ 11

Author(s):

Siqin Liu ◽

Agnes Kilonzo-Nthenge

Keyword(s):

Pathogenic Bacteria ◽

Fresh Produce ◽

Agricultural Practices ◽

Multidrug Resistant ◽

Leafy Vegetables ◽

Resistant Bacteria ◽

Antibiotic Resistant Bacteria ◽

Antibiotic Resistant ◽

E Coli ◽

Public Health Hazards

ABSTRACTThe aim of this study was to determine whether U.S.-grown and imported fresh produce retailed in ethnic stores and chain supermarkets was a reservoir of antibiotic-resistant bacteria. A total of 360 (129 imported and 231 U.S.-grown) samples of fresh produce were purchased from retail stores and analyzed for Enterobacteriaceae, including three pathogenic bacteria (Escherichia coli O157:H7, Shigella, and Salmonella), using standard methods. Presumptive pathogenic isolates were confirmed using PCR. The mean Enterobacteriaceae counts for imported produce were 6.87 ± 0.15 log CFU/g and 7.16 ± 0.11 log CFU/g in ethnic stores and chain supermarkets, respectively. For U.S.-grown produce, the contamination levels were at 8.35 ± 0.17 log CFU/g and 7.52 ± 0.13 log CFU/g in ethnic stores and chain supermarkets, respectively. Salmonella (0 and 0.3%), Shigella (1.7 and 0.6%), E. coli (3.1 and 1.4%), Enterobacter (9.4 and 8.6%), Klebsiella (6.7 and 0.6%), and Serratia (5.8 and 1.4%) were detected in produce from ethnic stores and chain supermarkets, respectively. None of the samples were positive for E. coli O157:H7. Regarding distribution by produce type, leafy vegetables had a significantly (P < 0.05) higher prevalence of Enterobacteriaceae (19.2%) than the other types, followed by root vegetables (6.4%), tomatoes (5.6%), and fruits (3.9%). Antibiotic-resistant Salmonella, Shigella, E. coli, Enterobacter, Klebsiella, and Erwinia bacteria were also isolated from fresh produce. The frequencies of vancomycin resistance (98.1 and 100%) were significantly higher (P < 0.05) than the frequencies of ampicillin resistance (42.3 and 72.9%) for imported and U.S.-grown produce, respectively. Despite the increased attention to the role of imported produce as a source of antimicrobial resistance, this study indicates that U.S.-grown produce is also contaminated with antibiotic-resistant bacteria. Good agricultural practices on the farms and washing of fresh produce before consumption are greatly recommended to avoid possible public health hazards.

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Multiresistant Bacteria Isolated from Intestinal Faeces of Farm Animals in Austria

Antibiotics ◽

10.3390/antibiotics10040466 ◽

2021 ◽

Vol 10 (4) ◽

pp. 466

Author(s):

Herbert Galler ◽

Josefa Luxner ◽

Christian Petternel ◽

Franz F. Reinthaler ◽

Juliana Habib ◽

...

Keyword(s):

Meat Products ◽

Animal Husbandry ◽

Multidrug Resistant ◽

Farm Animals ◽

Resistant Bacteria ◽

Antibiotic Resistant Bacteria ◽

Antibiotic Resistant ◽

E Coli ◽

Multiresistant Bacteria ◽

Vancomycin Resistant

In recent years, antibiotic-resistant bacteria with an impact on human health, such as extended spectrum β-lactamase (ESBL)-containing Enterobacteriaceae, methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant Enterococci (VRE), have become more common in food. This is due to the use of antibiotics in animal husbandry, which leads to the promotion of antibiotic resistance and thus also makes food a source of such resistant bacteria. Most studies dealing with this issue usually focus on the animals or processed food products to examine the antibiotic resistant bacteria. This study investigated the intestine as another main habitat besides the skin for multiresistant bacteria. For this purpose, faeces samples were taken directly from the intestines of swine (n = 71) and broiler (n = 100) during the slaughter process and analysed. All samples were from animals fed in Austria and slaughtered in Austrian slaughterhouses for food production. The samples were examined for the presence of ESBL-producing Enterobacteriaceae, MRSA, MRCoNS and VRE. The resistance genes of the isolated bacteria were detected and sequenced by PCR. Phenotypic ESBL-producing Escherichia coli could be isolated in 10% of broiler casings (10 out of 100) and 43.6% of swine casings (31 out of 71). In line with previous studies, the results of this study showed that CTX-M-1 was the dominant ESBL produced by E. coli from swine (n = 25, 83.3%) and SHV-12 from broilers (n = 13, 81.3%). Overall, the frequency of positive samples with multidrug-resistant bacteria was lower than in most comparable studies focusing on meat products.

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Persulfate mediated solar photo-Fenton aiming at wastewater treatment plant effluent improvement at neutral PH: emerging contaminant removal, disinfection, and elimination of antibiotic-resistant bacteria

Environmental Science and Pollution Research ◽

10.1007/s11356-020-11802-z ◽

2021 ◽

Author(s):

Maria Clara V. M. Starling ◽

Elizângela P. Costa ◽

Felipe A. Souza ◽

Elayne C. Machado ◽

Juliana Calábria de Araujo ◽

...

Keyword(s):

Wastewater Treatment ◽

Wastewater Treatment Plant ◽

Treatment Plant ◽

Resistant Bacteria ◽

Antibiotic Resistant Bacteria ◽

Antibiotic Resistant ◽

E Coli ◽

Effluent Quality ◽

Neutral Ph ◽

Wastewater Treatment Plant Effluent

AbstractThis work investigated an innovative alternative to improve municipal wastewater treatment plant effluent (MWWTP effluent) quality aiming at the removal of contaminants of emerging concern (caffeine, carbendazim, and losartan potassium), and antibiotic-resistant bacteria (ARB), as well as disinfection (E. coli). Persulfate was used as an alternative oxidant in the solar photo-Fenton process (solar/Fe/S2O82−) due to its greater stability in the presence of matrix components. The efficiency of solar/Fe/S2O82− at neutral pH using intermittent iron additions is unprecedented in the literature. At first, solar/Fe/S2O82− was performed in a solar simulator (30 W m−2) leading to more than 60% removal of CECs, and the intermittent iron addition strategy was proved effective. Then, solar/Fe/S2O82− and solar/Fe/H2O2 were compared in semi-pilot scale in a raceway pond reactor (RPR) and a cost analysis was performed. Solar/Fe/S2O82− showed higher efficiencies of removal of target CECs (55%), E. coli (3 log units), and ARB (3 to 4 log units) within 1.9 kJ L−1 of accumulated irradiation compared to solar/Fe/H2O2 (CECs, 49%; E. coli, 2 log units; ARB, 1 to 3 log units in 2.5 kJ L−1). None of the treatments generated acute toxicity upon Allivibrio fischeri. Lower total cost was obtained using S2O82− (0.6 € m−3) compared to H2O2 (1.2 € m−3). Therefore, the iron intermittent addition aligned to the use of persulfate is suitable for MWWTP effluent quality improvement at neutral pH.

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The Antibacterial Potential of Honeydew Honey Produced by Stingless Bee (Heterotrigona itama) against Antibiotic Resistant Bacteria

Antibiotics ◽

10.3390/antibiotics9120871 ◽

2020 ◽

Vol 9 (12) ◽

pp. 871

Author(s):

Wen-Jie Ng ◽

Nam-Weng Sit ◽

Peter Aun-Chuan Ooi ◽

Kah-Yaw Ee ◽

Tuck-Meng Lim

Keyword(s):

Honey Bee ◽

Pathogenic Bacteria ◽

Apis Cerana ◽

Stingless Bee ◽

Morphological Alteration ◽

Resistant Bacteria ◽

Antibacterial Effects ◽

Electron Microscopic ◽

Antibiotic Resistant ◽

E Coli

Scientific studies about the antibacterial effects of honeydew honey produced by the stingless bee are very limited. In this study, the antibacterial activities of 46 blossom and honeydew honeys produced by both honey bees and stingless bees were evaluated and compared. All bacterial isolates showed varying degrees of susceptibility to blossom and honeydew honeys produced by the honey bee (Apis cerana) and stingless bee (Heterotrigona itama and Geniotrigona thoracica) in agar-well diffusion. All stingless bee honeys managed to inhibit all the isolates but only four out of 23 honey bee honeys achieved that. In comparison with Staphylococcus aureus, Escherichia coli was found to be more susceptible to the antibacterial effects of honey. Bactericidal effects of stingless bee honeys on E. coli were determined with the measurement of endotoxins released due to cell lysis. Based on the outcomes, the greatest antibacterial effects were observed in honeydew honey produced by H. itama. Scanning electron microscopic images revealed the morphological alteration and destruction of E. coli due to the action of this honey. The combination of this honey with antibiotics showed synergistic inhibitory effects on E. coli clinical isolates. This study revealed that honeydew honey produced by H. itama stingless bee has promising antibacterial activity against pathogenic bacteria, including antibiotic resistant strains.

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Occurrence and spread of antibiotic-resistant bacteria on animal farms and in their vicinity in Poland and Ukraine—review

Environmental Science and Pollution Research ◽

10.1007/s11356-021-17773-z ◽

2021 ◽

Author(s):

Karolina Jeżak ◽

Anna Kozajda

Keyword(s):

Pathogenic Bacteria ◽

Large Scale ◽

Multidrug Resistant ◽

Animal Origin ◽

Resistant Bacteria ◽

Antibiotic Resistant Bacteria ◽

Antibiotic Resistant ◽

Animal Farming ◽

Food Of Animal Origin ◽

Zoonotic Bacteria

AbstractIntensive animal farming emits to the environment very high concentrations of bioaerosol, mainly composed of microorganisms, including antibiotics resistant strains, and their derivatives. Poland is a significant producer of poultry and swine in Europe; Ukraine is located in the immediate vicinity of Poland and the EU. Thus, the review focuses on the presence of potentially pathogenic and antimicrobial-resistant zoonotic bacteria and antimicrobial genes in the environment of farms and food of animal origin in Poland and Ukraine. Existing data confirms presence of these bacteria in the food animal origin chain environment in both countries. However, it is difficult to compare the scale of multidrug-resistant bacteria (e.g. MRSA, ESBL) dissemination in Poland and Ukraine with other EU countries due to lack of more extensive studies and large-scale monitoring in these two countries. A series of studies concerning resistance of pathogenic bacteria isolated from livestock environment have been published in Poland but usually on single farms with a very limited number of samples, and without a genotypic drug resistance marking. From Ukraine are available only few reports, but also disturbing. The risk of antibiotic-resistant bacteria transmission does not only concern animal farming, but also other facilities of animal origin food supply chains, especially slaughterhouses.

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Detection of Antibiotic-Resistant Bacteria, Resistance Determinants, and Mobile Elements in Surface Waters in Lebanon

10.1101/2021.02.12.21251645 ◽

2021 ◽

Author(s):

Jennifer Moussa ◽

Edmond Abboud ◽

Sima Tokajian

Keyword(s):

Surface Water ◽

Multidrug Resistant ◽

Resistant Bacteria ◽

Population Mobility ◽

Antibiotic Resistant Bacteria ◽

Antibiotic Resistant ◽

E Coli ◽

Resistance Determinants ◽

Bacterial Contaminants ◽

Plasmid Analysis

AbstractThe prevalence of antibiotic-resistant bacteria in surface water in Lebanon is a growing concern and understanding the mechanisms of the spread of resistance determinants is essential. We aimed at studying the occurrence of resistant organisms and determinants in surface water sources in Lebanon and understanding their mobilization and transmission. Water samples were collected from five major rivers in Lebanon. 91 isolates were recovered out of which 25 were multidrug-resistant (MDR) and accordingly were further characterized. Escherichia coli and Klebsiella pneumoniae were the most commonly identified MDR isolates. Conjugation assays coupled with in silico plasmid analysis were performed and validated using PCR-based replicon typing (PBRT) to identify and confirm incompatibility groups and the localization of β-lactamase encoding genes. E. coli EC23 carried a blaNDM-5 gene on a conjugative, multireplicon plasmid, while blaCTX-M-15 and blaTEM-1B were detected in the majority of the MDR isolates. Different ST types were identified including the highly virulent E. coli ST131. Our results showed a common occurrence of bacterial contaminants in surface water and an increase in the risk for the dissemination of resistance determinants exacerbated with the ongoing intensified population mobility in Lebanon and the widespread lack of wastewater treatment.

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Development of Multi-Concentration Ag:Cu Bimetallic Nanoparticles as a Promising Bactericidal for Antibiotic-Resistant Bacteria as Per Molecular Docking Exploration

10.21203/rs.3.rs-115751/v1 ◽

2020 ◽

Author(s):

S. Mureed ◽

S. Naz ◽

A. Haider ◽

A. Raza ◽

A. Ul-Hamid ◽

...

Keyword(s):

Molecular Docking ◽

Biosynthetic Pathway ◽

Bimetallic Nanoparticles ◽

Resistant Bacteria ◽

Antibiotic Resistant Bacteria ◽

Binding Interaction ◽

Antibiotic Resistant ◽

E Coli ◽

Binding Score ◽

Water As Solvent

Abstract The present study is concerned with the influence of various concentrations of Ag within Cu:Ag bimetallic nanoparticles developed for use as a promising anti-bacterial agent against antibiotic-resistant bacteria. Here, Cu:Ag bimetallic nanoparticles (NPs) with various concentration ratios (2.5, 5.0, 7.5, and 10 wt.%) of Ag in fixed amount of Cu labeled as 1:0.025, 1:0.050, 1:0.075, and 1:0.1 were synthesized using co-precipitation method with ammonium hydroxide and deionized water as solvent, polyvinyl pyrrolidone as a capping agent, and sodium borohydride and ascorbic acid as reducing agents. These formulated products were characterized through a variety of techniques. XRD confirmed phase purity and detected the presence of distinct fcc structures belonging to Cu and Ag phases. FTIR spectroscopy confirmed the presence of vibrational modes corresponding to various functional groups and recorded characteristic peak emanating from the bimetallic. UV-visible spectroscopy revealed reduction in band gap with increasing Ag content. SEM and HR-TEM micrographs demonstrated spherical morphology of Ag-doped Cu bimetallic with small and large scale agglomerations. The samples exhibited varying dimensions and interlayer spacings. Bactericidal action of synthesized Cu:Ag bimetallic NPs depicted statistically significant (P < 0.05) inhibition zones recorded for various concentrations of Ag dopant against Staphylococcus aureus (S. aureus), Escherichia coli (E. coli), and Acinetobacter baumannii (A. baumannii) ranging from (0.85 – 2.8 mm), (0.55 – 1.95 mm) and (0.65 – 1.85 mm), respectively. Broadly, Cu:Ag bimetallic NPs were found to be more potent against gram-positive compared with gram-negative. Molecular docking study of Ag-Cu bimetallic NPs was performed against β-lactamase which is a key enzyme of cell wall biosynthetic pathway from both S. aureus (Binding score: -4.981 kcal/mol) and A. bauminnii (Binding score: -4.013 kcal/mol). Similarly, binding interaction analysis against FabI belonging to fatty acid biosynthetic pathway from A. bauminnii (Binding score: -3.385 kcal/mol) and S. aureus (Binding score: -3.012 kcal/mol) along with FabH from E. coli (Binding score: -4.372 kcal/mol) was undertaken. These theoretical computations indicate Cu-Ag bimetallic NPs as possible inhibitor of selected enzymes. It is suggested that exploring in vitro inhibition potential of these materials may open new avenues for antibiotic discovery.

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The occurrence of antibiotic-resistant bacteria, including Escherichia coli, in municipal wastewater and river water

E3S Web of Conferences ◽

10.1051/e3sconf/201910000061 ◽

2019 ◽

Vol 100 ◽

pp. 00061 ◽

Cited By ~ 1

Author(s):

Adriana Osińska ◽

Ewa Korzeniewska ◽

Monika Harnisz ◽

Sebastian Niestępski ◽

Piotr Jachimowicz

Keyword(s):

Escherichia Coli ◽

Wastewater Treatment ◽

River Water ◽

Municipal Wastewater ◽

High Efficiency ◽

Treated Wastewater ◽

Resistant Bacteria ◽

Antibiotic Resistant Bacteria ◽

Antibiotic Resistant ◽

E Coli

Wastewater treatment plants (WWTPs) are major reservoirs of antibiotic-resistant bacteria (ARB) which are transported to the natural environment with discharged effluents. Samples of untreated wastewater (UWW) and treated wastewater (TWW) from four municipal WWTPs and samples of river water collected upstream (URW) and downstream (DRW) from the effluent discharge point were analyzed in the study. The total counts of bacteria resistant to β-lactams and tetracyclines and the counts of antibiotic-resistant Escherichia coli were determined. Antibiotic-resistant bacteria, including antibiotic-resistant E. coli, were removed with up to 99.9% efficiency in the evaluated WWTPs. Despite the above, ARB counts in TWW samples were high at up to 1.25x105 CFU/mL in winter and 1.25x103 CFU/mL in summer. Antibiotic-resistant bacteria were also abundant (up to 103 CFU/ml) in URW and DRW samples collected in winter and summer. In both UWW and TWW samples, the counts of ARB and antibiotic-resistant E. coli were at least one order of magnitude lower in summer than in winter. The study revealed that despite the high efficiency of bacterial removal in the wastewater treatment processes, considerable amounts of ARB are released into the environment with TWW and that the percentage of ARB in total bacterial counts increases after wastewater treatment.

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Lactic acid bacterial bacteriocins and their bioactive properties against food-associated antibiotic-resistant bacteria

Annals of Microbiology ◽

10.1186/s13213-021-01652-6 ◽

2021 ◽

Vol 71 (1) ◽

Author(s):

Emmanuel Edoghogho Imade ◽

Solomon Esharegoma Omonigho ◽

Olubukola Oluranti Babalola ◽

Ben Jesuorsemwen Enagbonma

Keyword(s):

Lactic Acid ◽

Foodborne Pathogens ◽

Food Products ◽

Lactobacillus Fermentum ◽

Resistant Bacteria ◽

Antibiotic Resistant Bacteria ◽

Antibiotic Resistant ◽

E Coli ◽

Agar Well Diffusion Assay ◽

Diffusion Assay

Abstract Purpose Incidence of foodborne diseases and growing resistance of pathogens to classical antibiotics is a major concern in the food industry. Consequently, there is increasing demand for safe foods with fewer chemical additives but natural products which are not harmful to the consumers. Bacteriocins, produced by lactic acid bacteria (LAB), is of interest because they are active in a nanomolar range, do not have toxic effects, and are readily available in fermented food products. Methods In this research, LAB were isolated from fufu, gari, kunu, nono, and ogi using De Mann, Rogosa, and Sharpe agar. Cell-free supernatants were prepared from 18-24 h LAB culture grown on MRS broth. Effect of organic acid was eliminated by adjusting the pH of the supernatants to 7.0 with 1M NaOH while the effect of hydrogen peroxide was eliminated by treating with Catalase enzyme. The supernatant was then filter-sterilized using a membrane filtration unit with a 0.2-μm pore size millipore filter and subjected to agar well diffusion assay against foodborne antibiotic-resistant bacteria. Result A total of 162 isolates were obtained from the food samples. The antimicrobial sensitivity test yielded positive results for 45 LAB isolates against Staphylococcus aureus ATCC 25923 while 52 LAB isolates inhibited Escherichia coli ATCC 25922. On confirmation of the bacteriocinogenic nature of the inhibitory substance, 4 of the LAB isolates displayed a remarkable degree of inhibition to Leuconostoc mesenteroides, Salmonella typhimurium, and Bacillus cereus. Agar well diffusion assay was also performed against antibiotic-resistant foodborne pathogens using the cell-free supernatant (CFS) obtained from Lactobacillus fermentum strain NBRC15885 (Limosilactobacillus fermentum), Lactobacillus fermentum strain CIP102980 (Limosilactobacillus fermentum), Lactobacillus plantarum strain JCM1149 (Lactiplantibacillus garii), and Lactobacillus natensis strain LP33 (Companilactobacillus nantensis). The foodborne pathogens exhibited a notable level of resistance to antibiotics, with B. cereus exhibiting a resistance profile of 40%, S. aureus (50%), K. pnuemoniae (70%), E. coli (60%), and S. typhi (40%). The (CFS) was able to inhibit the growth of B. cereus, Klebsiella pneumonia, S. typhimurium, S. aureus, and E. coli. Conclusion Therefore, it portends that the bacteriocins produced by the LAB isolated from these food products could act as probiotics for effective inhibition of the growth of antibiotic-resistant foodborne pathogens.

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Effect of Sunlight on the Efficacy of Commercial Antibiotics Used in Agriculture

Frontiers in Microbiology ◽

10.3389/fmicb.2021.645175 ◽

2021 ◽

Vol 12 ◽

Author(s):

Sebastian J. Khan ◽

Amanda M. Osborn ◽

Prahathees J. Eswara

Keyword(s):

Animal Husbandry ◽

Citrus Greening ◽

Resistant Bacteria ◽

Disc Diffusion ◽

Antibiotic Resistant Bacteria ◽

Antibiotic Resistant ◽

E Coli ◽

Citrus Greening Disease ◽

Greening Disease ◽

Diffusion Assay

Antibiotic stewardship is of paramount importance to limit the emergence of antibiotic-resistant bacteria in not only hospital settings, but also in animal husbandry, aquaculture, and agricultural sectors. Currently, large quantities of antibiotics are applied to treat agricultural diseases like citrus greening disease (CGD). The two commonly used antibiotics approved for this purpose are streptomycin and oxytetracycline. Although investigations are ongoing to understand how efficient this process is to control the spread of CGD, to our knowledge, there have been no studies that evaluate the effect of environmental factors such as sunlight on the efficacy of the above-mentioned antibiotics. We conducted a simple disc-diffusion assay to study the efficacy of streptomycin and oxytetracycline after exposure to sunlight for 7- or 14-day periods using Escherichia coli and Bacillus subtilis as the representative strains of Gram-negative and Gram-positive organisms, respectively. Freshly prepared discs and discs stored in the dark for 7 or 14 days served as our controls. We show that the antibiotic potential of oxytetracycline exposed to sunlight dramatically decreases over the course of 14 days against both E. coli and B. subtilis. However, the effectiveness of streptomycin was only moderately impacted by sunlight. It is important to note that antibiotics that last longer in the environment may play a deleterious role in the rise and spread of antibiotic-resistant bacteria. Further studies are needed to substantively analyze the safety and efficacy of antibiotics used for broader environmental applications.

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