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

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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Effect of sunlight on the efficacy of commercial antibiotics used in agriculture

10.1101/2020.07.10.197848 ◽

2020 ◽

Cited By ~ 1

Author(s):

Sebastian Khan ◽

Amanda Osborn ◽

Prahathees J. Eswara

Keyword(s):

Plant Pathogens ◽

Selective Pressure ◽

Animal Husbandry ◽

Resistant Bacteria ◽

Antibiotic Resistant Bacteria ◽

Antibiotic Resistant ◽

E Coli ◽

Citrus Greening Disease ◽

Mode Of Application ◽

Diffusion Assay

ABSTRACTAntibiotic 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.IMPORTANCEAlthough antibiotics have been used for agricultural purposes for decades, due to the rapid rise in antibiotic resistance this usage needs to be revisited. Questions remain on the appropriate mode of application of antibiotics and the actual benefits of using antibiotics for treating the infections caused by plant pathogens, especially for the ones that are intracellular in nature. Here we show that the two commonly used commercial antibiotics, oxytetracycline and streptomycin, lose their efficacy at different rates in the presence of sunlight. While the former loses its potency within days the latter remains active for many days. Thus, oxytetracycline may not be active long enough to produce desired effect and streptomycin may persist in the environment and as a side effect due to its selective pressure, may force the rise of streptomycin-resistant pathogens.

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Lactic Acid Bacterial Bacteriocins and Their Bioactive Properties Against Food Associated Antibiotic Resistant Bacteria

10.21203/rs.3.rs-636841/v1 ◽

2021 ◽

Author(s):

Emmanuel Edoghogho Imade ◽

Solomon Esharegoma Omonigho

Keyword(s):

Lactic Acid ◽

Foodborne Pathogens ◽

Food Products ◽

Food Samples ◽

Fermented Food ◽

Resistant Bacteria ◽

Klebsiella Pneumonia ◽

Chemical Additives ◽

Antibiotic Resistant ◽

Antimicrobial Sensitivity

Abstract Purpose: Incidence of food borne 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 less 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. Result: A total of 162 isolates were obtained from the food samples. Antimicrobial sensitivity test yielded positive result for 45 LAB isolates against Staphylococcus aureus ATCC 25923 while 52 LAB isolates inhibited the growth of 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 using the cell-free supernatant (CFS) obtained from Lactobacillus fermentum strain NBRC15885, Lactobacillus fermentum strain CIP102980, Lactobacillus plantarum strain JCM1149 and Lactobacillus natensis strain LP33. The (CFS) was able to inhibit the growth of B. subtilis, Klebsiella pneumonia, S. typhimurium, S. aureus and E. coli which are foodborne pathogens.Conclusion: It therefore 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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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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Prevalence of Multidrug-Resistant Foodborne Pathogens and Indicator Bacteria from Edible Offal and Muscle Meats in Nashville, Tennessee

Foods ◽

10.3390/foods9091190 ◽

2020 ◽

Vol 9 (9) ◽

pp. 1190

Author(s):

Siqin Liu ◽

Agnes Kilonzo-Nthenge ◽

Samuel N. Nahashon ◽

Bharat Pokharel ◽

Abdullah Ibn Mafiz ◽

...

Keyword(s):

Foodborne Pathogens ◽

Salmonella Enterica ◽

Ground Beef ◽

Multidrug Resistant ◽

Indicator Bacteria ◽

Resistant Bacteria ◽

Antibiotic Resistant ◽

Beef Liver ◽

E Coli ◽

Retail Meats

This study investigated the prevalence of antimicrobial-resistant bacteria in retail edible offal and muscle meats in Nashville, Tennessee. A total of 348 retail meats (160 edible offal and 188 muscle) were analyzed for Salmonella enterica serovar, Campylobacter, Escherichia coli, E. coli O157:H7, and enterococci. Bacteria was identified using biochemical and PCR methods. Salmonella enterica serovar (4.4% and 4.3%), Campylobacter (1.9% and 1.1%), E. coli (79.4% and 89.4%), and enterococci (88.1% and 95.7%) was detected in offal and muscle meats, respectively. Chicken liver (9.7%) was most frequently contaminated with Salmonella enterica serovar, followed by ground chicken (6.9%) and chicken wings (4.2%). No Salmonella enterica serovar was detected in beef liver, beef tripe, and ground beef. The prevalence of Campylobacter was 6.9%, 2.3%, and 1.4% in beef liver, ground beef, and ground chicken, respectively. None of the meats were positive for E. coli O157:H7. Resistance of isolates was significantly (p < 0.05) highest in erythromycin (98.3%; 99.1%), followed by tetracycline (94%; 98.3%), vancomycin (88.8%; 92.2%) as compared to chloramphenicol (43.1%; 53.9%), amoxicillin/clavulanic (43.5%; 45.7%), and ciprofloxacin (45.7%; 55.7%) in offal and muscle meats, respectively. Imipenem showed the lowest resistance (0%; 0.9%). A total of 41 multidrug-resistant patterns were displayed. Edible offal could be a source of antibiotic-resistant bacteria.

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Antibacterial activity of Cathormion umbellatum

Bangladesh Journal of Pharmacology ◽

10.3329/bjp.v16i3.53420 ◽

2021 ◽

Vol 16 (3) ◽

pp. 91-95

Author(s):

Surachai Rattanasuk ◽

Rujirek Boongapim ◽

Tannatorn Phiwthong

Keyword(s):

Antibacterial Activity ◽

Inhibitory Concentration ◽

Minimum Bactericidal Concentration ◽

Antibacterial Effect ◽

Colorimetric Assay ◽

Inhibition Zone ◽

Resistant Bacteria ◽

Antibiotic Resistant Bacteria ◽

Antibiotic Resistant ◽

Diffusion Assay

The aim of this study was to determine the antibacterial activity of Cathormion umbellatum extracts against seven antibiotic-resistant bacteria. The pods, leaves and branches of C. umbellatum were extracted with ethanol and methanol. The disc diffusion assay was used to screen the antibacterial activity and broth microdilution and colorimetric assay were used to measure the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) values. The result indicated that the highest inhibition zone (11 mm) was presented in ethanolic pods extract against multidrug resistance Klebsiella pneumoniae. The lowest MIC value of 0.05 mg/mL was obtained from branch extracted with ethanol against colistin resistant Pseudomonas aeruginosa. The lowest MBC values of 1.56 mg/mL were obtained when using C. umbellatum leaves extracted with methanol against all test antibiotic-resistant bacteria. This is the first report presented C. umbellatum extracts have the potential to eliminate antibiotic-resistant bacteria in patients. These findings show the antibacterial effect of C. umbellatum.

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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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