Mechanisms of Pathogenic Escherichia coli Attachment to Meat.

Escherichia coli are present in the human and animal microbiome as facultative anaerobes and are viewed as an integral part of the whole gastrointestinal environment. In certain circumstances, some species can also become opportunistic pathogens responsible for severe infections in humans. These infections are caused by the enterotoxinogenic E. coli, enteroinvasive E. coli, enteropathogenic E. coli and the enterohemorrhagic E. coli species, frequently present in food products and on food matrices. Severe human infections can be caused by consumption of meat contaminated upon exposure to animal feces, and as such, farm animals are considered to be a natural reservoir. The mechanisms by which these four major species of E. coli adhere and persist in meat postslaughter are of major interest to public health and food processors given their frequent involvement in foodborne outbreaks. This review aims to structure and provide an update on the mechanistic roles of environmental factors, curli, type I and type IV pili on E. coli adherence/interaction with meat postslaughter. Furthermore, we emphasize on the importance of bacterial surface structures, which can be used in designing interventions to enhance food safety and protect public health by reducing the burden of foodborne illnesses.

Hunting Dynamics and Identification of Potentially Pathogenic Bacteria in European Fallow Deer (Dama dama) across Three Hunting Reserves in Western Romania.

The study focused on the hunting practices and potentially pathogenic bacterial species among European fallow deer (Dama dama). Within a five-year period, three hunting grounds from Western Romania were examined. During this period, a total of 1881 deer were hunted, and 240 samples were collected by rectal and nasal swabbing from 120 carcasses. Bacterial strains were identified utilizing bacteriological assays and the Vitek® 2 Compact system. Notably, the Socodor hunting ground exhibited a significant difference in harvesting quotas between the bucks (Group M) and does/yearlings (Group F), favoring the latter. In the Chișineu Criș-Salișteanca hunting ground, a likely correlation in harvesting quotas between the two groups was observed. The identified potentially pathogenic bacteria were Escherichia coli, Salmonella spp., Staphylococcus aureus, Listeria monocytogenes and Enterococcus faecium. These results highlight the importance of effectively managing the deer population and recognize the potential for Dama dama to spread zoonotic pathogens, emphasizing the necessity of adopting a One Health approach and maintaining ongoing surveillance of this game species' population dynamics.

The Behavior of Some Bacterial Strains Isolated from Fallow Deer Compared to Antimicrobial Substances in Western Romania.

(1) Background: The resistance levels of Escherichia coli, Salmonella spp., Pseudomonas spp., Staphylococcus spp., etc., isolated from the nasal cavity and the rectum of Dama dama deer from three hunting grounds in Western Romania were assessed. (2) Methods: The analysis was completed using the diffusimetric method, compliant with CLSI reference standards, and with Vitek-2 (BioMérieux, France), on 240 samples. (3) Results: The results were statistically analyzed (by one-way ANOVA) revealing that in four of the ten E. coli strains isolated from animals, 87.5% (p < 0.001) resistance was found. E. coli strains were resistant to cephalexin (100%); seven strains were resistant to cephalothin and ampicillin; six were resistant to cefquinome and cefoperazone; five were resistant to amoxicillin/clavulanic acid; and four were resistant to ceftiofur. However, E. coli was sensitive to amikacin (100%). The most efficient structures were beta-lactams, amikacin, and imipenem, to which all 47 strains studied (100%) were sensitive, followed by nitrofurantoin, to which 45 strains (95.7%) were sensitive, neomycin, to which 44 strains (93.6%) were sensitive, ceftiofur, to which 43 strains (91.5%) were sensitive, and trimethoprim/sulfamethoxazole and marbofloxacin, to which 42 strains (89.4%) were sensitive. (4) Conclusions: In wild animal populations, where a human presence is frequently reported, including a constant presence of domestic animals, despite the perceived low risk of emerging resistance to antimicrobials, resistance is likely to develop frequently.

Diversity and Antibiotic Resistance Profiles of Listeria monocytogenes Serogroups in Different Food Products from the Transylvania Region of Central Romania.

ABSTRACT: This study used molecular serogrouping to assess the presence and antimicrobial susceptibility profile of Listeria monocytogenes isolates from food products of different animal origin, collected from a county situated in the historical region of Transylvania in central Romania. Seventeen (7.7%) of 221 screened samples were positive for L. monocytogenes; these included 8 (6.2%) of 130 ready-to-eat products (i.e., sausages, ham, and smoked specialties), 6 (12.8%) of 47 raw meat samples (i.e., minced pork, pork organs, and snails), and 3 (6.8%) of 44 dairy samples (i.e., assortment of cheeses). The identified L. monocytogenes serogroups were 1/2a-3a (47.1%), 4b-4d-4e (29.4%), 1/2c-3c (11.8%), and 4a-4c (11.8%). All isolates were resistant to benzylpenicillin and fusidic acid. Resistance was also detected toward oxacillin (88.2%), fosfomycin (82.4%), clindamycin (76.5%), imipenem (52.9%), ciprofloxacin (41.2%), rifampin (41.2%), trimethoprim-sulfamethoxazole (29.4%), and tetracycline (29.4%). On the other hand, all isolates proved susceptible to gentamicin, moxifloxacin, teicoplanin, vancomycin, tigecycline, erythromycin, and linezolid. All tested strains exhibited multidrug resistance, resulting in the expression of a total of 12 resistance profiles. These findings extend the understanding of the spread of an important pathogen in Romanian food products, highlighting a substantial public health issue and medical concern, especially for consumers with a compromised health status.

Phytochemical Profile and Microbiological Activity of Some Plants Belonging to the Fabaceae Family.

This study aimed to investigate the chemical composition and the activity against Staphylococcus aureus (S. aureus) (ATCC 25923), Streptococcus pyogenes (S. pyogenes) (ATCC 19615), Escherichia coli (E. coli) (ATCC 25922), Pseudomonas aeruginosa (P. aeruginosa) (ATCC 27853), Shigella flexneri (S. flexneri) (ATCC 12022), Salmonella typhimurium (S. typhimurium) (ATCC 14028), Haemophillus influenzae (H. influenza) type B (ATCC 10211) and two fungal strains: Candida albicans (C. albicans) (ATCC 10231) and Candida parapsilopsis (C. parapsilopsis) (ATCC 22019) of the extracts obtained from Melilotus officinalis (MO), Coronilla varia (CV); Ononis spinosa (OS) and Robinia pseudoacacia (RP) (Fabaceae), and to identify the chemical compounds responsible for the antimicrobial effect against the tested strains. The extracts were obtained by conventional hydroalcoholic extraction and analyzed in terms of total polyphenols using the spectrophotometric method and by liquid chromatography (LC). The results have shown that the highest polyphenols content was recorded in the RP sample (16.21 mg gallic acid equivalent GAE/g), followed by the CV (15.06 mg GAE/g), the OS (13.17 mg GAE/g), the lowest value being recorded for the MO sample (11.94 mg GAE/g). The antimicrobial testing of plant extracts was carried out using the microdilution method. The most sensitive strains identified were: E. coli, S. typhimurium, P. aeruginosa and S. pyogenes, while protocatechuic acid, gallic acid, caffeic acid, quercetin, rutin, and kaempferol were identified as the chemical compounds responsible for the antibacterial effect. The analysis of the correlation between the chemical composition and the antimicrobial effect proved a moderate (r > 0.5) positive correlation between rosmarinic acid and S. pyogenes (r = 0.526), rosmarinic acid and S. typhimurium (r = 0.568), quercetin and C. albicans (r = 0.553), quercetin and S. pyogenes (r = 0.605). Therefore, it suggested possible antimicrobial activity generated by these chemical components. The results recommend the Fabaceae plants as promising candidates for further research to develop novel natural antimicrobial drugs.

Environmental Occurrence and Antibiotic Susceptibility Profile of Listeria monocytogenes at a Slaughterhouse Raw Processing Plant in Romania.

This survey was conducted to investigate the occurrence and antimicrobial susceptibility of Listeria monocytogenes isolates in the environment of a pig slaughterhouse raw processing plant complex in western Romania. A total of 97 environmental samples from food contact (n = 60) and nonfood contact (n = 37) surfaces were examined with standard methods. The susceptibility of the isolates to 17 antimicrobial agents was determined with the VITEK 2 automated system. Overall, 25 (25.8%) samples were positive for L. monocytogenes , with recovery rates of 23.3% (n = 14) and 29.7% (n = 11) for food contact and nonfood contact surfaces, respectively. All 25 tested isolates were resistant to benzylpenicillin, imipenem, and fusidic acid. Resistance was observed to oxacillin (23 isolates; 92%), fosfomycin (23 isolates; 92%), clindamycin (22 isolates; 88%), rifampin (14 isolates; 56%), trimethoprim-sulfamethoxazole (12 isolates; 48%), tetracycline (11 isolates; 44%), and ciprofloxacin (1 isolate; 4%). No resistance was found to seven tested agents: gentamicin, moxifloxacin, erythromycin, linezolid, teicoplanin, vancomycin, and tigecycline. All tested L. monocytogenes isolates were resistant to four to nine antimicrobial agents. These results indicate a high prevalence of multidrug-resistant L. monocytogenes isolates in this pork-processing environment, providing baseline information for hygienists and public health specialists.

Grafted α-hydroxyphosphonic acids onto polymeric supports: preparation, characterization, and antimicrobial effect.

The paper deals with the preparation and characterization of compounds with antimicrobial activity: α-hydroxyphosphonic acids grafted onto styrene-12%-(15%)-divinylbenzene copolymer. These products proved to have antimicrobial effect against two species of gram-negative bacteria (Escherichia coli and Pseudomonas aeruginosa) and two species of gram-positive bacteria (Staphylococcus aureus and Bacillus cereus) and a species of yeast (Candida albicans). Tests showed the reduction of bacterial load at different time intervals during the 18 h of contact.

Salmonella in raw chicken meat from the Romanian seaside: frequency of isolation and antibiotic resistance.

The purpose of this study was to investigate the occurrence of Salmonella in raw chicken meat samples collected at the Romanian seaside and to evaluate the antimicrobial susceptibility of the isolates. In 2012, 317 chicken meat samples from slaughterhouses (n = 289) and retail markets (n = 28) were evaluated. Overall, 13.2% (42) of the samples contained Salmonella; 12.8% (37) and 17.8% (5) from the chicken carcasses at slaughterhouses and the fresh meat from retail markets, respectively. Eight serotypes of Salmonella enterica subsp. enterica were identified: Infantis (18 isolates), Bredeney (7), Virchow (6), Djugu (4), Grampian (4), Brandenburg (1), Derby (1), and Ruzizi (1). The isolates were resistant to tetracycline (66.6% of isolates), nalidixic acid (64.3%), sulfamethoxazole (64.3%), ciprofloxacin (61.9%), streptomycin (59.5%), trimethoprim (33.3%), ampicillin (9.5%), chloramphenicol (7.1%), and gentamicin (2.4%). No resistance was found to cefotaxime and ceftazidime. Thirty (71.4%) of the 42 tested isolates had multidrug resistance patterns to at least two antimicrobials. This survey highlighted a multidrug-resistant Salmonella contamination rate in raw chicken meat in this area of Romania, which can seriously threaten human health.

Chemical characterization by GC-MS and in vitro activity against Candida albicans of volatile fractions prepared from Artemisia dracunculus, Artemisia abrotanum, Artemisia absinthium and Artemisia vulgaris.

BACKGROUND: A large number of essential oils is reported to have significant activity against Candida albicans. But the different chemical composition influences the degree of their activity. The intention of this study was to investigate the chemical composition and the activity against Candida albicans of volatile oils obtained from Artemisia dracunculus, A. abrotanum, A. absinthium and A. vulgaris (Asteraceae). The aim of the study was to identify new chemical compounds that have effect against C. albicans.The essential oils were obtained by hydrodistillation or extraction with dichloromethane (a new procedure we developed trying to obtain better, more separated compounds) from air dried above ground plant material and analyzed by GC-MS. Additionally commercial essential oils from the same species were tested. The Candida albicans inhibition studies were carried out by the paper disc diffusion method. RESULTS: The essential oils shared common components but presented differences in composition and showed variable antifungal activity. Davanone and derivatives thereof, compounds with silphiperfolane skeleton, estragole, davanone oil, ß-thujone, sabinyl acetate, herniarin, cis-chrysanthenyl acetate, 1,8-cineol, and terpineol were the main components of Artemisia volatiles. CONCLUSIONS: Among the volatile fractions tested those from A. abrotanum containing davanone or silphiperfolane derivatives showed the highest antifungal activity. The in vitro tests revealed that the Artemisia oils are promising candidates for further research to develop novel anti-candida drugs.