Urinary tract infection is one of the last diseases prevalent in humans, with various causative agents affecting 250 million people annually, This study analyzed UTIs in Iraqi patients caused by
...Escherichia coli
. ESBL enzymes contribute to antibiotic resistance. The research aimed to analyze ESBL gene frequency, resistance patterns, and genetic diversity of
E. coli
strains; Between Dec 2020 and May 2021, 200 urine samples were collected, cultured on blood agar, EMB, and MacConkey's plates, samples incubated at 37 °C for 24 h. Positive samples (> 100 cfu/ml) underwent Kirby-Bauer and CLSI antibiotic susceptibility testing. PCR detected virulence genes, Beta-lactamase coding genes, and biofilm-associated resistance genes in
E. coli
isolates; Out of 200 isolates, 80% comprised Gram-positive and Gram-negative bacteria. Specifically, 120 isolates (60%) were Gram-negative, while 40 isolates (20%) were Gram-positive. Among Gram-negative isolates, 20% were identified as
E. coli
. Remarkably, all
E. coli
strains showed resistance to all tested antibiotics, ranging from 80 to 95% resistance. The
E. coli
isolates harbored three identified resistance genes: blaTEM, blaSHV, and blaCTXM. Regarding biofilm production, 10% showed no formation, 12% weak formation, 62% moderate formation, and 16% strong formation; our study found that pathogenic
E. coli
caused 20% of UTIs. The majority of studied
E. coli
strains from UTI patients carried the identified virulence genes, which are vital for infection development and persistence.
group is widespread in nature and foods. Several members of this group are recognized as causing food spoilage and/or health issues. This study was designed to determine the prevalence and genetic ...diversity of the
group strains isolated in Tunisia from different foods (cereals, spices, cooked food, fresh-cut vegetables, raw and cooked poultry meats, seafood, canned, pastry, and dairy products). In total, 687 different samples were collected and searched for the presence of the
group after selective plating on MYP agar and enumeration of each sample. The typical pink-orange uniform colonies surrounded by a zone of precipitate were assumed to belong to the
group. One typical colony from each sample was subcultured and preserved as cryoculture. Overall, 191 (27.8%) food samples were found positive, giving rise to a collection of 191
-like isolates. The concentration of
-like bacteria were below 10
cfu/g or ml in 77.5% of the tested samples. Higher counts (>10
cfu/g or ml) were found in 6.8% of samples including fresh-cut vegetables, cooked foods, cereals, and pastry products. To verify whether
-like isolates belonged to the
group, a PCR test targeting the
gene sequence specific of the group was carried out. Therefore, 174 isolates were found to be positive. Food samples were contaminated as follows: cereals (67.6%), pastry products (46.2%), cooked food (40.8%), cooked poultry meat (32.7%), seafood products (32.3%), spices (28.8%), canned products (16.7%), raw poultry meat (9.4%), fresh-cut vegetables (5.0%), and dairy products (4.8%). The 174
isolates were characterized by partial sequencing of the
gene, using a Sym'Previous software tool to assign them to different phylogenetic groups. Strains were distributed as follows: 61.3, 29.5, 7.5, and 1.7% in the group III, IV, II, and V, respectively. The genetic diversity was further assessed by ERIC-PCR and PFGE typing methods. PFGE and ERIC-PCR patterns analysis allowed discriminating 143 and 99 different profiles, respectivey. These findings, associated to a relatively higher prevalence of
group in different foods, could be a significant etiological agent of food in Tunisia.
Despite the importance of the B. cereus group as major foodborne pathogens that may cause diarrheal and/or emetic syndrome(s), no study in Tunisia has been conducted in order to characterize the ...pathogenic potential of the B. cereus group. The aim of this study was to assess the sanitary potential risks of 174 B. cereus group strains isolated from different foodstuffs by detecting and profiling virulence genes (hblA, hblB, hblC, hblD, nheA, nheB, nheC, cytK, bceT and ces), testing the isolates cytotoxic activity on Caco-2 cells and antimicrobial susceptibility towards 11 antibiotics.
The entertoxin genes detected among B. cereus isolates were, in decreasing order, nheA (98.9%), nheC (97.7%) and nheB (86.8%) versus hblC (54.6%), hblD (54.6%), hblA (29.9%) and hblB (14.9%), respectively encoding for Non-hemolytic enterotoxin (NHE) and Hemolysin BL (HBL). The isolates are multi-toxigenic, harbouring at least one gene of each NHE and HBL complexes associated or not to bceT, cytK-2 and ces genes. Based on the incidence of virulence genes, the strains were separated into 12 toxigenic groups. Isolates positive for cytK (37,9%) harbored the cytK-2 variant. The detection rates of bceT and ces genes were 50.6 and 4%, respectively. When bacteria were incubated in BHI-YE at 30 °C for 18 h and for 5 d, 70.7 and 35% of the strains were shown to be cytotoxic to Caco-2 cells, respectively. The cytotoxicity of B. cereus strains depended on the food source of isolation. The presence of virulence factors is not always consistent with cytotoxicity. However, different combinations of enterotoxin genetic determinants are significantly associated to the cytotoxic potential of the bacteria. All strains were fully sensitive to rifampicin, chloramphenicol, ciprofloxacin, and gentamycin. The majority of the isolates were susceptible to streptomycin, kanamycin, erythromycin, vancomycin and tetracycline but showed resistance to ampicillin and novobiocin.
Our results contribute data that are primary to facilitate risk assessments in order to prevent food poisoning due to B. cereus group.
E. coli responsible for urinary tract infections (UTI) became resistant to obtainable therapies. So, nanotechnology appears currently as promising innovation among various strategies under ...development. In the present study we evaluate the antimicrobial effects of CuO and ZnO nanoparticles against E. coli isolated from UTI. Biofilm production and expression of quorum sensing genes luxS and motA were performed on E. coli treated with the nanoparticles. luxS and motA genes were detected in the tested E. coli. All isolates produced strong, moderate and weak biofilm. All isolates had a weak biofilm formation and decreased gene expression for luxS and motA genes after treatment with CuO, ZnO and their mixture. Besides, CuO and ZnO had non-toxic effects on Human Dermal Fibroblasts and neonatal normal cells. In conclusion, the mixture of CuO and ZnO had a role in decreasing the gene expression of luxS and motA genes more than each alone.
A combined enrichment/ newly developed
TaqMan
real-time PCR (qPCR) method as a screening assay to detect
spp. in 500 naturally food matrices is evaluated. DNA template for qPCR was extracted from an ...overnight pre-enriched sample in buffered peptone water using lysis-guanidine isothiocyanate method. Heterologous internal amplification control (IAC) was incorporated during qPCR assays and co-amplified with the
gene of the target pathogen.
qPCR exhibited 100% specificity when testing 94
strains (inclusivity) and 32 non-
strains (exclusivity). The qPCR showed a consistent detection of two copies of the
gene/PCR reaction, a good intra- and inter-run reproducibility with a good PCR efficiency (89.6%). QPCR was sensitive and showed
detection at 8.5 × 10
CFU mL
of artificially spiked poultry meat -BWP solution in less than 40 cycles. When analyzing 500 different food matrices and comparing the results with the ISO 6579:2002 conventional culture method, the sensitivity and specificity were 100 and 76.6%, respectively. QPCR showed
spp. DNA in raw poultry meat 27/45 (60%), milk 31/93 (33.3%), raw red meat 5/13 (38.5%), and fish 11/46 (23.9%) samples. The prevalence of
spp. in cakes, dairy, cooked meals, charcuterie products using qPCR was 11/14 (26.8%), 5/22 (22.7%), 32/150 (21.3%), and 5/20 (25%), respectively, compared to 0% as demonstrated by culture.
Anatum was the most common serovar found associated with red meat compared to
kentucky isolated from fish and poultry meat. In conclusion, our study is the first to use a combined enrichment/
qPCR method as a screening assay to detect
DNA in different types of commercialized food in Southern Tunisia. QPCR results indicate that
contamination is common in milk and in other types of food samples.
A AuNP-modified screen-printed carbon electrode (AuNP/SPCE) for monitoring important biomolecules, such as dopamine (DA) and riboflavin (RF), having a high potential for personalized medicine and for ...continuous monitoring of human health is here proposed. AuNPs were synthesized using the extract of Rhanterium suaveolens as a reducing medium and were characterized by UV–vis spectroscopy, dynamic light scattering (DLS), and scanning and transmission electron microscopy (SEM and TEM). The synthesized AuNPs appear spherical and present a bimodal size distribution with a maximum centered at around 30–50 nm. Cyclic voltammetry (CV) experiments demonstrated that the modified AuNP/SPCE sensor exhibits superior electrochemical performances to the bare SPCE. Low limits of detection (LODs) of 0.2 and 0.07 μM at S/N = 3 and sensitivities of 550.4 and 2399 μA mM–1 cm–2 were registered for DA and RF detection, respectively. Results demonstrate the promising electrochemical characteristics of the synthesized AuNPs and developed AuNP/SPCE electrochemical sensor for the determination of these important biomolecules.
Following the ban on the use of growth factors, the use of zeolite in poultry feed could be a solution to obtain healthier food products that are more demanded by the consumer.
Zeolite ...(Clinoptilolite) was added to turkey male and female feed at concentrations 1% or 2% and was evaluated for its effectiveness on performance of the production. The turkeys were given free and continuous access to a nutritionally non-limiting diet (in meal form) that was either a basal diet or a 'Zeolite supplemented-diet' (the basal diet supplemented with clinoptilolite at a level of 1% or 2%).
It was found that adding zeolite in the turkey diet had a positive effect on growth performance and increased weight gain compared to the control. In addition, zeolite treatment had a positive effect on oxidative stress and organoleptic parameters that were measured. It was found that adding zeolite in the turkey diet reduced the MDA level in the liver and in the meat, as compared to the control. Quality of meat was measured as a significantly increase (p < 0.05) in pH for male meat, indicated that the zeolite could maintain the quality of longer period. The adding of zeolite in the turkey diet increased level of polyunsaturated fatty acid.
This study showed the significance of using zeolite, as a feed additive for turkey, as part of a comprehensive program to improve growth performance and oxidative stress parameters and to increase level of polyunsaturated fatty acid on the turkey body.
Escherichia coli is considered one of the uropathogenic bacteria with different infection symptoms representing mild illness to acute sepsis. This study aims to detect E. coli in patients with ...urinary infection and investigate quorum sensing genes (lux S and motA) in multi-drug resistant isolates of E. coli. 200 urine samples were collected from patients with urinary tract infections from several hospitals in Baghdad. The antibiotics sensitivity test showed high resistance of isolates for Ampicillin (100%), Cefazolin (97%), Trimethoprim/ Sulfamethoxazole (83%), Ceftriaxone (77%), Ceftazidime and Ciprofloxacin (70% each of them), and moderate resistance of isolates for Levofloxacin (50%), Gentamicin (47%), Cefepime (40%), while low resistance Piperacillin/ Tazobactam (33%), Cefoxitin (30%), Nitrofurantoin (17%), Imipenem (10%), Ertapenem and Amikacin (7% each of them), and Tigecycline (3%). The results showed an increase percentage of infection in females was 30% in the ages 30-44 years, whereas in ages 15-29 and more than 45 years was 17%. There was a high percentage (57.11%) of resistant isolates in females which are ages 30-44 years. While the ages more than 45 years were 66.4% and ages 15-29 were 34%. While, in males, the percentage was high in ages more than 45 years (35.25%) followed by age groups 30-44 years (31.5%) and 15-29 years (31%). The prevalence percentage for luxS and motA genes in E. coli was 100%. In conclusion, E. coli isolates were multi-drug resistant due to all isolates had quorum sensing genes. Moreover, uropathogenic of E. coli in females was more frequent than in males due to the resistance of bacteria to antibiotics.
Bovine abortion of unknown infectious etiology still remains a major economic problem. Thus, we investigated whether Brucella spp., Listeria monocytogenes, Salmonella spp., Campylobacter spp. and ...Coxiella burnetii are associated with abortion and/or stillbirth in Tunisian dairy cattle. Using a pan-Chlamydiales PCR, we also investigated the role of Chlamydiaceae, Waddlia chondrophila, Parachlamydia acanthamoebae and other members of the Chlamydiales order in this setting. Veterinary samples taken from mid to late-term abortions from twenty dairy herds were tested. From a total of 150 abortion cases collected, infectious agents were detected by PCR in 73 (48.66%) cases, 13 (8.66%) of which represented co-infections with two infectious agents. Detected pathogens include Brucella spp (31.3%), Chlamydiaceae (4.66%), Waddlia chondrophila (8%), Parachlamydia acanthamoebae (5.33%), Listeria monocytogenes (4.66%) and Salmonella spp. (3.33%). In contrast, Campylobacter spp. and Coxiella burnetii DNA were not detected among the investigated veterinary samples. This demonstrates that different bacterial agents may cause bovine abortion in Tunisia. This is the first report suggesting the role of Parachlamydia acanthamoebae in bovine abortion in Africa. Further studies with a larger number of samples are necessary to confirm whether this emerging pathogen is directly linked to abortion in cattle.
In 2017-2018, extensive symptoms of sudden decline and fruit rot were observed on date palms in southern Tunisia. Samples of diseased plants were randomly collected in six localities. Based on ...morphological identification,
was the most frequent fungal genus detected. A sequencing of translation elongation factor, calmodulin, and second largest subunit of RNA polymerase II genes was used to identify 63 representative
strains at species level and investigate their phylogenetic relationships. The main species detected was
, and at a much lesser extent,
,
,
,
and
. Pathogenicity on the
variety plantlets and the capability to produce mycotoxins were also assessed. All
species were pathogenic complying Koch's postulates.
strains produced mainly fumonisins (FBs), beauvericin (BEA), and, to a lesser extent, enniatins (ENNs) and moniliformin (MON). All
strains produced low levels of BEA, diacetoxyscirpenol, and neosolaniol; two strains produced also T-2 toxin, and a single strain produced HT-2 toxin.
,
,
produced only BEA.
strains produced MON, BEA, and ENNs. This work reports for the first time a comprehensive multidisciplinary study of
species on date palms, concerning both phytopathological and food safety issues.
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