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Vibrio cholerae is one of the important human pathogens that is transmitted through contaminated water and food. In Qom province, due to special weather conditions, diseases caused by V. cholerae are endemic. The aim of this study was the prevalence of V. cholerae in water and vegetables of Qom province and the presence of virulence genes. During two years (2020 -2021), 120 samples of agricultural water (70) and vegetables (50) in Qom province were collected. The samples were cultured on specific media. Suspicious colonies were evaluated by Gram staining and biochemical tests and the serotype V. cholerae was identified by serology test. Finally, Then, the presence of virulence genes was investigated by PCR method and also the antibiotic resistance pattern by disk diffusion method was evaluated in the isolates. V. cholerae bacteria were isolated from 17 samples (16.14%), all of which were non -O1. The rate of contamination of water and vegetables was 28.14% (10 cases) and 14.00% (7 cases), respectively. In molecular evaluation, the abundance of virulence genes including: toxR (88.32%), rtxA (58.82%), hlyA (47.05%), chxA (5.88%), and 100% of isolates did not have ctxA, ace and tcpA genes. The most antibiotic resistance is related to ampicillin and amoxicillin (34.29%), followed by cefuroxime (17.46%), imipenem (11.76%), and cefoxitin and trimethoprim -sulfamethoxazole (5.88%). The results of this study showed that V. cholerae non -O1 is present in water and vegetables of Qom province, and as an important source of disease for humans therefore, continuous health monitoring of water and vegetables and proper disinfection of these foods is very important. [ABSTRACT FROM AUTHOR]

Background: Staphylococcus aureus (S. aureus) is responsible for most cases of food poisoning all around the world. The carriers and manipulated foodstuffs are the main sources of bacteria transmission to ready-to-eat food. This study aims to determine the genetic affinity of methicillin-resistant Staphylococcus aureus (MRSA) strains isolated from cream pastries and workers, nasal of Shiraz city confectioneries. Methods: 30 MRSA strains (7 nasal carriers, 23 food isolates) were selected from the bank of bacteria at Shiraz medical faculty. To determine the genetic affinity of the isolates, RAPD-PCR technique was performed using OLP6, OLP11, and OLP13 primers. RAPD-PCR patterns were analyzed using the software GelJ. Results: By using primer OLP6 only 5 RAPD-PCR patterns were produced from DNA ampliqons of creamy pastry isolates and were not enough to compare the genetic affinity of all the isolates. Based on 100% similarity, OLP13 primer produced 20 different patterns with some bands in the range of 1 to 11, and the OLP11 primer produced 22 patterns with some bands from 3 to 11 bands. At closely and possibly genetically related levels, the isolates are categorized into (13-15) and (1-5) clusters. In general, all the isolates are classified into human and food isolates. Conclusions: There was no genetic affinity of MRSA isolates regarding human and food samples; but, a high percentage of close genetic relationship between the isolates increases the possibility of bacteria transfer from humans to pastries and food poisoning. [ABSTRACT FROM AUTHOR]

Background and Objectives: Escherichia coli O157: H7 is one of the most important causes of hemorrhagic colitis, and hemolytic uremic syndrome. The present study aimed to isolate E. coli O157: H7 from foods and patients with hemorrhagic colitis, and identify Shiga toxin genes, phylogenetic comparison, and antibiotic resistance of the isolates. Materials and Methods: In total 400 samples, including patients stool and food were taken in Isfahan-Iran province. Phenotypic tests and PCR were performed to identify Shiga toxin-producing E. coli. The isolated strains were compared phylogenetically by PFGE. Agar disk diffusion was performed to identify the antibiotic resistance of the isolates. Results: Totally, 5 isolates of fecal samples were E. coli O157, but only 2 isolates carried H7 gene. Also, 9 isolates of E. coli O157 were isolated from food samples that 3 isolates were E. coli O157: H7. The isolates carried stx1, stx2, hlyA and eaeA genes. Also, E. coli non-O157: H7 identified from samples that contained stx1, stx2, hlyA genes. The highest susceptibility to imipenem and the highest resistance to ampicillin and ciprofloxacin were observed. There was a similarity of 100% between the E. coli O157: H7 strains isolated from patients and raw milk and minced beef samples. Conclusion: Serotypes other than the O157 of E. coli are more prevalent in patients and food. The E. coli O157: H7 isolates from patients had 100% genetic similarity with minced meat and cow milk isolates, which indicates cattle are the most important reservoir of this bacterium in Iran. [ABSTRACT FROM AUTHOR]

Introduction: Cryptosporidium infection, which has been identified as a major cause of outbreaks of food and waterborne diseases, has raised public health concerns in developed and developing countries. In the present study, the prevalence and risk factors of cryptosporidium in diarrheal children in urban and rural communities of Chaharmahal and Bakhtiari province were investigated. Materials and Methods: A total of 400 samples were randomly collected from the feces of children with diarrhea referred to Shahrekord hospitals and medical diagnostic laboratories. Stool samples were taken from the patients and part of the sample was frozen for the PCR test and part was used for modified Ziehl Neelsen staining. Samples in which cryptosporidium contamination was considered positive in terms of microscopy were also evaluated by the PCR test to determine the parasites species. Results: The prevalence of Cryptosporidium in the collected samples was 3.5%. The results also showed that 85% of children with cryptosporidiosis were under 6 years old and only 15% of patients were between 6 and 12 years old (P <0.05). According to the results, the prevalence of Cryptosporidium was 5% in rural areas and 2% in urban areas (P <0.05). Also, 95% of infected villagers and 85% of infected urban children had contact with animals (P <0.05). The results showed that the prevalence was higher in spring and summer than in cold seasons (P <0.05). But the results revealed that there was no statistically significant difference between males and females affected (P> 0.05). The PCR test results showed that all positive samples were Cryptosporidium parvum. Discussion and Conclusion: Cryptosporidium parvum is the predominant species in Chaharmahal and Bakhtiari province, which is more prevalent in children under 6 years old, in warm seasons and rural areas, and in people who have more contact with animals. [ABSTRACT FROM AUTHOR]

Background and aims: Using iron as a food additive usually causes undesirable sensory changes and side effects in humans. In this study, we made iron (Fe) nanoparticles (NPs) and studied the cytotoxicity of FeSO4 bulk and NPs on HT-29 cells and different doses of these particles on rat intestine. Methods: Particle size of nanoscale was achieved by mechanical technique. Iron particles were characterized using scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The effect of iron particles with different concentrations (6.25, 3.125, and 1.57 mM/mL) on the colon cell line was performed using the MTT assay at 24, 48, and 72 hours. Apoptosis and necrosis of the cells were assessed using Annexin V-FITC staining and propidium iodide (PI) at 24 h. In an in vivo study, Taftoon bread was produced from fortified wheat flour with FeSO4 bulk and NPs, which are recommended in human diet (9, 18, and 27 mg of elemental iron/kg flour). Wistar rats were fed daily with fortified bread for 21 days and their colon and small intestine were then evaluated histopathologically. Statistical analyses were performed using SPSS 22.0 software by chi-square test. Results: The synthesized FeSO4 NPs were smaller than 100 nm, and they had more adverse effects on the viability of the HT-29 cells compared to the bulk- FeSO4 at 72 hours. Flow cytometric study showed that the early apoptosis of cells by the bulk form was more than the NPs, but at the low concentration (1.57 mM/mL), the NPs induced more necrosis than the bulk particles (P=0.063). The survival rate of cells facing all concentrations of NPs and bulk- FeSO4 decreased dose dependently (P=0.075). In vivo results revealed that there were no pathological changes in rats’ intestinal tissues. Conclusion: The bulk and NPs of iron have adverse effects on the HT-29 cells, but no histopathological changes were seen on rats’ intestinal cells. [ABSTRACT FROM AUTHOR]

Introduction: Shiga Toxin-producing Escherichia coli (STEC) is an important organism known as an emerging zoonotic microorganism causing diseases such as hemorrhagic colitis and Hemolytic Uremic Syndrome (HUS) as well as thrombotic thrombocytopenia in humans. This study aimed to determine the contamination of meat-contact surfaces to STEC and the characterization of the virulence genes of the isolates. Materials and Methods: Totally, 111 swab samples were obtained from meat-contact surfaces in slaughterhouses and meat supply centers for 6 months. After the primary enrichment and cultivation on EMB and SMAC environments, sorbitol negative colonies were transferred to differential media and confirmed by specific tests as Escherichia coli. Suspected colonies were evaluated by PCR method to determine the existence of serotype O157: H7 and virulence genes such as Stx1, Stx2, eae, and Hly. Results: E. coli O157 was detected in 14 samples (12.61%), and only 2 isolates (1.8%) were identified as E.coli O157: H7. In PCR, 4 isolates contained Stx1, Stx2, and Hly genes, 2 isolates contained Stx1, eae and Hly genes, 3 isolates contained Stx1 and Hly genes, 1 isolate contained Stx2 and eae genes, 3 isolates contained the Hly gene and 1 isolate did not have any of the virulence genes. Discussion and Conclusion: Concerning the possibility of the transmission of pathogens such as E.coli O157: H7 from contaminated surfaces to carcasses and healthy meat, the lack of attention to the health and care of slaughterhouses and meat supply centers can be concerns for the public health. [ABSTRACT FROM AUTHOR]

BACKGROUND: Antibiotics are widely used for the treatment of livestock. Their inappropriate usage leads to various disorders in humans as a result of consuming animal products. Milk is among the foods that are significantly affected by consuming antibiotics. OBJECTIVES: The objective of this study was to compare Yoghurt Culture Test (YCT), Four- Plate Test (FPT), and the Copan test for detecting antibiotic residues in raw and pasteurized milk produced in Chaharmahal and Bakhtiari province, Iran. METHODS: A total of 146 raw milk samples and 54 pasteurized milk samples were selected randomly from dairy farms and dairy products suppliers. The presence of antibiotics was evaluated by YCT, FPT, and Copan test. In addition, the sensitivity of the three tests for tetracycline and penicillin, as the two common antibiotics in the treatment of animals, was compared. RESULTS: Our findings showed that 8.9% of raw milk and 11% of pasteurized milk samples contained antibiotics. However, the levels of antibiotic residues were higher in 2% of the positive samples than maximum residue levels (MRL). Moreover, significant differences were observed between FPT, YCT, and the Copan test (P<0.05). On the other hand, the positive results of YCT and Copan tests were not significantly different (P>0.05). CONCLUSIONS: The results of this study showed that a low percentage of milk samples contained antibiotic residues higher than the permissible limit. Furthermore, YCT could be used as an inexpensive, easy, and sensitive method for identifying the residues of penicillin and tetracycline in milk. [ABSTRACT FROM AUTHOR]

Background and Objectives: Enterohemorrhagic Escherichia coli (EHEC) causes bloody and non-bloody diarrhea, intestinal infection and extraintestinal complications in humans. This study aimed to isolate and evaluate the prevalence of E. coli O157: H7 and other Shiga toxin-producing E. coli (STEC) and identify the virulence genes (stx1, stx2, hly and eaeA) from patients with diarrhea. Also, the antibiotic resistance profile of the isolated strains was evaluated. Materials and Methods: A total of 100 stool samples were collected from patients with acute diarrhea referring to the hospital and clinics in Isfahan County, Iran. Phenotypic tests and PCR assay were used for detection of E. coli O157: H7 and other Shiga toxin-producing E. coli. The presence of virulence genes (stx1, stx2, hly and eaeA) were identified by PCR. The antibiotic resistance profile of the isolates was determined using the agar disk diffusion method. The results were analyzed descriptively by Sigma stat version 4 software. Results: Seventy - eight out of 100 samples (78%) were contaminated with E. coli. E. coli O157 was isolated from five samples (6.4%), of which only two strains (2.56%) were identified as E. coli O157: H7. According to the results, out of two E. coli O157: H7 isolates, one (50%) isolate contained eaeA and two isolates (100%) contained Stx1, Stx2, hlyA genes. Out of three (3.84%) E. coli O157: HN, one of the isolate (33.3%) contained stx1 and, two isolates (66.7%) were positive for hlyA genes. Also, the results revealed that six strains (7.69%) were non-O157: H7 STEC, of which two isolates (33.3%) contained stx1 and four isolates (66.7%) were positive for stx2 and hlyA genes. The results of antibiogram tests revealed that all of the STEC isolates (100%) were sensitive to imipenem followed by kanamycin, gentamicin and nitrofurantoin (91%). High resistance (54.5%) to ampicillin and ciprofloxacin was observed among the STEC isolates. Conclusion: The results of the current study showed that although the prevalence of E. coli O157: H7 was low among patients with diarrhea, the other STEC strains with relative resistance to antibiotics are more prevalent. [ABSTRACT FROM AUTHOR]

BACKGROUND: Using plastic compounds in food packaging industry creates a lot of problems for the environment. Edible coatings are biodegradable and can control the microbiological and chemical properties of foods. Using herbal essential oils improves the properties of coatings due to their antioxidants and antimicrobial specifications. OBJECTIVES: In this study the effect of potato starch edible coating containing Ziziphora clinopodioides and Thymus daenensis essential oils on chemical and sensory characteristics of refrigerated chicken breast, was evaluated. METHODS: The chicken breast was coated with potato starch containing 0, 0.5 and 1% concentrations of essential oils. Chemical (pH, TVN, TBARs) and sensory tests were performed on days 0, 3, 6, 9 and 12 on different samples stored at 4 °C. Statistical analysis was performed by SPSS software 22 using ANOWA and Nonparametric Kruskal Wallis tests. RESULTS: Treatments with different concentrations of essential oil showed lower values of pH, Thiobarbituric Acid (TBARs) and Total Volatile Nitrogen (TVN) compared to the control samples (P<0.05). CONCLUSIONS: Coating with potato starch enriched with different amounts of essential oils, has a preventive effect on chemical degradation. Essential oils with the concentration of 0.5% can be an optimal dose for improving the sensorial properties of chicken breast. [ABSTRACT FROM AUTHOR]

Introduction: Human gastrointestinal disease caused by verotoxigenic Escherichia coli has been diagnosed for recent decades. Escherichia coli O157:H7 is the most important serotype of verotoxigenic Escherichia coli that cause hemolytic uremic syndrome and hemorrhagic colitis in humans. This study was conducted to determine the occurrence of verotoxigenic E. coli and antibiotic resistance of the isolates from vegetables. Materials and methods: A total of 500 fresh vegetable samples were collected randomly from retail shops in Shahrekord, Iran. E. coli was isolated and identified using bacteriological and biochemical tests. PCR method was used to identify the rbfE, stx1, stx2 and eae genes. Also, antibiotic resistance of the isolates was determined by disk diffusion method. Results: The results represented that among 25 isolates possess virulence genes, 40, 12 and 4% of the isolates contained eaeA, STx2, and both genes, respectively. But none of them contained H7, STx1, and rfbE genes. The antibiotic resistance pattern demonstrated that the isolates were highly resistant to Gentamycin and cefotoxime. Discussion and conclusion: The results of this study showed that the presence of verotoxigenic E.coli in vegetables; and high resistance of the isolates to antibiotics could be hazardous for public health. [ABSTRACT FROM AUTHOR]

Introduction: This study was to determine the prevalence of verotoxigenic E.coli and their virulence factors isolated from coldwater fishes (Rainbow trout) using multiplex PCR. Materials and methods: A total of 100 samples of feces and skins were collected at the final step of production in the production pools. Bacteriological and biochemical examination were done for isolation and confirmation that the isolates belonged to the E.coli species. Multiplex PCR were used to identifying the Stx1, Stx2, eae and hly genes. Results: The results showed that none of the isolates was E.coli O157: H7, but other non-O157 verotoxigenic strains were isolated. Totally 14% of the skin isolates and 4% of fecal isolates contain Stx1, Stx2, eae genes. Discussion and conclusion: The results of this study revealed that the Rainbow trout meat may play a role as a vehicle to transmit the verotoxigenic E.coli to human. Water may contaminate with feces of animals, birds, contaminated fish foods and workers. Controlling the contaminating ones is recommended. [ABSTRACT FROM AUTHOR]

The aim of this study was to determine the occurrence of enterotoxigenic and enteroaggregative Escherichia coli strains and antibiotic resistance of the isolates in raw milk and unpasteurized cheese. Out of 200 samples of raw milk and 50 samples of unpasteurized cheeses, 96 and 24 strains of E. coli were isolated, respectively. Polymerase chain reaction (PCR) was used to detect the genes encoding heat-stable enterotoxin a (STa), heat-stable enterotoxin b (STb), heat labile toxin (LT) and enteroaggregative heat-stable toxin1 (EAST1). Twelve out of 120 (10.00%) isolates harbored the gene for EAST1, 2(1.66%) isolates were detected as producing STb and LT toxins and 12 (10.00%) strains contained STb and EAST1 genes. None of the strains contain the STa gene. All of the strains were tested for antibiotic resistance by disk diffusion method. Disks included: ciprofloxacin (CFN), trimetoprim-sulfamethoxazole (TSX), oxytetracycline (OTC), gentamicin (GMN), cephalexin (CPN), nalidixic acid (NDA) and nitrofurantoin (NFN), ampicillin (AMP), neomycin (NEO) and streptomycin (STM). Among 120 isolated strains of E. coli, the resistance to each antibiotics were as follows: OTC100%, CPN 86.00%, NDA 56.00%, NFN 42.00%, GMN 30.00%, TSX 28.00%, CFN 20%, AM 23.40% and STM 4.25%. None of the isolates were resistant to NEO. The present data indicate that different resistant E. coli pathogens may be found in raw milk and unpasteurized cheese. It poses an infection risk for human and transferring the resistant factors to microflora of the consumers gut.