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Öğe A Molecular Investigation of Carbapenem Resistant Enterobacteriaceae and blaKPC, blaNDM and blaOXA-48 Genes in Raw Milk(Kafkas Univ, Veteriner Fakultesi Dergisi, 2020) Al, Serhat; Hizlisoy, Harun; Ertas Onmaz, Nurhan; Karadal, Fulden; Barel, Mukaddes; Yildirim, Yeliz; Gonulalan, ZaferThe success of antibiotic treatment has been negatively affected due to developing and spreading antimicrobial resistance all over the world. The present study was carried out to reveal the presence of carbapenem resistant Enterobacteriaceae and bla(KPC,) bla(NDM) and bla(OXA-48) genes responsible for carbapenem resistance in raw milk and to contribute to transmission dynamics and molecular epidemiology of carbapenem resistance, as well as the potential public health risks of milk. In Turkey, there is not sufficient data on the presence and the potential risks posed by carbapenem resistance in animal origin foods. A total of different 427 raw milk samples were collected and subjected to phenotypic microbiological analysis and conventional and Sybergreen real-time PCR targeting bla(KPC,) bla(NDM) and bla(OXA-48) genes. In the phenotypic analyses, suspicious isolates were identified by Vitek-2 compact system and antibiotic resistance profiles were revealed. Two Stenotrophomonas maltophilia inherently resistant to carbapenems were detected in raw milk samples. Acquired carbapenem resistance and related genes were not found in any of the milk samples. The present study revealed that milk is not epidemiologically involved in the transmission of carbapenem resistance. In order to prevent the environmental distribution of antibiotic resistant microorganisms, control of antibiotics used in human and veterinary medicine should be maintained.Öğe Antibiotic Resistance Gene Profiles of Staphylococcus aureus Isolated From Foods of Animal Origin(Kafkas Univ, Veteriner Fakultesi Dergisi, 2018) Hizlisoy, Harun; Ertas Onmaz, Nurhan; Karadal, Fulden; Al, Serhat; Yildirim, Yeliz; Gonulalan, Zafer; Kilic, HuseyinIn this study, the investigation of the antibiotic resistance gene profiles of Staphylococcus aureus isolates from foods of animal origin was aimed. Totally, 95 S. aureus strains, obtained during a period between 2009 and 2012, from culture collection of the Food Hygiene and Technology Laboratory, were examined. The isolates were confirmed by phenotypic tests and PCR. The antibiotic susceptibilities of the isolates were analyzed by disc diffusion method and the minimal inhibition concentrations of the antibiotics were determined by E test. PCR were also utilized for determining the presence of resistance genes including blaZ, ermA, ermC, tetK, tetM, mecA, VanA, VanB, VatA, VatB and aacA-aphD. Resistance to penicillin, tetracycline, vancomycin, erythromycin, cefoxitin, gentamycin and quinupristin-dalfopristin were evident as 81.1%, 28.4%, 18.9%, 17.9%, 9.4%, 9.4% and 3.2% respectively. E test results were compatible with the disc diffusion method. Multidrug resistance was observed from 29.5% of S. aureus isolates. Positive compatibility was observed between conventional methods and PCR for the resistance of the isolates, except for vancomycin. In addition, all of the tested isolates found to include a resistance gene for at least one antibiotic. In conclusion, more efficient interventions must be followed to control the redundant use of antibiotics in veterinary practice. Furthermore, appropriate control measures are needed to be implemented to reduce contamination and the spread of multiresistant S. aureus strains.Öğe Antimicrobial susceptibility and serotype distribution of Listeria monocytogenes isolates obtained from raw milk cheese samples sold in Nigde(ANKARA UNIV PRESS, 2014) Karadal, Fulden; Yildirim, YelizThis study was designed to evaluate public health risks in respect to listeriosis due to consumption of local raw milk cheese sold in villages and public bazaars of Nigde. In addition, this study aims to contribute to the treatment process of listeriosis by determining serotype distribution and antimicrobial susceptibility profiles of the isolates. In the study, two of cheese (1 %) samples of total 200 raw milk cheese samples (100 white cheeses and 100 tulum cheeses) were found contamined with L. monocytogenes. Serotype distribution of the isolates were determined as 1/2a (white cheese isolate) and 4a (tulum cheese isolate). Finally, antimicrobial resistance profiles of the isolates against 11 antibiotics (tetracycline, ciprofloxacin, gentamicin, ampicillin, erythromycin, trimethoprim, vancomycin, chloramphenicol, nalidixic acid, penicillin G and sulphanilamide) were determined and the MIC values were specified by a microdilution method. Both of the isolates were found to be resistant to nalidixic acid but sensitive to the others analysed. As a result, although low L. monocytogenes prevalance rates were detected in this study, it is a public health concern to isolate serotype 1/2a which is secondly incriminated serotype to cause human listeriosis. In addition, it is important in terms of public health to continue surveillance of emerging antimicrobial resistance among L. monocytogenes isolated especially from foods of animal origin though incidence of antibiotic resistance in L. monocytogenes isolates is rare.Öğe Clonal diversity and antifungal susceptibility of Candida spp. recovered from cow milk(Croatian Dairy Union, 2020) Hizlisoy, Harun; Onmaz, Nurhan Ertas; Al, Serhat; Karadal, Fulden; Yildirim, Yeliz; Gonulalan, Zafer; Gumussoy, K. SemihThe aim of this study was the isolation, identification, phylogenetic analysis and antifungal susceptibility of Candida spp. from milk samples of healthy and mastitic cows in Kayseri/Turkey. Milk samples from 300 cows were found to be negative/positive for mastitis with the California Mastitis Test. Candida spp. was isolated by using the Brillance Candida Agar Base. Phenotypic tests, Matrix Assisted Laser Desorption Ionization - Time of Flight (MALDI-TOF), and VITEK-2 analyses were applied to confirm the obtained isolates. Resistance to flucytosine, fluconazole and caspofungin antifungals of the isolates were determined by Etest and VITEK-2. The genetic homologies of Candida spp. isolates were determined by Repetitive Extragenic Palindromic-PCR (RepPCR). In this study 62 (from 53 healthy, 9 mastitic) yeast isolates were obtained and 37 (59.6 %) were identified as non-albicans Candida (NAC) species. Phenotypic tests revealed that out of 62 isolates, 29 (46.7 %), 4 (6.5 %), 3 (4.8 %), 1 (1.6 %) and, 24 (38.7 %) were identified as Candida lusitaniae, Candida catenulate, Candida tropicalis, Candida silvicola and other yeast species, respectively. Only one sample (1.6 %) was identified as Candida albicans by MALDI-TOF however, according to VITEK-2, the agent was not confirmed as C. albicans. According to antifungal susceptibility testing by VITEK-2, one (2.7 %) of the isolates was resistant to fluconazole, one (2.7 %) was resistant to caspofungin, and 4 (10.8 %) were resistant to flucytosine. However, using E test, 10 isolates (27 %) were resistant to flucytosine. Using Rep-PCR, eight genotypic clones were observed. Genotype F (13.8 %) and G (13.8 %; 2 subtypes) were common clones in this study. In conclusion, NAC species were detected in healthy and mastitic cow milk samples. Epidemiological studies need to be conducted to track effectively the main source and to understand the diversity and distribution of the agent. It is necessary to consider the potential risks of yeast contamination in milk for public health. It is essential to focus on adequate sanitation procedures and storage conditions of milk.Öğe Escherichia coli O157 in fish: Prevalence, antimicrobial resistance, biofilm formation capacity, and molecular characterization(Elsevier, 2020) Onmaz, Nurhan Ertas; Yildirim, Yeliz; Karadal, Fulden; Hizlisoy, Harun; Al, Serhat; Gungor, Candan; Disli, H. BurakThis study was performed to survey the incidence of Escherichia coli O157:H7 contamination in fish samples which were obtained from different fish farms and retail markets. For this purpose, a total of 140 fish samples were analyzed according to ISO 16654 and screened for virulence genes by mPCR. Antibiotic susceptibility tests were performed with the disc diffusion method and isolates were genotyped by using Enterobacterial repetitive intergenic consensus (ERIC) PCR. Of the 140 analyzed sample, two (1.4%), from the same farm, were found to be contaminated with E. coli O157 serogroup, one of which harbored stx1 and the other eaeA gene. E. coli O157 serogroup were resistant to only ciprofloxacin and were not capable of forming biofilm and their ERIC-PCR patterns were different. In conclusion, the existence of pathogenic E. coli O157 serogroup in fish samples might be a significant threat to public health and fish could serve as a vehicle for transmission of these bacteria to consumers in Turkey.Öğe Knowledge and attitudes in food safety and the occurrence of indicator bacteria on hands of food handlers at the point of pastrami sale(Ankara Univ Press, 2020) Yildirim, Yeliz; Onmaz, Nurhan Ertas; Gonulalan, Zafer; Hizlisoy, Harun; Al, Serhat; Karadal, Fulden; Kum, ErhanThe aim this study was to evaluate food safety knowledge and attitudes of food handlers and to determine the presence of indicator bacteria on the hands of food handlers in the pastrami retail points in Kayseri, Turkey. Food handlers were interviewed and the samples were taken from their hands by touching the petri dishes. Food handlers' knowledge and attitudes were evaluated by questionnaires and checklists. Conventional methods were followed for microbiological analyses. The presence of total coliforms, E. coli, members of the family Enterobacteriaceae and S. aureus on the hands of food handlers were analyzed. Results indicated that coliforms were present in 37.3% of food handlers hands and 32% exceeded the limit when compared to the literature suggesting a target value of <2.5 cfu/cm(2). E. coli, Enterobacteriaceae and S. aureus were present in 10.6%, 44.6% and 34% of handler's hands, respectively. Food safety knowledge evaluation received high scores with mean score of 69.06%. Only one handler was below the score of 50%. Despite the high scores on food safety knowledge, high numbers of hand samples were found to be contaminated with pathogens. Data obtained from this study reveal that despite their adequate food safety knowledge, food handlers on pastrami retail points were found insufficient for implementation. Therefore, it is not only sufficient to provide food safety trainings but also the sources of problems, such as lack of hygiene infrastructure, in the practice should be identified and resolved in retail points.Öğe Mycotoxigenic and phylogenetic perspective to the yeasts and filamentous moulds in mould-matured Turkish cheese(Elsevier, 2021) Onmaz, Nurhan Ertas; Gungor, Candan; Al, Serhat; Dishan, Adalet; Hizlisoy, Harun; Yildirim, Yeliz; Tekinsen, Filiz KasapThis study was conducted to determine the diversity of yeasts and filamentous moulds in mould-matured cheese (MMC) consumed in Turkey. Overall, 120 samples were collected from 12 different geographical locations between March 2016 and April 2017. The morphological observation was applied in combination with matrixassisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) and molecular analyses to determine yeasts and filamentous moulds in the cheeses. High-performance liquid chromatography (HPLC) technique was used to evaluate the ability of mycotoxins production of fungal isolates and the presence of mycotoxins in cheese samples. A total of 241 fungi (81 filamentous moulds and 160 yeast) were recovered, and Penicillium roqueforti and Debaryomyces hansenii were the most frequently isolated species in all cheese samples. The rep-PCR results indicated a high level of genetic diversity among fungal isolates, regardless of isolation source or geographical origin. Filamentous mould strains isolated from MMC were found to synthesize at least one mycotoxin (Aflatoxin B1, B2, G1 and G2, citrinine, cyclopiazonic acid, mycophenolic acid, ochratoxin A, penicillic acid and roquefortine C). Although mycotoxin producing ability was observed from all isolates, none of the cheese samples were found positive for these mycotoxins. AFM1 was detected in 8 (6.6%) MMC samples from which 2 (1.6%) were above the legal limits (0.05 mu g/kg) set by the Turkish Food Codex (TFC) and European Commission (EC). In conclusion, Turkish MMCs were found to be contaminated with toxigenic fungi, so a potential public health risk, while low, exists. Therefore, the selection of nontoxigenic filamentous mould strains for cheese manufacturing and control of the ripening conditions is a critical need to ensure the quality and safety of Turkish MMC.Öğe The determination of meat species by PCR-RFLP method using mitochondrial ND4 gene in pastirma, a traditional dry cured meat product(Tubitak Scientific & Technological Research Council Turkey, 2020) Al, Serhat; Hizlisoy, Harun; Ertas Onmaz, Nurhan; Karadal, Fulden; Gungor, Candan; Yildirim, Yeliz; Gonulalan, ZaferPastirma is a high value, traditional, dry cured, and edible coated meat product. For economic and sociocultural reasons, it is important to know which meat species are used in pastirma. The present study aims to carry out the determination of the meat species in pastirma. A total of 144 pastirma samples were collected from different stores. After genomic DNA isolation, the total DNAs obtained were subjected to polymerase chain reaction (PCR) using specially designed novel primers amplifying the mitochondrial ND4 (MT-ND4) gene region, specific for cattle (Bos taurus), water buffalo (Bubalus bubalis), horse (Equus caballus), and donkey (Equus asinus) species. For the identification of the meat species, gel purified 952 bp PCR products were digested with fast digest SaqAI restriction enzymes selected based on preliminary in silico analyses. The results of the present study revealed that all of the pastirma samples were made from cattle meat. Cross-reactions and false-positive identifications are serious problems in routine determination of the meat species in food control laboratories. It is important to perform fast, inexpensive determination with high sensitivity and specificity for the identification of meat species. This study has shown that meat species can be detected with high specificity in products such as pastirma, which uses large pieces of meat cuts.Öğe Toxigenic Staphylococcus aureus in some animal- originated food products marketed in Turkey: presence and Public Health concerns(Ist Zooprofilattico Sperimentale Abruzzo & Molise G Caporale-Izs A&M, 2024) Karadal, Fulden; Onmaz, Nurhan Ertas; Hizlisoy, Harun; Yildirim, Yeliz; Al, Serhat; Gonulalan, Zafer; Bagci, CemalettinThis study aimed to detect the presence of Staphylococcus aureus in some animal source food (ASF) including emulsified meat products (sausage and salami), dry fermented meat product (soudjouk), semi dry meat product (pastrami) and raw chicken meat. Sixty six (38.8%) of 170 samples were found to be positive for S. aureus. . It was determined that S. aureus was found in 17 (56.6%) salami, 27 (54%) raw chicken meat, 9 (30%) soudjouk, 9 (30%) pastrami, 4 (13.3%) sausage samples. Staphylococcal enterotoxins (SEs) were identified in 5 out of 66 (7.5 %) isolates food matrices including 3 (4.5%) SEA, 2 (3.03%) SEC. The sea and sec genes were detected in 3 (4.5%) of 66 isolates. The results of this study highlight the need to provide suitable control strategies concerning production, sales, and storage to prevent the spread of enterotoxigenic S. aureus isolates in ASF. The key contribution of this study is its revelation of the presence of S. aureus in animal products sold in Turkish local markets, highlighting the potential public health risks associated with animal foods.
