Yeliz Yildirim

The objectives of the study were to determine the prevalence of carbapenem-resistant Gram-negative bacteria and assess the potential risks associated with cattle slaughterhouse wastewater. A total of 270 wastewater samples were collected from 10 different cattle slaughterhouses for microbiological analysis. Conventional culture methods were employed, followed by disc diffusion, the Modified Carbapenem Inactivation Method (mCIM), and the Modified Hodge Test (MHT) to identify carbapenem resistance. The Vitek® 2 compact system was used for species identification and antibiotic susceptibility profiling. Conventional and quantitative PCR (qPCR) were performed to detect specific carbapenemase genes (blaKPC, blaNDM, and blaOXA-48), among the collected 17 (6.30%) carbapenem-resistant isolates, one Pseudomonas fluorescens (0.37%), one Aeromonas hydrophila (0.37%), and two Aeromonas sobria (0.74%) exhibited resistance to meropenem. Additionally, six P. fluorescens (2.22%) and two A. hydrophila (0.74%) isolates demonstrated intermediate resistance to meropenem. Furthermore, five carbapenem-resistant isolates were identified as Stenotrophomonas maltophilia (1.85%), known to be inherently resistant to most antibiotics. Ten different antibiotics were evaluated in the antibiotic resistance panel and all Aeromonas isolates were found to be resistant to cefazolin and one A. hydrophila was detected as multi-drug resistant. The revealed data indicates that slaughterhouse wastewater can serve as a reservoir for antibiotic-resistant opportunistic pathogens. However, it may not pose a substantial risk for the distribution of carbapenemases, thereby mitigating concerns related to potential public health and environmental hazards associated with this aspect of slaughterhouse operations. This study contributes to understanding of antibiotic resistance in livestock-related environments and underscores the importance of continued monitoring and surveillance.

Summary: The study aimed to determine the prevalence and characteristics of Salmonella isolated from raw chicken meat and products. For this purpose, a total of 293 samples were collected, including chicken breast (n = 90), skinned drumstick (n = 80), skinned chicken chop (n = 42), wing (n = 32), chicken offal (n = 27) and chicken patty (n = 22). The samples were subjected to Salmonella enterica. detection and the obtained suspicious isolates were confirmed by conventional PCR. Their phenotypical antibiotic resistance profiles were subsequently determined. The prevalence of Salmonella Enteritidis and Typhimurium serovars among S. enterica isolates were investigated using TaqMan probe Real‐Time PCR (qPCR) analysis, and the detected serovars were evaluated with whole genome sequencing. In the study, 112 (38.22%) of the 293 chicken samples contained S. enterica, with five (4.46%) and one (0.89%) of the isolates identified as Salmonella Enteritidis and Typhimurium, respectively. Antibiotic resistance analysis revealed that all isolates were sensitive to Meropenem and Aztreonam, while the most resistant antibiotics were Doxycycline (96.42%) and Trimethoprim‐sulfamethoxazole (71.42%). Whole genome sequencing, specifically SNP‐based phylogenetic analyses, indicated that Salmonella Enteritidis and Typhimurium isolates were distinct clones. All Salmonella Enteritidis isolates shared the same antigenic profiles (9: g, m:‐) and cgMLST types of 11, while the Salmonella Typhimurium isolate had cgMLST type 19 and a 4:i:1,2 antigenic profile. It was observed that the phenotypic resistance profiles of the isolates were consistent with the whole genome characterisation. The data obtained in the study reveal the continued importance of Salmonella monitoring for the poultry industry across different regions of Türkiye to maintain food safety. Chicken meat and products are indispensable to public health in providing healthy nutrition and access to animal protein. The microbiological and epidemiological risks observed in mass production can be minimised, particularly by integrating epidemiological and molecular findings with an effective strategy.

In this study, it was aimed to qualitatively determine Bisphenol A and dibutyl phthalate residues in carboy, pet bottled and tap waters used as drinking water in Kayseri-Türkiye. Being used as an additive in the production of many products and plastics frequently used in daily life, BPA and phthalates are associated with a variety of health issues and environmental problems. Within the scope of this study, a total of 20 drinking water samples (9 pet, 7 carboy and 4 tap water) were analyzed in terms of dibutyl phthalat (DBP), BPA and BPA derivatives (Bisphenol S and Bisphenol F). Among the pet bottled water samples; 8 (88.88%) were found to be contaminated with BPA, 5 (55.55%) with DBP and 7 (77.77%) with BPA derivatives, while 1(14.28%) of the carboy water samples were found contaminated with BPA and 7(100%) with DBP. Among the tap water samples, 2 (50%) were contaminated with BPA and 4 (100%) with DBP. No BPA derivatives were found in carboy and tap water samples while pet bottled waters were found posi- tive for all three contaminants. On the other hand, all carboy and tap waters were found contaminated with phthalates. The findings of this study reveal that the most variety of contamination for these chemicals is determined in pet bottled waters. This study highlighted the situation of BPA and phthalate residues in drinking water sources. Measures should be taken to prevent the contamination of all types of drinking water and to systematically examine the BPA and phthalate-related safety of drinking waters. Further investigation is needed to determine and quantify the occurrence of the target compounds.

1. The Shiga toxin-producing Escherichia coli (STEC) is a hazardous zoonotic agent for chicken meat consumers. This study determined the serogroups and evaluated the virulence genes, antibiotic resistance, biofilm-forming profiles and genetic relationships of STEC isolates in chicken meat. 2. A total of 100 samples belonging to dressed-whole chicken and different parts of the chicken (wing, breast, thigh, drumstick) were collected between September and November 2019 from different retail markets in Kayseri, Türkiye. 3. Phenotypic (identification, disc diffusion test, Congo red agar and microtitre plate tests) and molecular tests (identification, serogrouping, virulence factors, biofilm, antibiotic susceptibility, 16S rRNA sequencing and enterobacterial repetitive intergenic consensus-PCR for typing of the isolates) were carried out. 4. E. coli was isolated from 35% of the samples and 35% of the samples harboured at least one STEC. Among 35 STEC isolates, 3 (8.5%), 6 (17.1%), 2 (5.7%) and 3 (8.5%) were found to be positive for fliCH2, fliCH8, fliCH11, fliCH19 genes, respectively. Out of 35 STEC positive isolates, 4 (11.4%) were identified as E. coli O157, from which 2 (5.7%) were E. coli O157:H7. E. coli O157 was detected in two (10%), one (5%), one (5%) of the thigh, drumstick and whole chicken samples, respectively. 5. Biofilm-forming ability was reported in 33 (94.2%) of 35 E. coli isolates, whilst the biofilm-associated genes detected among 35 STEC isolates included csgA (88.5%), fimH (88.5%), bcsA (85.7%), agn43 (14.2%) and papC (8.5%). The STEC strains showed resistance against ampicillin (88.5%) and erythromycin (88.5%), followed by tetracycline (74.2%) and gentamicin (25.7%). However, the distribution of isolates harbouring bla_CMY, ere(A), tet(A) and aac(3)-IV antibiotic resistance genes was found to be 17.1%, 11.4%, 85.7% and 5.7%, respectively. 6. ERIC-PCR showed that E. coli strains obtained from different parts and whole of chicken samples had genetic diversities. ERIC-PCR patterns grouped strains of 35 STEC into eight clusters designated A-H, with 73% similarity. Proper hygiene measures and staff training are essential for public health during poultry processing and in retail stores to control STEC.

Tr en Bu çalışmada, Kayseri ve Niğde’de perakende olarak satışa sunulan bazı tüketime hazır gıdalarda Listeria monocytogenes varlığının araştırılması, tespit edilen izolatların moleküler karakterizasyonu ve antibiyotik dirençlilik profillerinin belirlenmesi amaçlanmıştır. Bu amaçla farklı dönemlerde olmak üzere farklı satış noktalarından 64 etsiz çiğ köfte, 54 mayonez bazlı Rus salatası ve 25 peynir tatlısı örneği toplanmıştır. Tüketime hazır gıda numunelerinden konvansiyonel yöntemlerle Listeria monocytogenes izolasyonu gerçekleştirilmiştir. Elde edilen Listeria spp. şüpheli izolatlar Microbact Listeria 12L Kit ile tür bazında identifiye edilmiştir. Fenotipik olarak L. monocytogenes olduğu belirlenen izolatlar Polimeraz Zincir Reaksiyonu (PZR) ile doğrulanmıştır. Listeria monocytogenes izolatlarının klonal yakınlıkları Enterobacterial Repetitive Intergenic Consensus (ERIC) PZR ile belirlenmiş, ayrıca Multipleks PZR (mPZR) yöntemi ile nesil ve serotip analizleri gerçekleştirilmiştir. İzolatların antibiyotik duyarlılık profillerinin belirlenmesinde disk difüzyon metodu kullanılmıştır. Çalışma kapsamında etsiz çiğ köfte numunelerinin sekizinden (%12.5) ve Rus salatası örneklerinin ise birinden (%1.85) L. monocytogenes izole edilmiştir. Araştırılan peynir tatlısı örneklerinin hiçbirinde L. monocytogenes tespit edilmemiştir. Yapılan ERIC PZR analizi sonucunda izolatların dört farklı tipte bant profili ortaya koydukları belirlenmiştir. L. monocytogenes izolatlarının nesillerinin belirlenmesi amacıyla yapılan Allelspesifik Oligonükleotid (ASO) PZR analizinde tüm izolatların birinci nesile ait oldukları; mPZR ile yapılan serotiplendirmede ise tüm izolatların 4b serotipi olduğu ortaya konulmuştur. Çalışma kapsamında elde edilen sekiz izolatın birinin ampisiline; birinin meropeneme, üçünün eritromisine ve ikisinin ise trimetoprim/sülfometaksazol’e dirençli oldukları belirlenmiştir. Bu çalışma ile halk sağlığı açısından ciddi riskler oluşturan ve etkin kullanılan antibiyotiklere karşı direnç gösterebilen L. monocytogenes’in tüketime hazır gıdalar aracılığıyla dağılım gösterebileceği belirlenmiştir. Toplum tarafından talep gören tüketime hazır gıdaların üretiminde, gıda güvenliği yönetim sistemlerinin etkin şekilde kullanılması ve üretim sonrasında olası kontaminasyonların önüne geçilmesi amacıyla gıda muhafaza ilkelerinin göz önünde bulundurulması gerekmektedir. In this study, it was aimed to investigate the presence of Listeria monocytogenes in ready-to-eat foods retailed in Kayseri and Nigde province of Turkey and to determine the molecular characterization and antibiotic resistance profiles of the detected isolates. For this purpose, 64 cigköfte without meat, 54 mayonnaise based Russian salads and 25 cheese desserts samples were collected from different sales points. Listeria monocytogenes isolation was carried out by conventional method in ready-to-eat food samples. Obtained Listeria spp. isolates were identified by species with the Microbact Listeria 12L Kit. Isolates phenotypically determined as L. monocytogenes were confirmed by Polymerase Chain Reaction (PCR). Clonal relationship of L. monocytogenes isolates were revealed by Enterobacterial Repetitive Intergenic Consensus (ERIC) PCR, and lineage and serotype analyzes were performed by Multiplex PCR (mPCR) methods. Disc diffusion method was used to determine the antibiotic susceptibility profiles of the isolates. In the study, L. monocytogenes was isolated in eight of çiğköfte samples (12.5%) and one of Russian salad samples (1.85%). None of the cheese dessert samples were contaminated with L. monocytogenes. As a result of the ERIC PCR analysis, it was determined that the isolates separated four different type of band profiles. In the Allelespecific oligonucleotide (ASO) PCR analysis performed to determine the lineage of L. monocytogenes isolates, it was revealed that all isolates belong to the Lineage I, and serotyping with mPCR, all isolates were determined as serotype 4b. One of the eight isolates obtained in the study was resistant to ampicillin; one was resistant to meropenem, three to erythromycin and two to trimethoprim/ sulfamethoxazole. Within the study, it was determined that antibiotic resistant L. monocytogenes, can be distributed with ready-to-eat foods and poses serious risks in terms of public health. It is considered that food preservation principles should be taken into consideration and using food safety management systems effectively in the production process of ready-to-eat foods that are highly demanded by the society to prevent possible contaminations after production.

Essential oils (EO) could address the need for alternative additives for food producers to maintain safety and quality of meat products. The aim of this study was to evaluate antimicrobial activity of Thymbra spicata L. subsb. spicata EO on Escherichia coli and Salmonella Typhimurium in Turkish dry fermented sausage (sucuk). Antimicrobial activity of EO, obtained from the collected plant, has been demonstrated in vitro and in sucuk matrices against selected foodborne pathogens. In the composition of the essential oil obtained in the study, total of 47 components (99.41%) were assayed including mainly carvacrol (43.6%), ɣ-terpinene (16.69%) and p-cymen (13.97%). Thymbra spicata L. observed to have antimicrobial effect on the related pathogens in vitro however, increased amount of EO use, to be antimicrobiologically effective in sucuk, negatively affected the organoleptic properties. It is concluded that natural additives could potentially be used as an alternative to chemicals in food technology to prevent foodborne diseases and to extend the shelf life of products. Further studies are needed to evaluate the combined and synergetic effects of different EOs and other preservation methods to cope with foodborne pathogens in the food matrices.

2000’li yıllardan önce gıdalardaki biyolojik tehlikeler endişe yaratırken kimyasal endüstrisindeki atılımlar gıdalardaki kimyasal tehlikeleri ön plana taşımıştır. İkinci dünya savaşından sonra kimyasal kullanımı kırılmaz biberondan, ev eşyasına ve yemek servisine kadar hayatın her alanında yaygınlaşmıştır. Günlük hayatımızda kullandığımız eşyaların yapısında 80 binden fazla kimyasal bulunmaktadır. Bu kimyasalların çoğu halk sağlığı açısından henüz test edilmiş değildir. Kimyasallara; “aksi kanıtlanmadığı sürece masumdur” yaklaşımı uygulanmaktadır ki bu yaklaşım halk sağlığı açısından risk teşkil etmektedir. Günümüzde normal bir insanın kanında ve idrarında 200’den fazla kimyasal bulunmaktadır. Bu kimyasallar amniyotik sıvıdan, anne sütünden, bebek kordonundan ve mekonyumdan da analiz edilebilmektedir. Erken dönemde maruz kalınan kimyasallar ileri yaşlardaki kronik hastalıkların temelini oluşturmaktadır. Bu toksikantlardan en çok fitalatlar ve bisfenol-A (BPA) üzerinde durulmaktadır. Fitalatlar, plastikleri yumuşatmak, bisfenol-A ise sertleştirmek için kullanılmakta, fitalatlar aynı zamanda kozmetiklerde de kullanılmaktadır. Bu kimyasallar vücutta hormonları taklit ederek endokrin sistemi ve fizyolojik fonksiyonları bozmaktadır. Gebelik esnasında maruz kalındığında bu kimyasallar; hamileliğin hangi döneminde maruz kalındığına bağlı olarak hem anneyi hem de fötal gelişimi etkilemekte, başta erkek çocuklar olmak üzere beyin ve üreme organlarının gelişimini engellemektedir. Bu kimyasalların etkileri, ne miktarda, ne kadar süre alındıklarına ve bireylerin yaşam tarzlarına göre değişmektedir. Bu kimyasallar beyinde üretilen hormonları da etkileyerek çocuklarda disleksi ve hafıza problemlerine neden olabilmektedir. Erken yaşlarda maruziyet ileriki yaşlarda davranış bozuklukları, depresyon, anksiyete, allerji, solunum yolu hastalıklarına sebebiyet vermekte, pubertal gelişimi, obezite, diyabet ve tümörogenesisi tetiklemektedir. Özellikle anne karnında, düşük dozdaki kimyasallar bile bebek beyninde büyük hasarlara neden olabilmekte, ileride hızlı düşünmeyi ve tepki vermeyi engelleyebilmektedir.

The 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/cm2. 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.