Yazar "Soykut, Esra Acar" seçeneğine göre listele
Listeleniyor 1 - 12 / 12
Sayfa Başına Sonuç
Sıralama seçenekleri
Öğe Applications of bacteriophage cocktails to reduce salmonella contamination in poultry farms(Springer, 2022) Evran, Şefika; Tayyarcan, Emine Kübra; Soykut, Esra Acar; Boyacı, İsmail HakkıSalmonella contamination is a critical problem in poultry farms, with serious consequences for both animals and food products. The aim of this study is to investigate the use of phage cocktails to reduce Salmonella contamination in poultry farms. Within the scope of the study, Salmonella phages were isolated from chicken stool. After the host range of phages was determined, morphological characterization was performed through transmission electron microscopy analysis. Then, replication parameters and adsorption rates were determined by one-step growth curves. After that, phage cocktail was prepared, and its effectiveness was tested in three environments, which were drinking water, shavings, and plastic surfaces. The results obtained have demonstrated that the phage cocktail can reduce Salmonella count up to 2.80 log(10) units in drinking water, up to 2.30 log(10) units on shavings, and 2.31 log(10) units on plastic surfaces. It has been determined that phage cocktails could be a successful alternative in reducing Salmonella contamination in poultry environment. This work is the first study to investigate the use of phage cocktails for reducing Salmonella contamination in poultry water and on shavings, and it is presumed that the results obtained will contribute to the fight against pathogens by making them applicable to poultry farms.Öğe Determination of yolk: White ratio of egg using SDS-PAGE(Korean Society Food Science & Technology-Kosfost, 2020) Uysal, Reyhan Selin; Soykut, Esra Acar; Boyacı, İsmail HakkıThe aim of present study was to determine liquid egg adulteration based on yolk:white ratio of egg using sodium dodecyl sulphate-polyacrylamide gel electrophoresis and by measuring Brix. To construct a calibration model, liquid egg samples were prepared by mixing egg yolk and white (yolk:white) at different concentrations. A high coefficient of determination value (R-2 = 0.992) was obtained. Limit of detection and limit of quantification were estimated as 62 g/kg and 187 g/kg. The accuracy of the model was tested using eleven LWE samples, and the yolk ratios of 90.9% of these samples were predicted successfully. Liquid whole egg (LWE) containing additional egg white up to 30% was also predicted with a low relative error of less than 10%. Yolk:white ratio of LWE samples and authentication of the components of LWE (containing extra white or water) can be determined using proposed method.Öğe Evaluating the efficacy of a phage cocktail against Pseudomonas fluorescens group strains in raw milk: microbiological, physical, and chemical analyses(Springer, 2024) Tayyarcan, Emine Kubra; Evran, Eylul; Guven, Kubra; Ekiz, Esra; Soykut, Esra Acar; Boyaci, Ismail HakkiThe objective of this study was to investigate the effectiveness of a phage cocktail against Pseudomonas fluorescens group and its effect on the microbial, physical and chemical properties of raw milk during different storage conditions. A phage cocktail consisting of Pseudomonas fluorescens, Pseudomonas tolaasii, and Pseudomonas libanensis phages was prepared. As a result, reductions in fluorescent Pseudomonas counts of up to 3.44 log units for the storage at 4 degrees C and 2.38 log units for the storage at 25 degrees C were achieved. Following the phage application, it is found that there was no significant difference in the total mesophilic aerobic bacteria and Enterobacteriaceae counts. However, it was observed that the number of lactic acid bacteria was higher in phage-treated groups. The results also showed that pH values in the phage added groups were lower than the others and the highest titratable acidity was obtained only in the bacteria-inoculated group. As a future perspective, this study suggests that, while keeping the number of target microorganisms under control in the milk with the use of phages during storage, the microbiota and accordingly the quality parameters of the milk can be affected. This work contributes to the development of effective strategies for maintaining the quality and extending the shelf life of milk and dairy products.Öğe GELENEKSEL YOĞURTLARDAN İZOLE EDİLEN LAKTİK ASİT BAKTERİLERİNİN MALDI TOF MS BİOTYPER SİSTEMİ İLE TANIMLANMASI VE BAZI STARTER KÜLTÜR ÖZELLİKLERİNİN BELİRLENMESİ(2022) Encu, Şeyma Betül; Soykut, Esra Acar; Çakir, IbrahimBu çalışmada Batı Karadeniz Bölgesi’nde, beş ilden toplanan, geleneksel yöntemlerle üretilmiş yoğurtlardan laktik asit bakterilerinin izolasyonu, tanımlanması, bazı starter kültür özelliklerinin belirlenmesi amaçlanmıştır. Suşların tanımlanması MALDI-TOF MS Biotyper sistemi ile gerçekleştirilmiştir. İzole edilen 84 izolattan 2’si Lactobacillus helveticus, 2’si Lactiplantibacillus plantarum, 3’ü Limosilactobacillus fermentum, 1’i Enterococcus faecalis ve 76’sı Lactobacillus delbrueckii olarak tanımlanmıştır. İzolatların eritromisin, teikoplanin, streptomisin, rifampisin, amfisilin, klindamisin, sefotaksim, kloramfenikol, tetrasiklin ve vankomisine karşı duyarlı, nalidiksik asit, siprofloksasin, ofloksasin, gentamisin ve trimethoprim sülfametoksazole karşı dirençli oldukları tespit edilmiştir. İzolatların Salmonella Typhimurium ve E. coli O157:H7’ye karşı antimikrobiyal etki gösterdiği ancak Bacillus cereus, Listeria monocytogenes ve Staphylococcus aureus’a karşı antimikrobiyal etkisinin düşük olduğu tespit edilmiştir. İzolatlardan 8’inin ürettiği asitliğin %0.9 ve 0.95 arasında olduğu bulunmuştur. Ayrıca 74 izolatın diasetil üretimi gerçekleştirdiği belirlenmiştir. Starter olma potansiyeli yüksek 26 suşun proteinaz aktivitesi ve fajlara karşı direnç durumu incelenmiştir. Suşlardan 5’inin proteolitik aktivite göstermediği ve faj direnci testi sonuçlarına göre izolatlardan 8 tanesi ?709-X1 fajına karşı duyarlı olup, 12 adet Lactobacillus delbrueckii izolatının ise çalışmada kullanılan 15 farklı bakteriyofaja karşı dirençli oldukları belirlenmiştir. Çalışma sonuçlarına göre izole edilen kültürlerin incelenen özellikler açısından starter kültür olarak kullanılabilme potansiyeline sahip oldukları belirlenmiştir.Öğe Gıda Kaynaklı Patojen Bakterilere Etkili Bakteriyofajların Sınıflandırılması ve Karakterizasyonu(2021) Soykut, Esra Acar; Boyaci, Ismail HakkiGıda kaynaklı hastalıklar, gelişen tanı-tedavi yöntemleri ve alınan önlemlere rağmen günümüzde hala en önemli sağlık sorunlarının başında gelmektedir. Salmonella Enteritidis, Salmonella Typhimurium ve Escherichia coli O157:H7 hem hammaddede hem de işlenmiş gıda ürünlerinde sorun yaratan patojenlerdendir. Gıda kaynaklı bu patojenler pek çok ciddi rahatsızlığa sebep olmaktadır. Bazı suşlarının antibiyotik direnci de göstermesi bu bakterilerin eliminasyonu için alternatif yolların aranmasını gerekli kılmıştır. Bakterileri spesifik olarak enfekte eden bakteriyofajların kullanıldığı faj terapi, son yıllarda oldukça öne çıkan bir alternatif yöntem halini almıştır. Fajlar, konakçı bakterileri ile karşılaştıklarında onların metabolizmasını ele geçirerek kendi kopyalarını oluşturmakta ve aynı zamanda bakterinin ölümüne yol açmaktadır. Bu nedenle bakteri eliminasyonu için çok güçlü doğal ajanlar olarak görülmektedirler. Salmonella ve E. coli?ye etkili fajlar, insan sağlığı ve gıda güvenliği dikkate alındığında farklı amaçlar için kullanılabilmektedir. Bu amaçlardan biri, fajların söz konusu patojenlerin neden olduğu hastalıkların tedavisinde antibiyotik yerine kullanılmasıdır. Diğer amaçlar ise gıda güvenliğini sağlamak için ilgili gıdanın yüzeyinin fajlar ile muamele edilmesi ya da kimyasal dezenfektanlar yerine yüzey dezenfeksiyonunda fajların kullanılması şeklindedir. Uygulama alanları gittikçe yaygınlaşan faj terapinin, daha etkin, daha kapsamlı ve verimli bir şekilde hayata geçirilebilmesi için kullanılacak fajların özelliklerinin iyi bir şekilde ortaya konması, sınıflandırma ve karakterizasyonunun yapılması büyük önem taşımaktadır. Bu proje kapsamında, doğal kaynaklardan izole edilmiş olan S. Enteritidis, S. Typhimurium ve E. coli O157:H7 fajlarının konakçı özgüllükleri ile RFLP analizleri göz önünde bulundurularak sınıflandırılmaları, toksik gen bölgesi içerip içermediğinin kontrol edilmesi ve replikasyon parametrelerinin belirlenerek karakterize edilmeleri amaçlanmıştır. Bu amaçla, zenginleştirme, stok yenileme ve titre belirleme aşamasından geçerek titresi DNA izolasyonuna uygun seviyeye getirilecek fajların konakçı spektrumları belirlenmiş ve TEM görüntüleri alınmıştır. Daha sonra bu fajların DNA?ları izole edilmiş ve sınıflandırma çalışmalarında temel oluşturan RFLP analizleri yapılmıştır. Enzim kesimleri sonucunda oluşan fragmentler ile fajların birbirinden farklılıkları ortaya konmuştur. Bunu takiben fajların genotoksisiteleri kontrol edilmiştir. Ayrıca fajların gelişme eğrileri çıkarılarak latent dönem süresi ile patlama büyüklükleri hesaplanmış, daha sonra adsorpsiyon hızları belirlenmiş, böylece replikasyon parametreleri ortaya konmuştur. Son olarak, konakçı spektrumu ve RFLP sonuçlarına göre faj miksleri hazırlanarak bakteri eliminasyon etkinliği saptanmış ve hem insan/hayvan denemelerinde kullanılacak, hem de gıda güvenliği için prosesin herhangi bir aşamasında uygulanacak gıda ürünlerinde kullanıma uygun, özellikleri belirli bir faj koleksiyonu oluşturulmuştur. Böylece ülkemizde faj terapi konusunda bilimsel ve pratik uygulama açısından göze çarpan eksikliğin giderilmesi için bir adım atılmıştır.Öğe Investigation of different interactions between Staphylococcus aureus phages and pomegranate peel, grape seed, and black cumin extracts(Wiley, 2019) Tayyarcan, Emine Kübra; Soykut, Esra Acar; Yılmaz, Özay Menteş; Boyacı, İsmail Hakkı; Khaaladi, Maha; Fattouch, SarniToday, antibiotic resistance is one of the most crucial problems so that researchers have begun to search for alternatives to antibiotics. Among these alternatives, phage therapy and phytotherapy became prominent. The present study aims to put forward a different approach by combining these two methods. For this purpose, Staphylococcus aureus phages were isolated from commercial mixtures. After that, extraction of phenolic compounds from pomegranate peels (Ps), grape seeds (GSs), and black cumin (NS) was carried out and antimicrobial activities were determined. Phage-phenolic interactions were investigated by examining the effect of phenolic extracts on phage plaque sizes and then on phage titer and bacteria count. As a result, it was found that only the NS extract had a positive effect on phage activity and increased the size of phage plaques. However, no synergistic effect was observed in experiments performed in liquid media. It was also found that P and GS extracts inhibited phage activity. Practical Applications The present study was focused on effects of extracts obtained from pomegranate peel, grape seed, and black cumin on Staphylococcus aureus phage activity. It is known that antibiotic resistance constitutes a major obstacle to the pathogen elimination. In this study, phage therapy and phytotherapy, which are prominent methods in pathogen elimination, have been combined and the effect of phenolic compounds isolated from natural sources on phage activity and bacteria count have been examined. Given the results of the current study, it has been demonstrated that the combined use of phages and antimicrobial compounds could be an important alternative to combating pathogens. It is thought that this combined method should be taken into consideration both in the practice of phage therapy on humans and animals, and in applications in the food industry.Öğe Investigation of phage and molasses interactions for the biocontrol of E. coli O157:H7(Canadian Science Publishing, 2022) Evran, Şefika; Tayyarcan, Emine Kübra; Soykut, Esra Acar; Güven, Burcu; Velioğlu, Serap Duraklı; Boyacı, İsmail HakkıResistance to antibiotics is one of the most critical health problems in the world. Therefore, finding new treatment methods to be used as alternatives to antibiotics has become a priority for researchers. Similar to phages, certain products containing antimicrobial components, such as molasses, are widely used to elimi-nate resistant bacteria. Molasses has a strong antimicrobial effect on bacterial cells, and this effect is thought to be due to the breakdown of the cytoplasmic cell membrane and cell proteins of the polyphenols in molas-ses. In the present study, phage-molasses interactions were investigated to examine the effects of concomi-tant use. It was found that molasses samples increased the size of phage plaques by up to 3-fold, and MIC and 1/2 x MIC concentrations of molasses increased the burst size of phages. Although no synergistic effect was found between the phage and molasses, the antimicrobial activities of the components and the effect of mo-lasses on phage activity were demonstrated.Öğe Isolation and characterization of yogurt starter cultures from traditional yogurts and growth kinetics of selected cultures under lab-scale fermentation(Taylor & Francis Inc, 2023) Çakmakoğlu, Selma Kayacan; Vurmaz, Melike; Bezirci, Emine; Kaya, Yasemin; Dikmen, Hilal; Encu, Betül; Soykut, Esra Acar; Çakır, İbrahimThe development of new starter cultures is a crucial task for the food industry to meet technological requirements and traditional products are important reservoirs for new starter cultures. In this respect, this study aimed to isolate, identify, and determine the technological characteristics of Lactobacillus delbrueckii subsp. bulgaricus and Streptococcus thermophilus strains originated from traditional yogurt samples. Genotypic discrimination of 200 isolates revealed the presence of distinct 19 S. thermophilus and 11 Lb. delbrueckii subsp. bulgaricus strains as potential starter cultures. Strain-specific properties determined the acidification capacity of the yogurt starter cultures and a higher acidification capacity was observed for S. thermophilus strains compared to Lb. delbrueckii subsp. bulgaricus strains. Proteolytic activity was found between 0.012-0.172 and 0.078-0.406 for S. thermophilus and Lb. delbrueckii subsp. bulgaricus strains, respectively. 4 of S. thermophilus and 3 of Lb. delbrueckii subsp. bulgaricus strains were found resistant to all tested bacteriophages. The antibiotic susceptibility tests of the isolates revealed that a very low antibiotic resistance was observed for the yogurt starter cultures. Finally, the growth kinetics of selected strains were determined and the maximum specific growth rate of selected S. thermophilus and Lb. delbrueckii subsp. bulgaricus was calculated as 0.527 h(-1) and 0.589 h(-1), respectively.Öğe Microencapsulation of phages to analyze their demeanor in physiological conditions(Springer, 2019) Soykut, Esra Acar; Tayyarcan, Emine Kübra; Evran, Şefika; Boyacı, İsmail Hakkı; Çakır, İbrahimNowadays, phage therapy emerges as one of the alternative solutions to the problems arising from antibiotic resistance in pathogenic bacteria. Although phage therapy has been successfully applied both in vitro and in vivo, one of the biggest concerns in this regard is the stability of phages in body environment. Within the scope of this study, microencapsulation technology was used to increase the resistance of phages to physiological conditions, and the resulting microcapsules were tested in environments simulating body conditions. For this purpose, Bacillus subtilis, Salmonella enterica subsp. enterica serovar Enteritidis (Salmonella Enteritidis), and Salmonella enterica subsp. enterica serovar Typhimurium (Salmonella Typhimurium) phages were isolated from different sources and then microencapsulated with 1.33%(w/v) sodiumalginate using a spray dryer to minimize the damage of physiological environment. Stability of microcapsules in simulated gastric fluid and bile salt presence was tested. As a consequence, the maximum titer decrease of microencapsulated phages after 2-h incubation was found to be 2.29 log unit for B. subtilis phages, 1.71 log unit for S. Enteritidis phages, and 0.60 log unit for S. Typhimurium phages, while free phages lost their viability even after a 15-min incubation. Similarly, microencapsulation was found to increase the stability of phages in the bile salt medium and it was seen that after 3 h of incubation, the difference between the titers of microencapsulated phages and free phages could reach up to 3 log unit.Öğe SERS-based rapid assay for sensitive detection of Group A Streptococcus by evaluation of the swab sampling technique(Royal Soc Chemistry, 2019) Eryılmaz, Merve; Soykut, Esra Acar; Çetin, Demet; Boyacı, İsmail Hakkı; Suludere, Zekiye; Tamer, UğurBeta-hemolytic, Group A Streptococcus pyogenes (GAS) is a life-threating pathogen and the reason for prominent disease, pharyngitis. The conventional analysis of GAS, gold standard, takes 48 hours and the related rapid tests lack in accuracy and sensitivity. In this study, firstly, the efficiency of swab sampling, which is a must in the GAS detection, was discussed with the proposed surface-enhanced Raman spectroscopy (SERS)-based batch assay and each step was controlled by the plate-counting method. Secondly, SERS-based lateral flow immunoassay (LFIA) test strips were constructed and the variation in the SERS intensity of 5,5'-dithiobis (2-nitrobenzoic acid) (DTNB) was observed. Thus, a linear correlation was found with a R-2 value of 0.9926 and the LOD was calculated to be 0.2 CFU mL(-1) of GAS which could be counted as one cell. The combination of the gold standard with the LFIA-SERS technique enabled the fast and accurate pathogen detection. In addition, GAS was quantified with paper-based test strips up to 100 CFU ml(-1) level of bacteria for the first time without any interference. Besides, this study was featured with the discussion of the whole cell and pretreated cell detection of pathogens with LFIAs. Therefore, this work enlightens the points that have never been discussed on pathogen detection with paper-based platforms.Öğe TAZE DİLİMLENMİŞ MEYVELERDE SALMONELLA TYPHIMURIUM’UN FAJLARLA BİYOKONTROLÜ(2024) Encu, Şeyma Betül; Yildirim, Aslı; Akbaş, Selin; Çakir, Ibrahim; Soykut, Esra AcarGıda kaynaklı hastalıklar dünya çapında halk sağlığı açısından büyük bir sorun olarak varlığını sürdürmektedir. Mikrobiyel kaynaklı gıda zehirlenmelerinin başında ise patojenik Salmonella serotipleri gelmektedir. Bu çalışmada dilimlenmiş meyvelerde de rastlanan Salmonella Typhimurium’un fajlar ile inhibisyonu hedeflenmiştir. Bunun için atık su, çiğ süt ve tavuk eti örneklerinden izole edilen Salmonella Typhimurium fajlarının EcoRV ve XbaI enzimleri ile RFLP analizi yapılmış 9 fajdan 4’ünün genomik olarak birbirinden farklı olduğu tespit edilmiştir. Tek aşamalı gelişme eğrileri çıkarılan bu fajların latent dönemleri kısa (5-15 dk), patlama büyüklükleri ise 25-111 PFU/hücre aralığında bulunmuştur. Fajların farklı cins bakterilere karşı litik etkisi incelenmiş fakat Salmonella dışındaki Gram pozitif ve Gram negatif bakterilere karşı litik etkisi saptanmamıştır. Fajlardan hazırlanan kokteyl ile kavunda S. Typhimurium sayısında MOI 1000 ve 10000 değerlerinde 2 log KOB/g azalış; ananas örneklerinde ise MOI 10 ve 100 değerlerinde 1 log KOB/g azalış tespit edilmiştir. Hazırlanan faj kokteylinin gıda endüstrisinde Salmonella kontrolü için kullanılabilecek stratejiler arasında olabileceği ortaya konmuştur.Öğe The use of bacteriophage cocktails to reduce Salmonella Enteritidis in hummus(ELSEVIER, 2022) Tayyarcan, Emine Kübra; Evran, Şefika; Akın, Pervin Arı; Soykut, Esra Acar; Boyacı, İsmail HakkıSalmonellosis is among the most common foodborne diseases. Despite the precautions taken at every stage of the production, several Salmonella outbreaks were associated with hummus which has started to become a popular food across the world. Phages are used for the biocontrol of food pathogens and have several benefits including being effective, specific and safe. In this study, the efficacy of two phages with three multiplicity of infection (10, 100, 1000) on the reduction of Salmonella Enteritidis in hummus during the storage at 4 degrees C and 10 degrees C was evaluated. The characterization of phages was performed by examining their host range, revealing their morphological features by using TEM, and determining replication parameters by using one-step growth and adsorption curves. After these procedures, they were applied to the hummus experimentally contaminated with S. Enteritidis. As a result, it was found that phages decreased Salmonella count by 2.30 and 3.23 log units at the end of 7-day storage at 4 degrees C and 10 degrees C, respectively. Additionally, phages did not significantly affect the texture and color of hummus. This paper has shown that phages could be used to reduce Salmonella counts in hummus without affecting the features that may influence its acceptability by the consumer.
