Yazar "Kaya, Halil İbrahim" seçeneğine göre listele
Listeleniyor 1 - 4 / 4
Sayfa Başına Sonuç
Sıralama seçenekleri
Öğe Diversity of Clostridium spp. causing late blowing in Kaşar cheese and their behaviour against various antimicrobials(Elsevier Ltd, 2023) Kaya, Halil İbrahim; Şimşek, Ömer; Akgunoglu, OzlemOne of the problems encountered during storage of Kaşar cheese is blowing. The diversity of Clostridium spp. having a role in blowing was screened and the sensitivity of Clostridium spp. strains against nisin, NaCl, CuSO4, and EDTA was determined and compared. According to 16S rDNA sequence similarity, 12 Clostridium spp. isolates were Clostridium sporogenes while 3 were Clostridium jeddahense. Gas formation by Clostridium spp. spores can be significantly inhibited by reducing the pH below 5.5 and adding 400 IU mL?1 nisin when the number of spores are below 300 spore mL?1. It was determined that the late-blowing problem in Kaşar cheese is caused by C. sporogenes and C. jeddahense strains, but the success of preventive agents is closely related to the amount of spores. © 2022 Elsevier LtdÖğe Isolation and Identification of Bacteriocin Producers from Bayburt Local Fermented Dairy and Characterization of Bacteriocins(2025) Kaya, Halil İbrahimLactic acid bacteria (LAB) have antimicrobial activity, in addition to other antimicrobial agents, mainly due to the bacteriocins that they produce. Using bacteriocins in the production of foods has considerable contributions to improving food safety and extending shelf life. One of the essential characteristics of bacteriocins is that they have structural variations according to the variety of producers and, accordingly, they have different antimicrobial activity spectrums. Therefore, new bacteriocins still need to be investigated and characterized. In this study, bacteriocin-producing LAB were isolated from the local fermented dairy of Bayburt and these bacteria were identified. The antimicrobial spectrum of bacteriocin-producing strains was then determined and their sensitivity to different temperatures and enzymes was characterized. Bacteriocin-producing LAB were identified as Lactobacillus plantarum, Pediococcus pentosaceus and Enterococuus faecium, respectively. These strains were found to be antibacterial against 7, 6 and 4 different indicators, respectively. All bacteriocins produced by LAB were found to lose their bacteriocin-derived activity when treated with proteolytic enzymes and to be in protein structure. They were found to be stable after 100 oC for 10 minutes, 80 oC for 10 minutes and 80 oC for 15 minutes heat treatment, respectively, they retained their antimicrobial activity.Öğe TARHANADAN İZOLE EDİLEN LAKTOBASİLLER TARAFINDAN ÜRETİLENBAKTERİYOSİNLERİN KARAKTERİZASYONU(2020) Kaya, Halil İbrahim; Şimşek, ÖmerTarhana Anadolu’da kış için hazırlanan ve sık tüketilen fermente bir gıdadır. Fermente tarhana hamuru laktik asit bakterileri (LAB) ve maya türlerinden oluşan mikrofloraya sahiptir. Bu florada bazı LAB’de bakteriyosin üretimiyle antimikrobiyal aktivite gösterirler. Çalışmamızın amacı tarhanadan izole edilmiş L. namurensis PFC70, L. plantarum PFC74 ve L. paralimentarius PFC97 suşlarının bakteriyosinlerinin belirlenmesi ve karakterizasyonudur. PFC70, PFC74 ve PFC97 suşlarının Micrococcus luteus DSM1790 suşuna karşı 400, 1600, 1600 AU/mL antimikrobiyal aktiviteye sahip olduğu belirlenmiştir. Suşların kültür üst sıvılarındaki metabolitlerin yüksek sıcaklığa ve proteaz enzimlerine karşı hassas, düşük pH koşullarında stabil, bakteriyosin tabiatında olduğu anlaşılmıştır. Üretici hücrelerin genomunda yapılan PZR taramasında, PFC74 bakteriyosininin plantarisin benzeri olduğu belirlenmiştir. Bakteriyosinler, amonyum sülfat çöktürmesi, katı faz ekstraksiyonu ve ters faz sıvı kromotografisi ile saflaştırılmış ve trisin-SDS PAGE ile moleküler büyüklükleri 5 kDa altında olduğu tespit edilmiştir. PFC70 vePFC74 bakteriyosini bakteriyosidal, PFC97 ise bakteriyostatik etkili bulunmuştur. Bu sonuçlar PFC70 suşunun yeni bir bakteriyosin üreticisi olduğunu göstermiştir.Öğe The effect of heart failure on gut microbial richness and diversity(Sociedade Portuguesa de Cardiologia, 2023) Kiliç, Oğuz; Kaya, Halil İbrahim; Seçme, Mucahit; Kilinç, Mehmet; Sevgi?Can, Cihan Ilyas; Buber, Ipek; Kiliç, Ismail Do?uIntroduction and objective: With recent advances in genome sequencing technology, a large body of evidence has accumulated over the last few years linking alterations in microbiota with cardiovascular disease. In this study, we aimed to compare gut microbial composition using 16S ribosomal DNA (rDNA) sequencing techniques in patients with coronary artery disease (CAD) and stable heart failure (HF) with reduced ejection fraction and patients with CAD but with normal ejection fraction. We also studied the relationship between systemic inflammatory markers and microbial richness and diversity. Methods: A total of 40 patients (19 with HF and CAD, 21 with CAD but without HF) were included in the study. HF was defined as left ventricular ejection fraction <40%. Only stable ambulatory patients were included in the study. Gut microbiota were assessed from the participants’ fecal samples. The diversity and richness of microbial populations in each sample were assessed by the Chao1-estimated OTU number and the Shannon index. Results: The Chao1-estimated OTU number and Shannon index were similar between HF and control groups. There was no statistically significant relationship between inflammatory marker levels (tumor necrosis factor-alpha, interleukin 1-beta, endotoxin, C-reactive protein, galectin-3, interleukin 6, and lipopolysaccharide-binding protein) and microbial richness and diversity when analyzed at the phylum level. Conclusion: In the current study, compared to patients with CAD but without HF, stable HF patients with CAD did not show changes in gut microbial richness and diversity. At the genus level Enterococcus sp. was more commonly identified in HF patients, in addition to certain changes in species levels, including increased Lactobacillus letivazi. © 2023
