Erzincan tulum peynirinden laktik asit bakterilerinin (LAB) izolasyonu, moleküler metotlarla tanımlanması ve ekzopolisakkarit (EPS) üretim potansiyellerinin genetik olarak belirlenmesi
Küçük Resim Yok
Tarih
2016
Yazarlar
Dergi Başlığı
Dergi ISSN
Cilt Başlığı
Yayıncı
Bayburt Üniversitesi
Erişim Hakkı
info:eu-repo/semantics/openAccess
Özet
Geleneksel fermente ürünlerin üretimde rol alan Laktik Asit Bakterileri (LAB)'nin endüstriyel anlamda starter olarak kullanılabilmeleri o ürünün tat, yapı, aroma gibi özelliklerini oluşturan biyokimyasal faaliyetlerindeki çeşitliliğe ve ilgili metabolitleri üretme yeteneklerine bağlıdır. LAB türlerinin fermantasyon sırasında in situ olarak ekzopolisakkaritleri (EPS) üretmeleri hem ürünün fizikokimyasal niteliklerinde önemli gelişimlere neden olur hem de üreten türün çevresiyle etkileşimi çerçevesinde fonksiyonel sonuçlar oluşturabilir. Bu bağlamda bu tezin amacı Erzincan Tulum peynirinden EPS üreticisi starter olabilecek LAB türlerini izole etmek, bu türlerde homopolimerik ve heteropolimerik eps genlerini açığa çıkarmak ve bu türlerin ürettikleri EPS'i karakterize etmektir. Bu tez kapsamında tulum peyniri örnekleri Erzincan ili merkezi ve köylerinden toplanmış ve LAB türleri izole edilerek tanımlanmıştır. Tulum peyniri örneklerinden Lactobacillus plantarum, Lactobacillus paracasei, Lactobacillus brevis, Weissella paramesenteroides, Lactococcus garvieae ve Lactobacillus crustorum suşları izole edilmiş ve bu türlerde eps genlerinin PCR ile tespiti tulum peyniri izolatlarının türlere göre değişmekle birlikte homopolimerik gtf geni ve heteropolimerik EPS genlerini taşıdığı gösterilmiştir. Yapılan EPS üretim testleri bu türlerde EPS üretim miktarının birbirine yakın olduğunu ortaya koymuştur. Ayrıca seçilen bu türlerin EPS üretim kabiliyetlerinin farklı besiyeri ortamında değiştiği görülmüştür. Tulum peyniri izolatlarının ürettiği şeker gruplarının ortaya konması açısından türler pastörize süt ve %3 laktozlu MRS broth da geliştirilmiş ve EPS izolasyonu gerçekleştirilmiştir. HPLC analizi tulum peyniri izolatlarının sadece glukoz içeren EPS ürettiklerini ortaya koymuştur. Bu sonuçlar geleneksel olarak üretilen Erzincan Tulum peyniri üretiminde rol alan türler açısından EPS üretiminin önemini ortaya koymaktadır.
The potential use of lactic acid bacteria (LAB) involved in the production of traditional fermented products as starter cultures depends on the diversity of their biochemical activities that play role on taste, structure, flavor properties of these products and their ability to produce relevant metabolites. The in situ exopolisaccharide (EPS) production characteristics of LAB during the fermentation both results in substantial improvement in the physicochemical properties of the final product and also play roles in the interaction of these species with their environement that may result in functional outcomes. In this respect, the aim of this thesis was to isolate LAB species with EPS production characteristics that might be the starter culture for Ezincan Tulum cheese productino, to investigate the presence of homopolymeric and heteropolymeric eps genes in these species and to characterize the EPS produced by these species. In this thesis, tulum cheese samples were collected from Erzincan and its villages and LAB species were isolated and identified from these cheeses. Lactobacillus plantarum, Lactobacillus paracasei, Lactobacillus brevis, Weissella paramesenteroides, Lactococcus garvieae and Lactobacillus crustorum strains were isolated from cheeses samples and PCR detection of eps genes in these species revealed the presence of both homopolymeric gand heteropolymeric eps genes in these species. The EPS production tests revealed that these species produced similar levels of EPS. It was observed that EPS prodcution levels of the selected straines altered in different media conditions. In order to reveal the sugar groups produced by tulum cheese isolates, these species were grown in pasteurized milk and MRS broth containinsg 3% lactose and EPSs were isolated. HPLC analysis of the EPSs revealed that all strains produced EPS that included only glucose. These results demonstrate the importance of EPS production in LAB species that have a significant impact on Erzincan Tulum cheese production.
The potential use of lactic acid bacteria (LAB) involved in the production of traditional fermented products as starter cultures depends on the diversity of their biochemical activities that play role on taste, structure, flavor properties of these products and their ability to produce relevant metabolites. The in situ exopolisaccharide (EPS) production characteristics of LAB during the fermentation both results in substantial improvement in the physicochemical properties of the final product and also play roles in the interaction of these species with their environement that may result in functional outcomes. In this respect, the aim of this thesis was to isolate LAB species with EPS production characteristics that might be the starter culture for Ezincan Tulum cheese productino, to investigate the presence of homopolymeric and heteropolymeric eps genes in these species and to characterize the EPS produced by these species. In this thesis, tulum cheese samples were collected from Erzincan and its villages and LAB species were isolated and identified from these cheeses. Lactobacillus plantarum, Lactobacillus paracasei, Lactobacillus brevis, Weissella paramesenteroides, Lactococcus garvieae and Lactobacillus crustorum strains were isolated from cheeses samples and PCR detection of eps genes in these species revealed the presence of both homopolymeric gand heteropolymeric eps genes in these species. The EPS production tests revealed that these species produced similar levels of EPS. It was observed that EPS prodcution levels of the selected straines altered in different media conditions. In order to reveal the sugar groups produced by tulum cheese isolates, these species were grown in pasteurized milk and MRS broth containinsg 3% lactose and EPSs were isolated. HPLC analysis of the EPSs revealed that all strains produced EPS that included only glucose. These results demonstrate the importance of EPS production in LAB species that have a significant impact on Erzincan Tulum cheese production.
Açıklama
Fen Bilimleri Enstitüsü, Gıda Mühendisliği Ana Bilim Dalı
Anahtar Kelimeler
Biyoteknoloji, Biotechnology ; Gıda Mühendisliği
