Production of B-Galactosidase using lactic acid bacteria and optimisation of fermentation parametters
tarafından
 
Üstok, Fatma Işık.

Başlık
Production of B-Galactosidase using lactic acid bacteria and optimisation of fermentation parametters

Yazar
Üstok, Fatma Işık.

Yazar Ek Girişi
Üstok, Fatma Işık.

Yayın Bilgileri
[s.l.]: [s.n.], 2007.

Fiziksel Tanımlama
xiii, 120 leaves.: ill.+ 1 computer laser optical disc.

Özet
Food grade thermostable B -galactosidase preparations are always in demand for a number of industrial applications. Thermostable -galactosidases from LAB having a neutral pH-optimum can be safely used to reduce the lactose content of milk for the lactose intolerant people. In this study, -galactosidase was produced with high productivities by novel Lactobacillus delbrueckii subsp. bulgaricus and Streptococcus thermophilus strains isolated from traditional Turkish yogurt samples in Toros mountain region. A full factorial statistical design was used separately for Lactobacillus delbrueckii subsp. bulgaricus and Streptococcus thermophilus strains in screening experiments. Among the strains, Lactobacillus delbrueckii subsp. bulgaricus 77 and Streptococcus thermophilus 95/2 were found to have high potential for B-galactosidase and lactic acid production, therefore these were used in the further optimisation studies.The efficiency of different cell disruption methods was investigated on the extraction of -galactosidase. Among these, lysozyme enzyme treatment was determined as the most effective method. Optimisation studies were carried out using response surface methodology to optimize fermentation conditions for pure strains as well as for mixed ones. Therefore, symbiotic relationship between St 95/2 and Lb 77 were investigated as well. Symbiotic relationship provided 39% and 6.1 % more -galactosidase activity and 44 % and 9.73 % more lactic acid production when compared to the optimisation results of pure strains Lb 77 and St 95/2, respectively.Overall, characterization studies showed that enzymes obtained from these strains can be considered as food grade and thermostable since they are obtained from thermophile, food originated novel LAB of local microflora.

Konu Başlığı
Lactic acid bacteria.
 
Lactose intolerance.
 
Lactobacillus.
 
Beta-galactosidase.
 
Fermentation.

Yazar Ek Girişi
Tarı, Canan

Tüzel Kişi Ek Girişi
İzmir Institute of Technology. Biotechnology and Bioengineering.

Tek Biçim Eser Adı
Thesis (Master)--İzmir Institute of Technology: Biotechnology and Bioengineering.
 
İzmir Institute of Technology: Biotechnology and Bioengineering--Thesis (Master).

Elektronik Erişim
Access to Electronic Version


LibraryMateryal TürüDemirbaş NumarasıYer NumarasıDurumu/İade Tarihi
IYTE LibraryTezT000654TP248.L3 U88 2007Tez Koleksiyonu