Chaetomium erraticum dekstranaz enziminin karboksillenmiş çok duvarlı karbon nano tüpler üzerine adsorpsiyon yöntemi ile immobilizasyonu
[ X ]
Tarih
2024
Yazarlar
Dergi Başlığı
Dergi ISSN
Cilt Başlığı
Yayıncı
Siirt Üniversitesi
Erişim Hakkı
info:eu-repo/semantics/openAccess
Özet
Bu tez çalışmasında, Chaetomium erraticum dekstranazı (CED), karboksillenmiş çok duvarlı karbon nanotüpler (MWCNT-COOH) üzerine adsorpsiyon yöntemiyle immobilize edilmiştir. İmmobilizasyon tamponunun pH'sı ve derişimi, MWCNT-COOH miktarı ve immobilizasyon süresi optimize edilerek %100 immobilizasyon verimi ve % 168.01 aktivite verimi elde edilmiştir. İmmobilize CED (ICED) ve serbest CED (FCED)'in karakterizasyonu yapılmış ve immobilizasyon sonrasında CED'in optimum pH değeri 5.0'den 6.0'e yükselmiş ve optimum sıcaklık 50°C'ye düşmüştür. Ayrıca, Lineweaver-Burk grafiği kullanılarak FCED ve ICED'in kinetik sabitleri belirlenmiştir. Dekstran substratı kullanıldığında, FCED ve ICED'in Km değerleri sırasıyla 127.2 g/L ve 241.0 g/L olarak hesaplanmış, Vmax değerleri ise sırasıyla 598.8 µmol/ml.dk ve 970.9 µmol/ml.dk olarak bulunmuştur. Art arda tekrar edilen 20 kullanım sonrası ve optimum koşullarda 20 günlük depolama sonrası ICED'in başlangıç aktivitesinde azalma görülmmemiştir. Sonuç olarak, bu tez çalışmasında elde edilen yüksek aktivite verimi ile uzun kullanım ve depolama kararlılığına sahip olan ICED'in gıda endüstrisinde dekstranın hidrolizi ve dekstrandan IMO üretimi uygulamalarında kullanılabileceği söylenebilir.
In this thesis study, Chaetomium erraticum dextranase (CED) was immobilized onto carboxylated multi-walled carbon nanotubes (MWCNT-COOH) using the adsorption method. The immobilization buffer's pH and concentration, the amount of MWCNT-COOH, and the immobilization duration were optimized to achieve 100% immobilization efficiency and 168.01% activity yield. The characterization of immobilized CED (ICED) and free CED (FCED) was performed. After immobilization, the optimum pH value of CED rised from 5.0 to 6.0 ranges, while the optimum temperature dropped to 50°C. Additionally, the kinetic constants for FCED and ICED were determined using the Lineweaver-Burk plot. When dextran substrate was used, the Km values for FCED and ICED were calculated as 241.0 g/L and 127.2 g/L, respectively, while the Vmax values were 970.9 µmol/ml.min and 598.8 µmol/ml.min, respectively. A decrease in the initial activity of ICED was observed after 20 consecutive uses and 20 days of storage under optimum conditions. As a result, it can be said that ICED, which has high activity efficiency and long-term use and storage stability obtained in this thesis study, can be used in the hydrolysis of dextran and IMO production from dextran applications in the food industry.
In this thesis study, Chaetomium erraticum dextranase (CED) was immobilized onto carboxylated multi-walled carbon nanotubes (MWCNT-COOH) using the adsorption method. The immobilization buffer's pH and concentration, the amount of MWCNT-COOH, and the immobilization duration were optimized to achieve 100% immobilization efficiency and 168.01% activity yield. The characterization of immobilized CED (ICED) and free CED (FCED) was performed. After immobilization, the optimum pH value of CED rised from 5.0 to 6.0 ranges, while the optimum temperature dropped to 50°C. Additionally, the kinetic constants for FCED and ICED were determined using the Lineweaver-Burk plot. When dextran substrate was used, the Km values for FCED and ICED were calculated as 241.0 g/L and 127.2 g/L, respectively, while the Vmax values were 970.9 µmol/ml.min and 598.8 µmol/ml.min, respectively. A decrease in the initial activity of ICED was observed after 20 consecutive uses and 20 days of storage under optimum conditions. As a result, it can be said that ICED, which has high activity efficiency and long-term use and storage stability obtained in this thesis study, can be used in the hydrolysis of dextran and IMO production from dextran applications in the food industry.
Açıklama
Fen Bilimleri Enstitüsü, Gıda Mühendisliği Ana Bilim Dalı
Anahtar Kelimeler
Gıda Mühendisliği, Food Engineering
