Biotehnološka proizvodnja bakterijskih sojeva Lactobacillus brevis D6 I Lactobacillus fermentum D12

master's thesis

• Title (english): Biotechnological production of bacterial strains Lactobacillus brevis D6 and Lactobacillus fermentum D12
• Author: Ema Balić
• Mentor: Jagoda Šušković (mentor)
• Granter: University of Zagreb; Faculty of Food Technology and Biotechnology; (Department of Biochemical Engineering); (Laboratory for Antibiotic, Enzyme, Probiotic and Starter Cultures Technology); Zagreb
• Defense date and country: 2018-03-29, Croatia
• Scientific / art field, discipline and subdiscipline: BIOTECHNICAL SCIENCES; Biotechnology

Abstract

Za probiotičke pripravke od iznimne je važnosti da sadrže žive stanice u koncentraciji većoj od 106 stanica po gramu proizvoda, jer jedino ako su prisutne u dovoljnoj količini mogu izazvati pozitivne učinke kod potrošača. Cilj ovog rada je bio ispitati utjecaj različitih nosača za mikroinkapsulaciju na preživljavanje bakterijskih sojeva Lactobacillus brevis D6 i Lactobacillus fermentum D12. Od tri ispitana nosača, alginata, karagenana i kazeina s djelovanjem transglutaminaze, alginat se pokazao kao najbolji nosač pri čemu je smrtnost stanica nakon procesa mikroinkapsulacije iznosila 0,125 log jedinica za soj L. brevis D6, odnosno 0,27 log jedinica za soj L. fermentum D12. Zatim je ispitano djelovanje različitih lioprotektora na stanice liofilizirane u alginatu. Od svih ispitanih lioprotektora (laktoza, inulin, saharoza, sorbitol i obrano mlijeko) obrano mlijeko se pokazalo kao najbolji lioprotektor za oba soja. Na kraju istraživanja je ispitano preživljavanje liofiliziranih mikroinkapsuliranih sojeva u simulirani uvjetima gastrointestinalnog trakta. Oba soja su pokazala visoko preživljavanje, odnosno bilo ih je u koncentraciji višoj od 109 CFU mL-1.

Abstract (english)

It is crucial for probiotic preparations to contain at least 106 viable cells per gram of the product to be able to express their health benefits for the host. The aim of this thesis was to investigate the influence of different methods of microencapsulation on the survival of probiotic bacteria Lactobacillus brevis D6 and Lactobacillus fermentum D12. Hence, three different matrixes for microencapsulation were used (alginate, carrageenan and casein with enzyme transglutaminase) to determine the best one and the alginate has been shown as the best. After process of microencapsulation the number of live cells of Lactobacillus brevis D6 strain was reduced by 0.125 log CFU g-1 and of Lactobacillus fermentum D12 strain by 0.27 log CFU g-1. Moreover, it was investigated how different lioprotectors (lactose, inulin, sucrose, sorbitol and skim milk) influence on viability of cells and skim milk had best characteristics. Finally, survival rate of bacterial strains through simulated gastrointestinal tract was investigated. Both strains have shown high survival rate, respectively concentrations were more than 109 CFU mL-1.

• Keywords: bakterije mliječne kiseline; probiotici; mikroinkapsulacija; liofilizacija
• Keywords (english): lactic acid baterica; probiotics; microencapsulation; lyophilization
• Language: croatian
• URN:NBN: urn:nbn:hr:159:534417
• Study programme: Title: Bioprocess Engineering; Study programme type: university; Study level: graduate; Academic / professional title: magistar/magistra inženjer/inženjerka bioprocesnog inženjerstva (magistar/magistra inženjer/inženjerka bioprocesnog inženjerstva)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Open access
• Created on: 2019-11-28 09:54:25