Bioaktivni peptidi nastali proteolitičkom aktivnošću soja Lactococcus lactis ZGBP5-32

master's thesis

• Title (english): Bioactive peptides made by proteolytic activity of Lactococcus lactis ZGBP5-32
• Author: Ana Tarandek
• Mentor: Blaženka Kos (mentor)
• Mentor: Ana Butorac (komentor)
• Mentor: Katarina Butorac (pomoć pri izradi, neposredni voditelj)
• Committee member: Andreja Leboš-Pavunc (predsjednik povjerenstva)
• Committee member: Ana Butorac (član povjerenstva)
• Committee member: Anita Slavica (član povjerenstva)
• 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: 2023-03-30, Croatia
• Scientific / art field, discipline and subdiscipline: BIOTECHNICAL SCIENCES; Biotechnology

Abstract

Cilj ovog diplomskog rada bio je identificirati i kvantificirati peptide s potencijalnim bioaktivnim djelovanjem koji nastaju razgradnjom kazeina u mlijeku pomoću proteolitičkog sustava bakterije Lactococcus lactis ZGBP5-32. Identifikacija i kvantifikacija peptida provedena je spregnutim tehnikama tekućinske kromatografije i spektrometrije masa. Kako bi se pratila proteolitička aktivnost tijekom fermentacije od 24 i 48 sati, analiziran je proteinski profil u uzorcima kromatografijom isključivanja prema veličini. Nakon 24 sata fermentacije u uzorcima je identificiran peptid KYIPIQYVLS kojem se pripisuje antioksidativno djelovanje, a nakon 48 sati fermentacije identificirani su bioaktivni peptidi KYIPIQYVLS, YQEPVLGPVRGPFPIIV, QEPVLGPVRGPFPIIV, VYPFPGPIPN, HQPHQPLPPT, RDMPIQAF i TKVIPYVRYL. U znanstvenoj literaturi za navedene peptide utvrđeno je i opisano antioksidativno, imunomodulatorno, antitrobinsko, antimikrobno i ACEinhibitorno djelovanje (Angiotensin-I-converting enzyme, ACE). Analizom proteinskog profila kromatografijom isključivanja prema veličini dokazano je da nakon 48 h inkubacije dolazi do znatnije proteolize proteina, a kvantitativnom analizom peptida dokazano je da nakon 48 h inkubacije statistički nastaje više bioaktivnih peptida nego nakon 24 h inkubacije što je rezultat produljenog vremena cijepanja peptidih veza u kazeinskoj strukturi.

Abstract (english)

The aim of this thesis was to identify and quantify peptides with potential bioactive effects that are produced by the degradation of casein in milk using the proteolytic system of the bacterium Lactococcus lactis ZGBP5 32. Peptide identification and quantification was carried out by combined techniques of liquid chromatography and mass spectrometry. In order to monitor the dynamics of the proteolytic activity during fermentation for 24 and 48 hours, the protein profile was analyzed by size exclusion chromatography. After 24 hours of fermentation, the peptide KYIPIQYVLS attributed to antioxidant activity was identified, and after 48 hours of fermentation, the bioactive peptides KYIPIQYVLS, YQEPVLGPVRGPFPIIV, QEPVLGPVRGPPFPIIV, VYPFPGPIPN, HQPHQPLPPT, RDMPIQAF and TKVIPYVRYL were identified. Antioxidant, immunomodulatory, antithrombin, antimicrobial and ACE-inhibitory effects have been determined and described in the scientific literature for the mentioned peptides. Analysis of the protein profile by size exclusion chromatography proved that after 48 h of incubation, more protein proteolysis occurs, and quantitative analysis proved that after 48 h of incubation, statistically more bioactive peptides are formed, which is the result of prolonged cleavage of peptide bonds in the casein structure.

• Keywords: bioaktivni peptidi; Lactococcus lactis ZGBP5-32; kazein; proteolitička aktivnost
• Keywords (english): bioactive peptides; Lactococcus lactis ZGBP5-32; casein; proteolytic activity
• Language: croatian
• URN:NBN: urn:nbn:hr:159:862341
• Study programme: Title: Molecular Biotechnology; Study programme type: university; Study level: graduate; Academic / professional title: magistar/magistra inženjer/inženjerka molekularne biotehnologije (magistar/magistra inženjer/inženjerka molekularne biotehnologije)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Open access
• Created on: 2024-05-21 11:32:12