Analiza sastava bioaktivnih peptida uslijed enzimske aktivnosti Lactococcus lactis ZGBP5-51 primjenom spektrometrije masa

master's thesis

• Title (english): Analysis of the composition of bioactive peptides due to the enzymatic activity of Lactococcus lactis ZGBP5-51 using mass spectrometry
• Author: Ljiljana Zovko
• Mentor: Jasna Novak (mentor)
• Mentor: Ana Butorac (komentor)
• Mentor: Katarina Butorac (pomoć pri izradi, neposredni voditelj)
• Committee member: Blaženka Kos (predsjednik povjerenstva)
• Committee member: Ana Butorac (član povjerenstva)
• Committee member: Anita Horvatić (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: 2023-09-28, Croatia
• Scientific / art field, discipline and subdiscipline: BIOTECHNICAL SCIENCES; Biotechnology

Abstract

Cilj ovog diplomskog rada bila je analiza bioaktivnih peptida i aromatskih spojeva, za koje se pretpostavlja da se nakupljaju uslijed enzimske i metaboličke aktivnosti probiotičkog soja Lactococcus lactis ZGBP5-51. Primijenjenom metodom spregnute tehnike plinske kromatografije i spektrometrije masa identificirani su spojevi arome. Ustanovljeno je da su karboksilne kiseline najzastupljenija kemijska skupina u analiziranim uzorcima fermentiranog mlijeka. Osim karboksilnih kiselina, nakon primjene ZGBP5-51 u monokulturi ili u kombinaciji sa starter kulturom, identificirani su raznovrsni spojevi arome koji pripadaju ketonima, aldehidima, alkanima, fenolima, alkoholima, esterima, laktonima i sulfidima. Identifikacija bioaktivnih peptida provedena je spregnutom tehnikom tekućinske kromatografije i spektrometrije masa. Identificirani peptidi, prema literaturi, iskazuju niz bioloških aktivnosti, uključujući ACE inhibitorno, antikancerogeno, imunomodulatorno, antidijabetičko, antioksidativno te cink-vezujuće djelovanje. Ciljana analiza bioaktivnih peptida provedena je spregnutom tehnikom tekućinske kromatografije, višestrukog praćenja reakcije i spektrometrije masa. Ne postoji statistički značajna razlika između količine specifičnih peptida koju sintetiziraju korišteni bakterijski sojevi. Samo u napitku fermentiranom sa sojem ZGBP5-51 detektiran je peptid sekvence ARHPHPHLSFM iz κ-kazeina, s antioksidativnim učinkom.

Abstract (english)

The aim of this thesis was the analysis of bioactive peptides and aromatic compounds, which are assumed to accumulate due to the enzymatic and metabolic activity of the probiotic strain Lactococcus lactis ZGBP5-51. Aroma compounds were identified using the coupled technique of gas chromatography and mass spectrometry. It was found that carboxylic acids are the most represented chemical group in the analyzed samples of fermented milk. Besides carboxylic acids, various aroma compounds belonging to ketones, aldehydes, alkanes, phenols, alcohols, esters, lactones, and sulfides were identified after application of ZGBP5-51 in monoculture or in combination with starter culture. The identification of bioactive peptides was performed by a combined technique of liquid chromatography and mass spectrometry. According to the literature, the identified peptides show several biological activities, including ACE inhibitory, anticancer, immunomodulatory, antidiabetic, antioxidant, and zinc-binding activity. Targeted analysis of bioactive peptides was performed using the coupled technique of liquid chromatography, multiple reaction monitoring, and mass spectrometry. There is no statistically significant difference between the number of specific peptides synthesized by the used bacterial strains. A peptide sequence ARHPHPHLSFM from κ-casein with an antioxidant effect was detected only in the sample fermented with strain ZGBP5-51.

• Keywords: bioaktivni peptidi; aromatski spojevi; proteolitički sustav; kazein; Lactococcus lactis
• Keywords (english): bioactive peptides; aromatic compounds; proteolytic system; casein; Lactococcus lactis
• Language: croatian
• URN:NBN: urn:nbn:hr:159:801534
• 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: 2024-05-24 09:16:27