Ispitivanje utjecaja procesa aktivacije nosioca na efikasnost imobilizacije

master's thesis

• Title (english): Investigation of carrier activation on the immobilisation efficiency
• Author: Marina Punčec
• Mentor: Ana Vrsalović Presečki (mentor)
• Committee member: Ana Vrsalović Presečki (predsjednik povjerenstva)
• Committee member: Ana Lončarić Božić (član povjerenstva)
• Committee member: Marin Kovačić (član povjerenstva)
• Granter: University of Zagreb; Faculty of Chemical Engineering and Technology; Zagreb
• Defense date and country: 2020-07-16, Croatia
• Scientific / art field, discipline and subdiscipline: TECHNICAL SCIENCES; Chemical Engineering

Abstract

DERA (deoksiriboza-5-fosfat aldolaza) je enzim iz skupine aldolaza, izoliran iz životinjskog tkiva i mikroorganizama. Katalizira reakciju sinteze (3R, 5R)-6-kloro-3,5-dihidroksi heksanala (laktola), prekursora u proizvodnji statina, aldolnom adicijom dvije molekule acetaldehida i jedne molekule kloroacetaldehida. U navedenoj reakciji, znatno je izražena deaktivacija enzima, uzrokovana visokim koncentracijama aldehida u sustavu. Cilj ovog rada bio je imobilizirati enzim DERA-u na magnetske nanočestice obložene silikom u svrhu povećanja njezine stabilnosti u prisustvu aldehida, a zatim ispitati utjecaj procesa aktivacije nosioca na efikasnost imobilizacije. Ispitan je utjecaj dvaju reagensa za aktivaciju nosioca: benzokinona i sukcinid anhidrida, te temperature i pH - parametara koji imaju znatan utjecaj na proces imobilizacije. Prilikom imobilizacije, kao najbolje sredstvo za aktivaciju pokazao se benzokinon, a najveća efikasnost imobilizacije enzima DERA-e je postignuta pri temperaturi od 20 °C i pH 6.

Abstract (english)

DERA (deoxyribose-5-phosphate aldolase) is an enzyme from the aldolase group, isolated from animal tissue and microorganisms. It catalyses the synthesis of statin precursor, (3R, 5R) -6-chloro-3,5-dihydroxy hexanal (lactol) in the reaction of the aldol addition of two acetaldehyde and one chloroacetaldehyde. In this reaction, enzyme deactivation is significant and it's caused by high concentrations of aldehydes in the system. The aim of this work was to immobilise the enzyme DERA on silica-coated magnetic nanoparticles in order to increase its stability in the presence of aldehydes, and to examine the impact of the carrier activation process on the immobilisation efficiency. The influence of two activation agents was investigated: benzoquinone and succinic anhydride, as well as temperature and pH, which have a significant impact on immobilisation process. During immobilisation, benzoquinone proved to be the best activation agent, and the the highest efficiency of immobilisation process was achieved at the temperature of 20 °C and pH 6.

• Keywords: deoksiriboza-5-fosfat aldolaza; DERA; imobilizacija enzima; magnetske nanočestice; benzokinon; sukcinid anhidrid; deaktivacija enzima
• Keywords (english): deoxyribose-5-phosphate aldolase; DERA; enzyme immobilisation; magnetic nanoparticles; benzoquinone; succinic anhydride; enzyme deactivation
• Language: croatian
• URN:NBN: urn:nbn:hr:149:832279
• Study programme: Title: Chemical Engineering - Graduate study; Study programme type: university; Study level: graduate; Academic / professional title: magistar/magistra inženjer/inženjerka kemijskog inženjerstva (magistar/magistra inženjer/inženjerka kemijskog inženjerstva)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Open access; Embargo expiration date: 2021-07-01
• Created on: 2022-03-07 16:59:23