Optimization of reaction conditions of enzyme-catalyzed rhododendrol glycoside hydrolysis

master's thesis

• Title (croatian): Optimiranje reakcijskih uvjeta hidrolize rododendrol glikozida katalizirane enzimima
• Author: Antonia Habazin
• Mentor: Ana Vrsalović Presečki (mentor)
• Committee member: Ana Vrsalović Presečki (predsjednik povjerenstva)
• Committee member: Hrvoje Kušić (član povjerenstva)
• Committee member: Marin Kovačić (član povjerenstva)
• Granter: University of Zagreb; Faculty of Chemical Engineering and Technology; Zagreb
• Granter: University of Split; Faculty of Chemistry and Technology; Split
• Defense date and country: 2023-09-27, Croatia
• Scientific / art field, discipline and subdiscipline: TECHNICAL SCIENCES; Chemical Engineering

Abstract

Rhododendrol glycosides are found in birch bark and can serve as a starting substrate for the production of raspberry ketone, via a hydrolysis reaction by the enzyme glucosidase, producing the intermediates (R)- and (S)-rhododendrol, followed by oxidation to the desired product. Natural properties of raspberry ketone include its use in cosmetics and perfumes, its anti-inflammatory and antioxidant abilities, its ability to prevent cancer, and its ability to combat insulin resistance. In this study, β-glucosidase from almonds was used to facilitate the hydrolysis of rhododendrol glycoside (betuloside). Different types of reactors were used to carry out the reaction, including a batch, a repetitive batch and a continuous enzyme membrane reactor (EMR). The kinetics of the hydrolysis was described by single-substrate Michaelis-Menten kinetics. The reaction products, rhododendrol and glucose, were found to inhibit the reaction in a competitive manner. During the implementation of the process, deactivation of the enzyme occurred and was described by the second-order kinetics. A batch reactor and an EMR were used to set up and validate a mathematical model of the process. In batch reactors a conversion of 100% was achieved. The highest productivity and stability of the enzyme was obtained when the reaction was carried out in a continuous EMR.

Abstract (croatian)

Glikozidi rododendrola nalaze se u kori breze i mogu djelovati kao početni supstrat za proizvodnju ketona maline, reakcijom hidrolize pomoću enzima glukozidaze koja proizvodi međuprodukte (R)- i (S)-rododendrola, nakon čega slijedi oksidacija do željenog produkta. Prirodna svojstva ketona maline uključuju njegovu upotrebu u kozmetici i parfemima, njihove protuupalne i antioksidativne sposobnosti, njihovu sposobnost sprječavanja raka, borbe protiv inzulinske rezistencije. U ovom diplomskom radu, β-glukozidaza iz badema korištena je za kataliziranje reakcije hidrolize rododendrol glikozida (betulozida) pri čemu nastaju dva enantiomera rododendrola. Za provođenje reakcije korišteni su različiti tipovi reaktora, uključujući kotlasti reaktor, ponovljivi kotlasti reaktor i kontinuirani enzimski membranski reaktor (EMR). Kinetika reakcije je opisana jednosupstratnom Michaelis-Menten kinetikom. Utvrđeno je da produkti reakcije, rododendrol i glukoza, inhibiraju reakciju na kompetitivni način. Prilikom provedbe procesa uočena je deaktivacija enzima koja je opisana kinetikom drugog reda. Kotlasti reaktor i EMR korišteni su za postavljanje i validaciju matematičkog modela procesa. U kotlastim reaktorima dobivena je konverzija supstrata od 100%. Najveća produktivnost i stabilnost enzima postignuta je prilikom provođenja reakcije u kontinuiranom EMR.

• Keywords: rhododendrol glycosides; betuloside; hydrolysis; β-glucosidase from almonds; batch reactor; enzyme membrane reactor; raspberry ketone
• Keywords (croatian): rododendrol glikozidi; betulosid; hidroliza; β-glukozidaza iz badema; kotlasti reaktor; enzimski membranski reaktor; keton maline
• Language: english
• URN:NBN: urn:nbn:hr:149:267066
• Project: Number: 101000560; Title: Rapid discovery and development of enzymes for novel and greener consumer products; Acronym: RADICALZ; Leader: Zvjezdana Findrik Blažević; Jurisdiction: eu; Funder: EC; Funding stream: H2020
• Study programme: Title: Chemical and environmental technology - graduate - university; Study programme type: university; Study level: graduate; Academic / professional title: sveučilišni/a magistar/magistra inženjer/inženjerka kemijskog inženjerstva (sveučilišni/a magistar/magistra inženjer/inženjerka kemijskog inženjerstva)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Embargoed access; Embargo expiration date: 2025-10-01
• Created on: 2023-11-22 11:01:39