Oksidacija glukoze katalizirana enzimom glukoza dehidrogenaza u kotlastom reaktoru

undergraduate thesis

• Title (english): Oxidation of glucose catalyzed by glucose dehydrogenase in a batch reactor
• Author: Karla Čulo
• Mentor: Anita Šalić (mentor)
• Committee member: Anita Šalić (predsjednik povjerenstva)
• Committee member: Ana Vrsalović Presečki (član povjerenstva)
• Committee member: Ana Jurinjak Tušek (član povjerenstva)
• Granter: University of Zagreb; Faculty of Chemical Engineering and Technology; Zagreb
• Defense date and country: 2024-09-17, Croatia
• Scientific / art field, discipline and subdiscipline: TECHNICAL SCIENCES; Chemical Engineering

Abstract

U današnje vrijeme sve je veći jaz između energetskih potreba i ograničenih izvora energije kao što su to fosilna goriva. Zbog toga se sve više istražuju obnovljivi energenti kao što je to primjerice vodik. Vodik se smatra jednim od najperspektivnijih izvora energije budućnosti jer ima visok energetski prinos. Vodik proizveden iz bioloških izvora naziva se biovodik te danas predstavlja jedan od najzanimljivijih obnovljivih izvora energije. Jedan od načina proizvodnje biovodika je i enzimska konverzija glukoze u glukonsku kiselinu uz regeneraciju koenzima i paralelnu proizvodnju molekularnog vodika. U okviru ovog istraživanja provedena je oksidacija glukoze katalizirana enzimom glukoza dehidrogenaza (GDH) iz Pseudomonas sp. uz koenzim NAD+ u kotlastom reaktoru. U prvom dijelu istraživanja provedena je karakterizacija enzima GDH iz Pseudomonas sp. na način da su određeni temperaturni i pH optimum za provedbu reakcije, te je odabran najbolji pufer. Rezultati su pokazali kako je optimalna temperatura za provedbu reakcije 40 ℃, pH 7 te pufer 0,1 mol/L TRIS-HCl pH 7.
U drugom dijelu istraživanja ispitana je reakcijska kinetika oksidacije glukoze metodom početnih brzina te su procijenjeni kinetički parametri. Kinetika oksidacije glukoze katalizirane GDH iz Pseudomonas sp. opisana je dvosupstratnom Michaelis–Menteničinom kinetikom s inhibicijom supstratom i kompetitivnom inhibicijom produktom. Za reakciju provedenu u kotlastom reaktoru postavljen je odgovarajući reaktorski model, koji se sastojao od kinetičkog modela i bilanci tvari za sve komponente reakcijske smjese. Ocjena valjanosti modela provedena na dva seta nezavisnih eksperimenata.

Abstract (english)

In today's world, there is a growing gap between energy demand and limited energy sources such as fossil fuels. As a result, renewable energy sources such as hydrogen are increasingly being researched. Hydrogen is considered one of the most promising energy sources of the future, as it has a high energy yield. Hydrogen produced from biological sources is known as biohydrogen and is one of the most interesting renewable energy sources today. One way of producing biohydrogen is the enzymatic conversion of glucose into gluconic acid with the regeneration of coenzymes and the parallel production of molecular hydrogen. In this study, glucose oxidation, catalyzed by the enzyme glucose dehydrogenase (GDH) with the coenzyme NAD+ was carried out in a batch reactor. In the first part of the study, the characterization of the enzyme GDH was performed by determining the optimal temperature and pH for the reaction and selecting the best buffer. The results showed that the optimal temperature for the reaction is 40°C, pH 7, and the buffer is
0.1 mol/L TRIS-HCl pH 7. In the second part of the study, the reaction kinetics of glucose oxidation was investigated using the initial rate method, and the kinetic parameters were estimated. The kinetics of glucose oxidation catalyzed by GDH is described by two-substrate Michaelis-Menten kinetics with substrate inhibition and competitive product inhibition.
A suitable reactor model was developed for the reaction carried out in the batch reactor, consisting of a kinetic model and mass balances for all components of the reaction mixture. The validation of the model was evaluated using two sets of independent experiments.

• Keywords: glukoza dehidrogenaza; glukoza; kinetički parametri; kotlasti reaktor
• Keywords (english): glucose dehydrogenase; glucose; kinetic parameters; batch reactor
• Language: croatian
• URN:NBN: urn:nbn:hr:149:623757
• Project: Number: IP-2022-10-2175; Title: Integrirani mikrosustav za enzimatsku proizvodnju biovodika; Title: Integrated micro-system for enzymatic biohydrogen production; Acronym: MicroBioH2; Leader: Bruno Zelić; Jurisdiction: Croatia; Funder: Hrvatska zaklada za znanost; Funding stream: Research Projects
• Study programme: Title: Environmental Engineering - Undergraduate study; Study programme type: university; Study level: undergraduate; Academic / professional title: sveučilišni/a prvostupnik/prvostupnica (baccalaureus/baccalaurea) inženjer/inženjerka ekoinženjerstva (sveučilišni/a prvostupnik/prvostupnica (baccalaureus/baccalaurea) inženjer/inženjerka ekoinženjerstva)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Open access
• Created on: 2024-11-15 15:40:03