Oksidacija galne kiseline katalizirana lakazom u različitim reaktorskim sustavima (CROSBI ID 429429)
Ocjenski rad | diplomski rad
Podaci o odgovornosti
Šimunović, Roberto
Tišma, Marina
Ostojčić, Marta
hrvatski
Oksidacija galne kiseline katalizirana lakazom u različitim reaktorskim sustavima
Galna kiselina je netoksičan i u prirodi široko raspostranjen fenolni spoj. U bioprocesima kataliziranima lakazom može se koristiti kao supstrat za proizvodnju polikonjugiranih poluvodičkih polimera te u proizvodnji boja. U ovom radu istraživana je oksidacije galne kiseline katalizirana lakazom u različitim vrstama reaktora. Eksperimenti provedeni su u kotlastom reaktoru koristeći različite početne koncentracije galne kiseline, lakaze i kisika, te u ponovljivim šaržnim uvjetima (6 ciklusa). Reakcija je također istraživana u staklenom mikroreaktoru s ulaznim kanalima Y-oblika, unutarnjeg volumena 9, 5 µL i u mikroreaktoru s ugrađenim mikromikserom volumena 2 µL. Lakaza je kontinuiranim protokom ulazila na jedan, a galna kiselina na drugi ulaz u mikrokanal. Ispitivana su različita vremena zadržavanja (konstantni volumni protoci od 10, 30 i 50 µL / min), te različite koncentracije galne kiseline i lakaze. Na osnovu dobivenih rezultata pokazano je da lakaza ima visoku operativnu stabilnost u svim reaktorskim uvjetima. Nadalje, potvrđeno je da dolazi do inhibicije supstratom i da kisik nije limitirajući reaktant. U šaržnom reaktoru postignuta je 98% konverzija nakon 40 min (0, 1 mg / mL lakaze, 0, 1 mM galne kiseline). Vrijeme potrebno da se postigne ista konverzija smanjeno je na samo 15 min kada je koncentracija lakaze povećena pet puta. Značajno poboljšanje postignuto je u mikroreaktoru pri čemu je 44% konverzija galne kiseline postignuta nakon 29 s (0, 1 mg/mL lakaze, 0, 1 mM galne kiseline). Povećanjem koncentracije lakaze za 5 puta postignute su konverzije i do 99 %.
galna kiselina ; lakaza ; oksidacija ; mikroreaktor ; šaržni reaktor
nije evidentirano
engleski
Oxidation of Gallic Acid Catalyzed by Laccase in Different Reactors
Production of polyconjugated semiconducting polymers and dyes in laccase-catalyzed bioprocess. In this work the study of laccase-catalyzed oxidation of gallic acid in different reactor types was performed. Initial experiments were performed in a batch reactor using different initial concentrations of gallic acid, laccase and oxygen and in repetitive cycles experiments (6 cycles). The reaction was then investigated in a Y shaped glass microreactor with internal volume of 9.5 μL and microreactor with micromixer with initial volume of 2 μL. Laccase was fed from one inlet while gallic acid was fed from the other inlet. Different residence time (constant flow rates of 10, 30 and 50 μL/min), gallic acid and laccase concentrations were tested. Results have shown that laccase has high operational stability at all reactor conditions. Furthermore, it was confirmed that substrate inhibition occurs and oxygen is not a rate-limiting reactant. In a batch reactor, a 98% conversion was reached after 40 min (0.1 mg/mL laccase, 0.1 mM gallic acid). The conversion time was reduced to solely 15 min when the laccase was increased five fold. Significant conversion improvements were obtained in the microreactor with 44% conversion of gallic acid just after 29 s (0.1 mg/mL laccase, 0.1 mM gallic acid). Higher conversion, up to 99%, were obtained when the laccase was increased five fold.
galic acid ; laccase ; oxidation ; microreactor ; batch reactor
nije evidentirano
Podaci o izdanju
50
24.09.2019.
obranjeno
109:626325
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