master's thesis
Assessing the influence of coumarin on laccase inhibition

Marija Škarica (2012)
Josip Juraj Strossmayer University of Osijek
FACULTY OF FOOD TECHNOLOGY
Department of Process Engineering
Sub-department of Thermodynamics and Reaction Engineering
Metadata
TitleIstraživanje utjecaja različitih kumarina na inhibiciju lakaze
AuthorMarija Škarica
Mentor(s)Marina Tišma (thesis advisor)
Abstract
Cilj ovog rada bio je razviti kinetički model oksidacije ABTS‐a i L‐DOPE katalizirane lakazom u puferu i smjesi pufer/DMSO, istražiti utjecaj inhibicije različitih derivata kumarina na aktivnost lakaze, te odrediti tip inhibicije, postaviti kinetički model, procijeniti kinetičke parametre i validirati model koristeći različite koncentracije inhibitora. Provedbom oksidacije ABTS‐a i L‐DOPE pokazano je da enzim lakaza pokazuje veću specifičnu aktivnost na ABTS i L‐DOPU u vodenom mediju (VmABTS = 2964,59 ± 104,93 U mg‐1, Vm L‐DOPA = 13,14 ± 1,09 U mg‐1) u odnosu na specifičnu aktivnost navedenih spojeva u otopini koja sadrži organsko otapalo (VmABTS = 1974,26 ± 122,53 U mg‐1, Vm L‐DOPA = 9,58 ± 2,29 U mg‐1). Ispitivanjem inhibicijskog učinka derivata kumarina koristeći ABTS kao supstrat pokazan je inhibicijski učinak svih sedam ispitivanih derivata kumarina. Ispitivanjem inhibicijskog učinka derivata kumarina koristeći L‐DOPU kao supstrat pokazan je inhibicijski učinak samo tri derivata kumarina. Pokazano je da su Schiffove baze I‐2 i I‐3 najbolji inhibitori lakaze u pokusima u kojima je korišten ABTS kao supstrat.
KeywordsABTS method enzyme enzyme inhibition laccase L‐DOPA Schiff base tiosemocarbazide
Parallel title (English)Assessing the influence of coumarin on laccase inhibition
Committee MembersMilan Čačić
Marina Tišma
Ivica Strelec
Mirela Planinić
GranterJosip Juraj Strossmayer University of Osijek
FACULTY OF FOOD TECHNOLOGY
Lower level organizational unitsDepartment of Process Engineering
Sub-department of Thermodynamics and Reaction Engineering
PlaceOsijek
StateCroatia
Scientific field, discipline, subdisciplineBIOTECHNICAL SCIENCES
Food Technology
Engineering
Study programme typeuniversity
Study levelgraduate
Study programmeProcess Engineering
Academic title abbreviationmag. ing. proc.
Genremaster's thesis
Language Croatian
Defense date2012-11-15
Parallel abstract (English)
The aim of the study was development of a kinetic model for the oxidation of ABTS and L‐DOPA catalyzed by laccase in the buffer and buffer/DMSO mixture, to determine inhibitory effects of seven coumarin derivates on laccase activity, and to determine the type of inhibition, set a kinetic parameters and to validate the model using different concentations of inhibitors. The application of the oxidation of ABTS and L‐DOPA has shown that enzyme laccase shows a higher specific activity on ABTS and L‐DOPA in aqueous media (VmABTS = 2964,59 ± 104,93 U mg‐1, Vm L‐DOPA = 13,14 ± 1,09 U mg‐1) in comparison to specific activity of the mentioned compounds in a solution containing an organic solvent (Vm ABTS = 1974,26 ± 122,53 U mg‐1, Vm L‐DOPA = 9,58 ± 2,29 U mg‐1). Examining the inhibitory effect of coumarin derivatives using ABTS as substrate demonstrated the inhibitory effect of all seven coumarin derivatives. Examining the inhibitory effect of coumarin derivatives using L‐DOPA as substrate demonstrated the inhibitory effect of only three coumarin derivatives. It was shown that the Schiff bases I‐2 and I‐3 are the best inhibitors of laccase in experiments in which ABTS was used as substrate.
Parallel keywords (Croatian)ABTS metoda enzimi inhibicija enzima lakaza L‐DOPA Schiffove baze tiosemikarbazidi
Resource typetext
Access conditionAccess restricted to students and staff of home institution
Terms of usehttp://rightsstatements.org/vocab/InC/1.0/
URN:NBNhttps://urn.nsk.hr/urn:nbn:hr:109:268075
CommitterSanda Hasenay