Enzimska razgradnja boja i bojila

master's thesis

• Title (english): Enzymatic degradation of stains and dyes
• Author: Sven Mujadžić
• Mentor: Tonči Rezić (mentor)
• Granter: University of Zagreb; Faculty of Food Technology and Biotechnology; (Department of Biochemical Engineering); (Laboratory for Biochemical Engineering, Industrial Microbiology and Malting and Brewing Technology); Zagreb
• Defense date and country: 2014-02-19, Croatia
• Scientific / art field, discipline and subdiscipline: BIOTECHNICAL SCIENCES; Biotechnology

Abstract

U predstavljenom radu istražen je potencijal 6 različitih oksidoreduktaza za specifično obezbojenje 207 industrijski važnih boja uključujući antrakinonske, azo, triarilmetanske i indigiodne kromofore. Korišteni enzimi su celobioza dehidrogenaza iz biljno-patogene gljive Sclerotium rolfsii, lakaze iz askomikota Botrytis aclada te iz bazidiomikota Trametes pubescens, glukoza oksidaza iz plijesni Aspergillus niger, glukoza dehidrogenaza iz Glomerella cingulate i peroksidaza hrena. Obezbojenje se promatralo pri kiselim, neutralnim i bazičnim uvjetima koristeći UV/vis spektroskopiju u pločama s 96 jažica. Apsorbancija većine ispitanih boja se reducirala za najmanje 50% unutar 48 sata inkubacije na sobnoj temperaturi. Najveći postotak obezbojenja je primijećen pri pH 4 kod većine korištenih enzima. Peroksidaza hrena je uspješno razgradila 79 od 175 boja otopljenih u vodi (45%), zatim lakaza iz T. pubescens (27%), lakaza iz B. Aclada (27%), celobioza dehidrogenaza (15%) te glukoza dehidrogenaza (5.7%). Glukoza oksidaza (4%) se pokazala najmanje uspješnom, što ukazuje da peroksid ima neznačajan učinak na kromofore. Najveća specifična enzimska aktivnost od 1590 i 1718 U/mg je izmjerena kod Acid Blue 45 s lakazom iz T. pubescens i peroksidazom hrena. Iz dobivenih rezultata se vidi da se s ograničenim brojem enzima može uspješno obezbojiti velika količina bojila. Toksični učinci bojila su ispitani na slatkovodnim algama da bi se mogao procijeniti njihov utjecaj na okoliš.

Abstract (english)

In the presented work 6 different oxidoreductases were investigated for their potential to specifically decolorize 207 industrially relevant dyes including anthraquinone-, azo-, trimethylmethane-, and indigo chromophores. Utilized enzymes were cellobiose dehydrogenase from the plant-pathogenic fungus Sclerotium rolfsii, laccases from the ascomycete Botrytis aclada and the basidiomycete Trametes pubescens, glucose oxidase from Aspergillus niger, glucose dehydrogenase from Glomerella cingulata and horseradish peroxidase. Decolorization was studied at alkaline, neutral or acidic pH using UV/vis spectroscopy in the 96-well plate format. Absorbances of most of the investigated dyes could be reduced by at least 50% within 48 hours of incubation at room temperature. Highest rates of decolorization were observed at pH 4 for most of the enzymes. Horseradish peroxidase efficiently degraded 79 out of 175 dyes diluted in water (45%) followed by laccase from T. pubescens (27%), laccase from B. aclada (27%), cellobiose dehydrogenase (15%) and glucose dehydrogenase (5.7%). Glucose oxidase (4%) was least successful, indicating that peroxide has little effect on the chromophores. Highest specific enzyme activities of 1590 and 1718 U/mg were achieved with Acid Blue 45 when reacted with laccase from T. pubescens and HRP. Our results show that with a limited number of enzymes a multitude of dyes can be effectively decolorized. Toxic effects of the dyes on freshwater algae were also studied to assess their environmental impact.

• Keywords: Bojila; obezbojenje; enzimi; katalitički parametri; toksičnost
• Keywords (english): Dyes; decolorization; enzymes; catalytic parameters; toxicity
• Language: english
• URN:NBN: urn:nbn:hr:159:863743
• Study programme: Title: Bioprocess Engineering; Study programme type: university; Study level: graduate; Academic / professional title: magistar/magistra inženjer/inženjerka bioprocesnog inženjerstva (magistar/magistra inženjer/inženjerka bioprocesnog inženjerstva)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Access restricted to students and staff of home institution
• Created on: 2017-05-03 09:03:49