master's thesis
Isolation, purification and partial characterization of apple polyphenol oxidase

Irena Janković (2014)
Josip Juraj Strossmayer University of Osijek
FACULTY OF FOOD TECHNOLOGY
Department of Applied Chemistry and Ecology
Sub-department of Biochemistry and Toxicology
Metadata
TitleIzolacija, pročišćavanje i djelomična karakterizacija polifenol oksidaze iz jabuka
AuthorIrena Janković
Mentor(s)Ivica Strelec (thesis advisor)
Abstract
Polifenol oksidaza je izolirana iz jabuka sorte Idared uz stupanj pročišćenja od 9,7 i iskorištenje 61,61 %. Postupak pročišćavanja uključivao je taloženje amonijevim sulfatom, taloženje acetonom i sušenje acetonskog taloga u struji dušika pri 24 °C. Enzim je pokazivao pH optimum pri pH 7, i optimalnu temperaturu djelovanja pri 24 °C uz L-3,4-dihidroksifenilalanin kao supstrat. Od ispitanih supstrata, polifenol oksidaza je pokazala najveću aktivnost uz katehin, a potom uz epikatehin, 4-metilkatehol , klorogensku kiselinu, L-3,4- dihidroksifenilalanin, kafeinsku kiselinu te epigalokatehingalat. Najboljim inhibitorima polifenol oksidaze pokazali su se glutation, askorbinska kiselina i cistein.
Keywordsisolation characterization polyphenol oxidase purification apple
Parallel title (English)Isolation, purification and partial characterization of apple polyphenol oxidase
Committee MembersDajana Gašo-Sokač
Ivica Strelec
Marina Tišma
Lidija Jakobek
GranterJosip Juraj Strossmayer University of Osijek
FACULTY OF FOOD TECHNOLOGY
Lower level organizational unitsDepartment of Applied Chemistry and Ecology
Sub-department of Biochemistry and Toxicology
PlaceOsijek
StateCroatia
Scientific field, discipline, subdisciplineBIOTECHNICAL SCIENCES
Food Technology
Engineering
Study programme typeuniversity
Study levelgraduate
Study programmeFood Technology and Process Engineering
Academic title abbreviationdipl. ing.
Genremaster's thesis
Language Croatian
Defense date2014-12-19
Parallel abstract (English)
Polyphenol oxidase was purified from the apple variety Idared with 9.7-fold purification and 61.61% recovery by ammonium sulphate precipitation, acetone precipitation and drying of acetone precipitate under gentle stream of nitrogen at 25 °C. Optimum polyphenol oxidase activity was at pH 7.0, and optimum temperature for activity was at 24 °C, both determined with L-3,4-dihydroxyphenylalanine as substrate. Of the substrates tested, activity was greatest with catechin followed by 4-methylcatechol, chlorogenic acid, L-3,4-dihydroxyphenylalanine, caffeic acid and epigallocatechin gallate. The most effective inhibitors tested were glutathione, ascorbic acid and cysteine.
Parallel keywords (Croatian)izolacija karakterizacija polifenol oksidaza pročišćavanje jabuka
Resource typetext
Access conditionOpen access
Terms of usehttp://rightsstatements.org/vocab/InC/1.0/
URN:NBNhttps://urn.nsk.hr/urn:nbn:hr:109:537991
CommitterSanda Hasenay