Antioksidacijski potencijal ukupnih fenola izoliranih iz gloga (Crataegi folium cum flore) primjenom ultrazvuka

master's thesis

• Title (english): Antioxidant potential of hawthorn (Crataegi folium cum flore) total phenol extract obtained by ultrasound assisted extraction
• Author: Ana Ćužić
• Mentor: Branka Levaj (mentor)
• Granter: University of Zagreb; Faculty of Food Technology and Biotechnology; (Department of Food Engineering); (Laboratory for Technology of Fruits and Vegetables Preservation and Processing); Zagreb
• Defense date and country: 2016-09-30, Croatia
• Scientific / art field, discipline and subdiscipline: BIOTECHNICAL SCIENCES; Food Technology

Abstract

Cilj rada bio je odrediti optimalne uvjete ekstrakcije fenolnih spojeva iz cvijeta i lista gloga (Crataegi folium cum flore) primjenom ekstrakcije potpomognute ultrazvukom. Varirani su sljedeći uvjeti: vrijeme ekstrakcije (3, 6 i 9 minuta), amplituda ultrazvuka (50%, 75 % i 100 %) te vrsta i polarnost otapala (50 % i 70 % metanol i etanol). U ekstraktima dobivenim pri prethodno navedenim uvjetima određivani su ukupni fenoli, primjenom Folin Ciocalteu metode te antioksidacijska aktivnost pomoću DPPH i FRAP metode. Prema dobivenim rezultatima, najveći ekstrakcijski prinos ukupnih fenola bio je 95,66 mgGAE g-1 pri amplitudi 100 % uz upotrebu 70 % vodene otopine etanola i vrijeme ekstrakcije od 6 minuta. Najveća antioksidacijska aktivnost DPPH metodom postignuta je uz upotrebu 50 % vodene otopine metanola pri amplitudi 100 % u šestoj minuti ekstrakcije. Najveća antioksidacijska aktivnost FRAP metodom postignuta je uz upotrebu 70 % vodene otopine metanola, pri amplitudi 50 % u šestoj minuti ekstrakcije.

Abstract (english)

The aim of this study was to optimize procedure of ultrasound assisted extraction (UAE) of phenolic compounds from the flower and leaf of hawthorn (Crataegi folium cum flore). The following extraction conditions were varied 3, 6 and 9 min of extraction, duration the amplitude of ultrasound (50 %, 75 % and 100 %) and the type and polarity of the solvent (50% and 70% methanol and ethanol). According to mentioned conditions in extracts, total phenols were determined by Folin Ciocalteu method, antioxidant activity by DPPH and FRAP methods was determined. According to the results, the optimal parameters for the highest yield of phenolic compounds was 95,66 mgGAE g-1 at amplitude of 100 % using a 70 % aqueous methanol solution and during 6 minutes.The highest antioxidant activity determined by DPPH was achieved by use a 50 % aqueous solution of methanol at an amplitude of 100 % and the extraction time of 6 minutes. The highest antioxidant activity determined by FRAP was achieved by use a 70 % aqueous methanol, at amplitude of 50 % and extraction time of 6 minutes.

• Keywords: cvijet i list gloga; ukupni fenoli; ekstrakcija potpomognuta ultrazvukom; antioksidacijski kapacitet
• Keywords (english): hawthorn leaf and flower; total phenols; ultrasound assisted extraction; antioxidant capacity
• Language: croatian
• URN:NBN: urn:nbn:hr:159:302858
• Study programme: Title: Food Engineering; Study programme type: university; Study level: graduate; Academic / professional title: magistar/magistra inženjer/inženjerka prehrambenog inženjerstva (magistar/magistra inženjer/inženjerka prehrambenog inženjerstva)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Open access
• Created on: 2017-04-26 08:40:11