Utjecaj ekstrakcijskih parametara na izolaciju ukupnih flavonoida, ukupnih flavonola i antioksidacijski kapacitet cvijeta i lista gloga

master's thesis

• Title (english): The influence of the extraction parameters on the isolation of total flavonoids, total flavonols and antioxidant capacity from flower and leaf of hawthorn
• Author: Katarina Hunjet
• Mentor: Verica Dragović Uzelac (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: 2015-09-21, Croatia
• Scientific / art field, discipline and subdiscipline: BIOTECHNICAL SCIENCES; Food Technology

Abstract

Svrha ovog istraživanja bila je odrediti optimalne uvjete ekstrakcije fenolnih spojeva iz biljne mješavine cvijeta i lista gloga (Crataegi folium cum flore). Ekstrakcija fenolnih spojeva provedena je primjenom ekstrakcije potpomognute mikrovalovima (MAE), uz upotrebu vodenih otopina etanola i metanola različitih udjela (30%, 50% i 70%, v/v), pri temperaturama 45°C, 55°C, 65°C, snagama mikrovalova od 150 do 300 W, kroz vrijeme ekstrakcije od 2 do 10 minuta. U ekstraktima gloga provedeno je određivanje ukupnih flavonoida, ukupnih flavonola te antioksidacijskog kapaciteta FRAP metodom. Najveći ekstrakcijski prinos za istraživane skupine fenolnih spojeva bio je kako slijedi: za ukupne flavonoide-15,07 mgQE/g (70% vodena otopina metanola, 8 minuta i 65°C), za ukupne flavonole-35,46 mgQE/g (70% vodena otopina etanola, 10 minuta i 55°C) te za antioksidacijski kapacitet 227,77 mgAAE/g (70% vodena otopina etanola, 6 minuta i 55°C).

Abstract (english)

The aim of this study was to determine the optimal conditions for the extraction of phenolic compounds from the flower and leaf of the hawthorn herbal mixture (Crataegi folium cum flore). The extraction of the phenolic compounds was performed using microwave assisted extraction ( MAE ), using different aqueous solution of ethanol and methanol (30% , 50% and 70% w,w) , at a temperature of 45°C, 55°C, 65°C and microwave power from 150 to 300 W, the extraction time of 2 to 10 minutes. Total flavonoids , flavonols and total antioxidant capacity by FRAP method were determined in hawthorn extracts. The highest yield of extraction of the phenolic compounds investigated were as follows : the total flavonoid - 15.07 mg QE/g (70% aqueous solution of methanol, 8 minutes and 65°C) , the total flavonols - 35.46 mgQE/g (70% aqueous solution of ethanol, 10 minutes and 55°C) and the antioxidant capacity of 227.77 mgAAE/g (70% aqueous solution of ethanol, 6 minutes and 55°C).

• Keywords: cvijet i list gloga; ekstrakcija potpomognuta mikrovalovima; flavonoidi; flavonoli; antioksidacijski kapacitet
• Keywords (english): flower and leaf of hawthorn; microwave assisted extraction; flavonoids; flavonols; antioxidant capacity
• Language: croatian
• URN:NBN: urn:nbn:hr:159:819329
• Study programme: Title: Nutrition; Study programme type: university; Study level: graduate; Academic / professional title: magistar/magistra nutricionizma (magistar/magistra nutricionizma)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Access restricted to students and staff of home institution
• Created on: 2017-05-02 10:21:58