Primjena različitih metoda u određivanju antioksidacijskog kapaciteta ekstrakta kave

undergraduate thesis

• Title (english): Application of different assays in determination of antioxidative capacity of coffee extract
• Author: Ivana Cuki
• Mentor: Draženka Komes (mentor)
• Granter: University of Zagreb; Faculty of Food Technology and Biotechnology; (Department of Food Engineering); (Laboratory for Chemistry and Technology of Carbohydrates and Confectionery Products); Zagreb
• Defense date and country: 2011-09-15, Croatia
• Scientific / art field, discipline and subdiscipline: BIOTECHNICAL SCIENCES; Nutrition

Abstract

Kava je napitak koji, uz stimulirajući i diuretički učinak, ima brojne pozitivne učinke na ljudsko zdravlje, ukoliko se konzumira u ograničenim količinama te se stoga svrstava u funkcionalne napitke. Kava predstavlja bogati izvor bioaktivnih spojeva, posebice polifenola kao najpoznatijih antioksidansa. Cilj ovog rada je karakterizacija antioksidacijskog kapaciteta ekstrakata kave. U tu svrhu ispitano je 12 vrsta kave kojima je određen udio ukupnih fenola i antioksidacijski kapacitet. Udjel ukupnih fenola određen je reakcijom s Folin-Ciocalteu reagensom. Antioksidacijski kapacitet određen je reakcijama sa željezo(III)-tripiridiltriazina (FRAP), pomoću radikala 2,2'-azinobis (3–etilbenzotiazolin-6-sulfonske kiseline) (ABTS) i 1,1-difenil-2-pikrilhidrazil radikala (DPPH). Udjel polifenolnih spojeva, kao i antioksidacijski kapacitet ekstrakata kave ovise o vrsti i načinu pripreme ekstrakata. Potvrđena je dobra korelacija između rezultata svih metoda primjenjenih u radu.

Abstract (english)

Abstract: Coffe brew is known as a stimulant, property mainly attributed to caffeine: however, the number of chemical compounds identified in this beverage is large and some have many beneficial attributes in preventing some severe and prevalent diseases what justifies its classification as a functional beverage. Coffee represents a source of bioactive compounds, especially polyphenols which are one of the main antioxidants. The aim of this study was to examine antioxidative capacity of coffee extract. For that cause, 12 types of coffee were tested to determine a concentration of total phenols and antioxidative capacity. The concentration of total phenols was determined by using a reaction with Folin-Ciocalteu reagent while the antioxidative capacity was determined by using reactions with iron(III)-tripyridyilitrazine (FRAP)radical, 1,1-diphenyl-2-picrylhydrazyl radical (DPPH) and radicals 2,2'-azinobis (3–ethylbenzothiazoline-6-sulfonic acid) (ABTS). A good corelation has been confirmed between results that were tested in this study.

• Keywords: antioksidacijski kapacitet; ekstrakt kave; polifenoli
• Keywords (english): antioxidative capacity; coffee extract; polyphenols
• Language: croatian
• URN:NBN: urn:nbn:hr:159:162368
• Study programme: Title: Nutrition; Study programme type: university; Study level: undergraduate; Academic / professional title: sveučilišni/a prvostupnik/prvostupnica (baccalaureus/baccalaurea) nutricionizma (sveučilišni/a prvostupnik/prvostupnica (baccalaureus/baccalaurea) nutricionizma)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Access restricted to students and staff of home institution
• Created on: 2017-05-19 12:21:41