Antioksidacijska aktivnost hidrofilnih i lipofilnih spojeva sortnog sjemena uljane repice

master's thesis

• Title (english): Antioxidative activity of hydrophylic and lypophylic compaunds of rapeseed
• Author: Branka Ferlak
• Mentor: Jasna Vorkapić-Furač (mentor)
• Granter: University of Zagreb; Faculty of Food Technology and Biotechnology; (Department of Biochemical Engineering); (Laboratory for Cell Technology, Application and Biotransformations); Zagreb
• Defense date and country: 2007-02-02, Croatia
• Scientific / art field, discipline and subdiscipline: BIOTECHNICAL SCIENCES; Biotechnology

Abstract

Sjeme uljane repice bogato je antioksidantima među kojima prevladavaju polifenolni spojevi, sinapin i sinapinska kiselina. Nakon preradbe sjemena polifenolni spojevi pretežito zaostaju u sačmi. Zbog antioksidacijske aktivnosti polifenola uljana se repica istražuje kao izvor antioksidanata, radi njihova korisnog djelovanja na ljudsko zdravlje te mogućnosti primjene u zaštiti prehrambenih proizvoda od kvarenja. U radu su u različitim sortama uljane repice analizirani ukupni polifenolni spojevi u metanolnim ekstraktima UV/VIS spektroskopskom metodom, uporabom Folin-Ciocalteau reagensa, a njihova antioksidacijska aktivnost UV/VIS spektroskopijom (DPPH-metoda) i spektrofluorimetrijom (ORAC-metoda). Uzorci s najvišom koncentracijom polifenola imaju najveću antioksidacijsku aktivnost određenu s obje metode. Antioksidacijski kapacitet određen je i u heksanskim ekstraktima ORAC-metodom modificiranom za lipofilne spojeve. Utvrđeno je da su antioksidanti prisutni i u lipofilnim ekstraktima, ali u mnogo manjoj količini nego u hidrofilnim ekstraktima.

Abstract (english)

Rapeseed is a rich source of antioxidants, among them the most frequent are polyphenols, sinapin and sinapic acid. After rapeseed modification polyphenols mostly stay in rapeseed meal. Because of their antioxidative activity rapeseed is studied as source of antioxidants because of their role in protecting human health and possibility to protect food from deterioration. In this paper the objective was to determine the total amount of polyphenols in methanol extracts with UV/VIS spectroscopy, using Folin-Ciocalteau reagent, and defining their antioxidative activity with UV/VIS spectroscopy (DPPH-method) and fluorescence spectroscopy (ORAC-method). The samples that contain the highest amount of polyphenols have the highest antioxidant activity, and their inhibition time of 50 % DPPH-radical activity is the lowest. Antioxidative capacity was also defined in hexane extracts using ORAC-method which was modified for lypophylic compounds. It was determined that polyphenols are also present in lypophylic extracts but in smaller amounts than in hydrophylic extracts.

• Keywords: antioksidativna aktivnost; DPPH-metoda; ORAC-metoda; polifenoli; uljana repica
• Keywords (english): antioxidantive activity; DPPH-method; ORAC-method; polyphenols; rapeseed
• Language: croatian
• URN:NBN: urn:nbn:hr:159:676333
• Study programme: Title: Biotechnology; specializations in: Biochemical Engineering; Course: Biochemical Engineering; Study programme type: university; Study level: graduate; Academic / professional title: diplomirani inženjer biotehnologije; smjer biokemijsko inženjerstvo (diplomirani inženjer biotehnologije; smjer biokemijsko inženjerstvo)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Access restricted to students and staff of home institution
• Created on: 2017-09-06 10:34:06