Antioksidativna učinkovitost polarne in nepolarne frakcije nerafiniranih rastlinskih olj

Goričar, Saša (author), Cigić, Blaž (mentor)

Antioksidanti so snovi, ki preprečujejo oksidacijo drugih molekul. Najpogosteje jih najdemo v različnih živilih, predvsem v sadju in zelenjavi. Velikokrat jih dodamo živilom kot prehranska dopolnila. Najpomembnejši antioksidanti v rastlinskih oljih so predvsem različni analogi vitamina E, tokoferoli in tokotrienoli. Nekatera nerafinirana rastlinska olja pa vsebujejo tudi druge, bolj polarne antioksidante, kot so sezamol, pinoresinol, tirozol in hidroksitirozol ter njihove derivate, kjer se olja ekstrahirajo skupaj z vitaminom E. Namen magistrske naloge je bil določitev antioksidativnega potenciala različnih rastlinskih olj v polarni in nepolarni frakciji z DPPH v različnih topilih. DPPH metoda je ena najpogostejših metod za določanje antioksidativnega potenciala (AOP) olj. AOP smo analizirali v etilacetatu in mešanici alkoholov, ki je vsebovala kislinsko bazni par. Pri svojem delu smo uporabljali oljčno, sezamovo, laneno in sončnično olje. Ugotovili smo, da je bil prispevek polarne frakcije k AOP večji v oljčnem in sezamovem olju kot v lanenem in sončničnem olju. Prav tako je iz naših rezultatov razvidno, da je AOP polarne in nepolarne frakcije olj aditiven s skupnim AOP olj. DPHH metodo v mešanici alkoholov in kislinsko baznega para lahko uporabimo za hitro oceno vsebnosti tokoferolov v sončničnem in lanenem olju.

• Language: Slovenian
• Keywords: rastlinska olja, oljčno olje, sezamovo olje, laneno olje, sončnično olje, antioksidanti, vitamin E, tokoferoli, antioksidacijski potencial, določanje antioksidantov, polarni antioksidanti, nepolarni antioksidanti, analizne metode, DPPH, HPLC, Folin-Ciocalteu metoda
• Work type: Master's thesis/paper
• Typology: 2.09 - Master's Thesis
• Organization: BF - Biotechnical Faculty
• Publisher: [S. Goričar]
• Year: 2017
• PID: 20.500.12556/RUL-91408
• UDC: 664.34:547.56:543.631
• COBISS.SI-ID: 4766840
• Publication date in RUL: 05.04.2017

GORIČAR, Saša, 2017, Antioksidativna učinkovitost polarne in nepolarne frakcije nerafiniranih rastlinskih olj [online]. Master’s thesis. S. Goričar. [Accessed 14 April 2025]. Retrieved from: https://repozitorij.uni-lj.si/IzpisGradiva.php?lang=eng&id=91408

Secondary language

• Language: English
• Title: Antioxidant efficiency of polar and non-polar fractions of unrefined vegetable oils

Abstract

Antioxidants are substances, that prevent oxidization of other molecules. They can be found in various foods most commonly in vegetables and fruits. They are often added to food as food additives. The most important antioxidants in plant oils are various analogs of vitamin E, tocopherols and tocotrienols. Some unrefined plant oils also contain some other, more polar antioxidants, such as sesamol, pinoresinol, tyrosol and hydroxytyrosol and their derivates, that are extracted along with vitamin E into the oils. The aim of this master thesis was to determine the antioxidative potencial of different plant oils in polar and non-polar fraction with DPPH in various solvents. DPPH method is one of the most frequent methods for evaluation of antioxidant potential (AOP) of oils. AOP was analyzed in ethylacetate and in the mixture of alcohols containing acid base pair. We found out, that the contribution of polar fraction to the AOP was greater in olive and sesame oil than in linseed and sunflower oil. Our data also show, that the sum of AOP for polar and non-polar fraction is the same as the AOP of unfractionated oil. DPPH assay performed in the mixture of alcohols containing acid base pair can be applied for rapid estimation of tocopherol content in sunflower and linseed oils.

• Keywords: vegetable oils, olive oil, sesame oil, linseed oil, sunflower oil, antioxidants, vitamin E, tocopherols, antioxidant potential, determination of antioxidants, polar antioxidants, non-polar antioxidants, analitical methods, DPPH, HPLC, Folin-Ciocalteu method