Rapid estimation of tocopherol content in linseed and sunflower oils-reactivity and assay

Prevc, Tjaša (avtor), Levart, Alenka (avtor), Kralj Cigić, Irena (avtor), Salobir, Janez (avtor), Poklar Ulrih, Nataša (avtor), Cigić, Blaž (avtor)

The reactivity of tocopherols with 2,2-diphenyl-1-picrylhydrazyl (DPPH) was studied in model systems in order to establish a method for quantifying vitamin E in plant oils. The method was optimized with respect to solvent composition of the assay medium, which has a large influence on the course of reaction of tocopherols with DPPH. The rate of reaction of α-tocopherol with DPPH is higher than that of γ-tocopherol in both protic and aprotic solvents. In ethyl acetate, routinely applied for the analysis of antioxidant potential (AOP) of plant oils, reactions of tocopherols with DPPH are slower and concentration of tocopherols in the assay has a large influence on their molar reactivity. In 2-propanol, however, two electrons are exchanged for both α- and γ-tocopherols, independent of their concentration. 2-propanol is not toxic and is fully compatible with polypropylene labware. The chromatographically determined content of tocopherols and their molar reactivity in the DPPH assay reveal that only tocopherols contribute to the AOP of sunflower oil, whereas the contribution of tocopherols to the AOP of linseed oil is 75%. The DPPH assay in 2-propanol can be applied for rapid and cheap estimation of vitamin E content in plant oils where tocopherols are major antioxidants.

• Jezik: Angleški jezik
• Ključne besede: plant oil, α-tocopherol, γ-tocopherol, vitamin E, DPPH, antioxidants, solvent
• Vrsta gradiva: Članek v reviji
• Tipologija: 1.01 - Izvirni znanstveni članek
• Organizacija: BF - Biotehniška fakulteta ; FKKT - Fakulteta za kemijo in kemijsko tehnologijo
• Status publikacije: Objavljeno
• Različica publikacije: Objavljena publikacija
• Leto izida: 2015
• Št. strani: Str. 14777-14790
• Številčenje: Vol. 20, iss. 8
• PID: 20.500.12556/RUL-83386
• UDK: 664.3:577.161.3:544.4
• ISSN pri članku: 1420-3049
• DOI: 10.3390/molecules200814777
• COBISS.SI-ID: 4555896
• Datum objave v RUL: 17.08.2016

Gradivo je del revije

• Naslov: Molecules
• Skrajšan naslov: Molecules
• Založnik: MDPI
• ISSN: 1420-3049
• COBISS.SI-ID: 18462981

Licence

• Licenca: CC BY 4.0, Creative Commons Priznanje avtorstva 4.0 Mednarodna
• Povezava: http://creativecommons.org/licenses/by/4.0/deed.sl
• Opis: To je standardna licenca Creative Commons, ki daje uporabnikom največ možnosti za nadaljnjo uporabo dela, pri čemer morajo navesti avtorja.
• Začetek licenciranja: 13.08.2015

Sekundarni jezik

• Jezik: Slovenski jezik
• Ključne besede: rastlinska olja, sončnično olje, laneno olje, antioksidanti, tokoferol, vitamin E, antioksidativni potencial, kemijska kinetika