Polifenolni spojevi sjemena uljane repice i njihova antioksidacijska aktivnost

master's thesis

• Title (english): Polyphenols in rapeseed and their antioxidative activity
• Author: Silvija Bosnar
• 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: 2006-07-07, Croatia
• Scientific / art field, discipline and subdiscipline: BIOTECHNICAL SCIENCES; Biotechnology

Abstract

Posljednjih je godina posebno zanimanje znanstvenika usmjereno prema prirodnim antioksidantima i njihovoj ulozi u zaštiti ljudskog zdravlja. Uljana repica je prema mnogim istraživanjima bogata antioksidantima i to polifenolima (sinapinskom kiselinom i sinapinom). U radu su primjenom UV/VIS spektroskopske metode kvantitativno određeni ukupni polifenolni spojevi u različitim sortama odmašćenog sjemena uljane repice, a UV/VIS spektroskopskom i spektrofluorimetrijskom metodom određena je njihova antioksidacijska aktivnost. Ukupni polifenoli određeni su Folin-Ciocalteau reagensom, dok su za određivanje antioksidacijske aktivnosti upotrijebljene DPPH- i ORAC-metoda. Antioksidacijska aktivnost sačme uljane repice veća je u uzorcima, koji imaju veću koncentraciju polifenola. Vrijeme 50 %-tne inhibicije DPPH˙ najmanje je u uzorku, koji sadrži najviše polifenola. ORAC metodom je utvrđeno da je antioksidacijska aktivnost veća u uzorcima, koji sadrže višu koncentraciju polifenola i najduže sprječavaju pad intenziteta fluorescencije.

Abstract (english)

In the past few years special interest of scientists was directed towards natural antioxidants and their role in protecting human health. According to research data rapeseed is a rich source of antioxidants due to polyphenols (sinapic acid and sinapin). The objective of this study was determination of total amount of polyphenols in different sorts of rapeseed, using UV/VIS spectroscopy, and defining their antioxidative activity with UV/VIS spectroscopy and Fluorescence spectroscopy. Total content of polyphenols was determined from defatted rapeseed by method using Folin-Ciocalteau reagent. For radical scavenging activity measurements DPPH-method was used. ORAC-method was used for measuring antioxidant inhibition of peroxyl radical. Antioxidative activity of rapeseed was higher in samples that have higher total amount of polyphenols. Inhibition time of 50 % DPPH-radical activity was the least in samples that contain the highest amount of polyphenols. By ORAC-method it was determined that rapeseed sorts with higher total amount of polyphenols have higher antioxidative activity and longer inhibit loss of fluorescence.

• Keywords: antioksidacijska aktivnost; DPPH-metoda; ORAC-metoda; polifenoli; uljana repica
• Keywords (english): antioxidative activity; DPPH-method; ORAC-method; polyphenols; rapeseed
• Language: croatian
• URN:NBN: urn:nbn:hr:159:412403
• Study programme: Title: Biotechnology; specializations in: Biochemical-Microbiology; Course: Biochemical-Microbiology; Study programme type: university; Study level: graduate; Academic / professional title: diplomirani inženjer biotehnologije; smjer biokemijsko-mikrobiološki (diplomirani inženjer biotehnologije; smjer biokemijsko-mikrobiološki)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Access restricted to students and staff of home institution
• Created on: 2017-09-07 12:08:25