Fenolni spojevi te antioksidacijski kapacitet borovnice (Vaccinium corymbosum L.) tijekom berbe

master's thesis

• Author: Ivana Kovačević
• Mentor: Verica Dragović- Uzelac (mentor)
• Granter: University of Zagreb; Faculty of Food Technology and Biotechnology; (Department of Food Engineering); (Laboratory for Technology of Fruits and Vegetables Preservation and Processing); Zagreb
• Defense date and country: 2007-12-07, Croatia
• Scientific / art field, discipline and subdiscipline: BIOTECHNICAL SCIENCES; Food Technology

Abstract

Ukupni antocijani, ukupni fenoli, flavonoidi i neflavonoidi četiriju sorata borovnice kao i njihov antioksidacijski kapacitet bio je praćen u tri termina berbe. Ukupni sadržaj antocijana odeđen je spektrofotometrijskom metodom izbjeljivanja bisulfitom, dok su ukupni fenoli, flavonoidi i neflavonoidi određivani kolornom reakcijom sa Folin- Ciocolaten reagensom. Ukupna antioksidativna aktivnost borovnice određivana je trima metodama׃ uporabom 2,2'-azinobis(3- etilbenzotiazolin)-6-sulfonska kiselina) radikala (ABTS), redukcijom željozovog iona (FRAP) te uporabom 2,2-difenil-1-pikrilhidrazil (DPPH) radikala. Količine svih istraživanih skupina fenolnih spojeva nisu se ujednačeno mijenjale tijekom sukcesivnog perioda berbe. Antocijani su u najvećoj količini određeni u sorti Sierra u prvom i trećem periodu berbe. Najveće količine ukupnih fenola određene su u sortama Bluecrop i Eliot i to u prvom periodu berbe. U ukupnoj količini fenolnih spojeva prevladavali su spojevi iz skupine neflavonoida i to u značajnim količinama.

Abstract (english)

The total anthocyanins, total phenolics, total flavonoids and total nonflavonoids of four blueberry cultivars (Vaccinium corymbosum L.) as well as the corresponding antioxidant capacity were investigated during three time harvesting. The total anthocyanin content in blueberry fruits was determined by bisulphate bleaching method, while the quantities of total phenolics, flavonoids and non-flavonoids were determined by using Folin-Ciocalteu colorimetric method. Total antioxidant capacity of blueberry fruits was determined by using three methods: 2,2-azinobis(3- ethylbenzothiazoline-6-sulfonic acid) radical cation assay (ABTS), ferric ion reducing antioxidant power assay (FRAP), 2,2-diphenil-1-picrylhydrazyl radical scavenging capacity assay (DPPH). The amounts of all investigated group of poliphenols were not changed uniformly during successive period of harvesting. The higher amounts of anthocyanins in cultivar Sierra at 1st and 3rd harvesting period were observed whereas the highest amounts of total phenols in cultivar Bluecrop and Elliot in 1st harvesting period were determined. The predominant group of phenolic compounds in all investigated cultivars at all harvesting period were nonflavonoids.

• Keywords: antioksidacijski kapacitet; ukupni antocijani; ukupni fenoli; ukupni flavonoidi; ukupni neflavonoidi
• Keywords (english): antioxidant capacity; total anthocyanins; total flavonoids; total nonflavonoids; total phenolic
• Language: croatian
• URN:NBN: urn:nbn:hr:159:105131
• Study programme: Title: Food Technology; specializations in: Food Engineering; Course: Food Engineering; Study programme type: university; Study level: graduate; Academic / professional title: diplomirani inženjer prehrambene tehnologije; smjer prehrambeno inženjerstvo (diplomirani inženjer prehrambene tehnologije; smjer prehrambeno inženjerstvo)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Access restricted to students and staff of home institution
• Created on: 2017-09-05 11:14:31