hrvatski jezikClear Cookie - decide language by browser settings

Bioactive compounds and antioxidant capacity of yellow Yinzhen tea affected by different extraction conditions

Mihelj, Tea; Belščak-Cvitanović, Ana; Komes, Draženka; Horžić, Dunja; Tomašić, Vlasta (2014) Bioactive compounds and antioxidant capacity of yellow Yinzhen tea affected by different extraction conditions. Journal of food and nutrition research, 53 (3). pp. 278-290. ISSN 1336-8672

[img]
Preview
PDF
Download (274kB) | Preview

Abstract

Tea is one of the most popular beverages consumed worldwide. Polyphenols in tea contribute to its health benefits possessing high antioxidant, anticarcinogenic and antiallergic activity. The aim of this study was to examine the effect of ethanol concentration, tea forms and storage duration on polyphenols and methylxanthines composition, as well as antioxidant capacity of yellow Yinzhen tea. Total polyphenol, flavonoid concentration and antioxidant capacity were measured spectrofotometrically, while individual catechins and methylxanthines were identified and quantified using high performance liquid chromatography with photodiode array detector (HPLC-PDA). •DPPH (reduction of 1, 1-diphenyl-2-picrylhidrazyl), ABTS•+ (reaction of 2, 2-azino-bis(3-ethylbenzthiazoline-6-sulphonic acid) and FRAP (reaction with iron(III)tripyridyltriazine) assays were applied to determine the antioxidant capacity. The highest polyphenol concentration and antioxidant capacity were determined in 75% ethanol tea extract stored for 24-hours. The application of lower ethanol concentration (50% or less) was the most efficient in individual catechins extraction. The most abundant catechin is epigallocatechin gallate, EGCG (12.60 ± 0.1 - 416.01 ± 2.70 mg•l-1), followed by the epigallocatechin, EGC (1.59 ± 0.10 - 264.92 ± 2.43 mg•l-1).

Item Type: Article
Uncontrolled Keywords: Yinzhen tea; ethanol; storage duration; polyphenols; methylxantines; HPLC-PDA
Subjects: BIOTECHNICAL SCIENCES > Food Technology
Divisions: Division of Physical Chemistry
Projects:
Project titleProject leaderProject codeProject type
Stability of alkaloids and polyphenols in food products of plant origin (Stabilnost alkaloida i polifenola u proizvodima biljnog podrijetla)-Draženka Komes058-0000000-3470MZOS
Depositing User: Tea Mihelj
Date Deposited: 30 Nov 2015 14:41
Last Modified: 19 Jan 2016 16:16
URI: http://fulir.irb.hr/id/eprint/2336

Actions (login required)

View Item View Item

Downloads

Downloads per month over past year