3. FOOD ChEMISTRy & bIOTEChNOLOGy 3.1. Lectures
3. FOOD ChEMISTRy & bIOTEChNOLOGy 3.1. Lectures
3. FOOD ChEMISTRy & bIOTEChNOLOGy 3.1. Lectures
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Chem. Listy, 102, s265–s1311 (2008) Food Chemistry & Biotechnology<br />
P67 ANTIOxIDANT AND ANTIMuTAGENIC<br />
ACTIVITy OF DRIED FRuIT, DRuIT TEAS<br />
AND CEREAL FRuIT PRODuCTS<br />
IVAnA MáROVá a , MICHAELA BAROŠOVá a ,<br />
MARTInA TOMKOVá a , HEDVIKA VOnDRáČKOVá a ,<br />
KATEřInA DUROňOVá a and RADKA KOČí a<br />
a Institute of Food Science and Biotechnology, Brno University<br />
of Technology, Purkyňova 118, 612 00 Brno, Czech<br />
Republic,<br />
marova@fch.vutbr.cz<br />
Introduction<br />
Cereal products form important par of human nutrition.<br />
They contain high amount of saccharides, proteins, fiber,<br />
vitamins, minerals and other nutrients. There are many studies<br />
about benefitial healt effect of cereals in prevention of<br />
cardivascular diseases, cancer and hyperlipidaemia. At this<br />
time cereals are recommended mainly in the form of complex<br />
natural saccharides digested for a long time. Many cereals are<br />
mixed with other components as cocoa, nuts, seeds, hioney,<br />
chocolade, and also dried fruit. Addition of several kinds of<br />
dried fruit could enhance beneficial effect of cereal product.<br />
In this work some biologically active substances in dried<br />
fruit, fruit teas and cereal products were analyzed.<br />
Material and Methods<br />
8 kinds of fruit teas (apple, pear, black currant, lemone,<br />
cherry etc.) were erolled into this study. 14 kinds of dried fruits<br />
were analyzed (apple, pear, plum, berries, tropical kinds<br />
etc). 9 kinds of cereal müsli bars with addition of dried fruit<br />
(e.g. berries, bear, apple, pear, plum, orange etc.) were analyzed<br />
too.<br />
A n t i o x i d a n t A n a l y s i s<br />
Total phenolics were analyzed colometrically with Folin<br />
Ciocalteu reagent (750 nm). Total flavonoid content was analyzed<br />
colometrically with nanO 2 + AlCl 3 (510 nm).Total<br />
antioxidant capacity was measured by Randox kit.<br />
Individual flavonoids were analyzed by RP-HPLC/<br />
UV-VIS method. Using extrenal standards concentration<br />
of ((–)catechin, catechin gallate, chlorogenic acid, epicatechin,<br />
morin, quercetin, rutin was done. Samples (20 μl) were<br />
injected into the RP-18 column (Biospher PSI 200 C18, 7 μm,<br />
150 mm × 4.6 mm). Mobile phases were methanol/water<br />
(55 : 45) for catechins and methanol/acetonitrile/water + 1%<br />
phosporic acid (20 : 30 : 50) for flavonoid analysis. The flow<br />
rate was maintained at 0.75 ml min –1 , analysis was performed<br />
at 30 °C. Carotenoids (beta-carotene, lycopene, luteine) were<br />
analyzed by RP-HPLC with spectrophotometric detection<br />
using Hypersil C18, 5 μm, 250 mm × 4.6 mm column, isocratic<br />
elution by methanol at the flow rate 1.1 ml min –1<br />
and at 45 °C.<br />
Identifiaction of individual flavonoids and catechins was<br />
performed by on-line LC/MS/ESI analysis (Mass spectrometer<br />
LCQ Advantage Max). Optimalization of mass spectro-<br />
s722<br />
metry analysis in negative mode was done using chlorogenic<br />
acid. Samples of beer were mixed with 5 times higher amount<br />
of 2% HCl and extracted by SPE (Amid-2 column). Isocratic<br />
elution was performed by mobile phase acetonitrol:1% acetic<br />
acid 50 : 50 at flow rate 0.4 ml min –1 at 30 °C. Individual<br />
components were detected in full scan module.<br />
Ascorbic acid was determined usin RP-HPLC on Hypersil<br />
APS-2, nH2, 5 μm, 150 mm × 4.6 mm column. Samples<br />
were stabilized by 2% HPO 3 , 20 μl was injected. Mobile<br />
phase was natrium acetate/acetonitrile (95 : 5). Analysis was<br />
performed at flow rate 0.6 ml min –1 and 30 °C. Microtitration<br />
metod with 2,6-dichlorindofenol was used as comparative<br />
mthod too. The end point of titration was determined by pink<br />
colour.<br />
A n t i m u t a g e n i t y A s s a y<br />
Test strain Saccharomyces cerevisiae D7 was used for<br />
antimutagenic effect trstiny. The frequency of spontaneous<br />
convertants at the tryptophan locus (trp5-12/trp5-27) and<br />
revertants at the isoleucine locus (ilv-1-92/ilv1-92) was<br />
tested. In each assay positive and negative controls were<br />
included. For positive controls 4-nitroquinoline-1-oxide was<br />
used as standard mutagen. Experiments were carried out by<br />
1-day treatment of the growing cells with tested samles. After<br />
treatment the cells were washed with with phosphate buffer<br />
and plated on a solid medium. After 5-days cultivation<br />
at 28 °C Ile-revertants and Trp-convertants colonies were<br />
counted. Five consecutive experiments were performed.<br />
S e n s o r y A n a l y s i s<br />
A group of 21 respondents were enrolled into orientation<br />
sensory study. They tested several fruit tea and evaluated<br />
basic sensory parameters. The droup of respondents was divi-<br />
ded into two age-different groups:<br />
•<br />
•<br />
seniors: total 13, age 68.5 ± 7.16; 10 F/3 M,<br />
juniors: total 8, age 27.13 ± <strong>3.</strong>63; 6 F/2 M.<br />
Additionally, consumer questionnaire was completed<br />
by 35 student respondents. Preferences and consumption of<br />
dried fruit and cereal bars were evaluated.<br />
Results<br />
Analysis of dried fruits showed high level of vitamins<br />
and phenolics mainly in berries. High level of carotenoids<br />
was observed in dried apricots and plums. High antioxidant<br />
activity was found mainly in dried apples, cranberries and<br />
blueberries (Table I).<br />
The highest content of total phenolics, total flavonoids,<br />
total antioxidant capacity, procyanidin B2 and chlorogenic<br />
acid was measured in plums and blueberry bars (Table II).<br />
The highest level of reduced saccharides was evaluated in<br />
raspberry and cereal bars.<br />
Higher antixidant content was found in herbal teas than<br />
in fruit teas. Comparing bag teas with loose leaf teas higher<br />
antioxidant activity was shown in loose leaf teas. In all tea<br />
samples catechins – catechin, epicatechin, epicatechin gallate