Radosevic K.,University of Zagreb |
Srcek V.G.,University of Zagreb |
Bubalo M.C.,University of Zagreb |
Rimac Brncic S.,University of Zagreb |
And 2 more authors.
Journal of Food Composition and Analysis | Year: 2017
Natural compounds isolated from vegetables have protective and disease-preventing potential for the development of functional food. This study investigates the in vitro antioxidant capacity, total polyphenol and total flavonoid content, glucosinolate and glucosinolate degradation products of broccoli and collard extracts. In vitro antitumor activities on two human tumour cell lines (MCF-7 and HeLa) were studied. Broccoli and collard extracts were extracted from fresh, blanched and boiled broccoli florets and collard leaves. The Oxygen Radical Absorbance Capacity (ORAC) assay revealed that collard extracts exhibited higher antioxidant capacity than broccoli extracts. Total polyphenol and total flavonoid contents were also higher in collard extracts. The extracts were compared for the contents of total glucosinolates, indol glucosinolates and aliphatic glucosinolates. Glucoraphanin was the predominant compound in total glucosinolate content, followed by glucobrassicin and neoglucobrassicin (95.97μmol 100g-1 fresh weight (fw), 85.42μmol 100g-1 fw and 82.12μmol 100g-1 fw, respectively) in broccoli extracts; while in collard extracts, the major glucosinolate was glucobrassicin (80.33μmol 100g-1 fw), followed by glucoiberin (67.50)μmol 100g-1 fw and sinigrin (21.91μmol 100g-1 fw). The strongest antiproliferative effect was observed in extracts obtained by blanching. The present study established that the extracts that were examined possess antioxidant and promising antitumour activities. © 2017 Elsevier Inc.
Nagy Z.,Szent Istvan University |
Daood H.,Szent Istvan University |
Koncsek A.,Rubin Paprika Processing Ltd |
Molnar H.,Food Science Research Institute |
Helyes L.,Szent Istvan University
Journal of Liquid Chromatography and Related Technologies | Year: 2017
From nutritional points of view, carotenoids, capsaicinoids, and tocopherols are valuable constituents in pungent peppers. A rapid and reliable high performance liquid chromatography (HPLC) method for the simultaneous determination of phytonutrients in spice red peppers and chili products was developed and validated. The method included simultaneous detection by fluorescence and diode-array detectors. The major capsaicinoids, two tocopherols and 43 carotenoid components, were simultaneously separated, detected, and identified in the appointed pepper powder (containing Capsicum annuum and Capsicum frutescens) for method validation. The separation was performed on a Nucleosil C18 reverse phase column and optimized gradient elution. Resolution ranged between 0.96 and 1.46 with the highest values corresponding to γ-tocopherol and α-tocopherol. The limits of detection and quantification of target compounds ranged between 18.77 and 148.08 ng mL−1. Recoveries were between 89.83–100.26 and 79.72–88.86% when standard materials were spiked at low and high amounts, respectively. The most sufficient extraction of the different phytonutrients was achieved by mixture of methanol and acetone, although it was only slightly better than the mixture of methanol and acetonitrile. These results suggest that the developed method could be used for rapid, one-step determination of a wide range of phytonutrients in chili and pepper powders. 2017 © Taylor & Francis
Boka B.,Eszterházy Károly College |
Korozs M.,Eszterházy Károly College |
Nanasi M.,Eszterházy Károly College |
Adanyi N.,Food Science Research Institute
Electroanalysis | Year: 2015
An enzyme-based amperometric biosensor was developed for the determination of the lysine content of pharmaceutical products, food and feed samples. Lysine decarboxylase (EC 18.104.22.168) from Bacterium cadaveris was coupled with diamine oxidase (EC 22.214.171.124) from Pisum sativum and horseradish peroxidase (EC 126.96.36.199). The enzymes were co-immobilized on a graphite electrode with an Os polymer. The biosensor worked in flow injection analysis system (FIA). Optimal working conditions were pH7.0 and -50mV potential vs. Ag/AgCl. The linear measuring range was 0.005-0.500mM. Different pharmaceutical products and feed samples were analysed by the lysine biosensor and by HPLC method for validation. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Csiffary G.,Eszterházy Károly College |
Futo P.,Eszterházy Károly College |
Adanyi N.,Food Science Research Institute |
Kiss A.,Food Science Research Institute
Food Technology and Biotechnology | Year: 2016
A novel biosensor for l-ascorbic acid determination in different beverages was elaborated. The ascorbate oxidase enzyme (AAO) from Cucurbita sp., EC 188.8.131.52, was immobilized on a screen-printed carbon electrode with poly(ethylene glycol) (400) diglycidyl ether (PEGDGE) as a crosslinking agent. The standards and samples were measured first with a blank electrode. An inert protein, bovine serum albumin (BSA), was immobilized on the surface of this electrode with PEGDGE. The BSA mass was equivalent to the mass of 10 U of AAO enzyme immobilized on the electrodes (0.021 mg). The linear measuring range for l-ascorbic acid was between 5 and 150 μmol/L. As l-ascorbic acid is a vital vitamin and a common antioxidant used in food industry, fruit juices and vitamin C effervescent tablets were examined. The results were compared to HPLC measurements.
PubMed | University of Parma, Maimónides University, Polytechnic Institute of Viseu, University of Zadar and 8 more.
Type: | Journal: Public health | Year: 2016
Dietary fibre (DF) is one of the components of diet that strongly contributes to health improvements, particularly on the gastrointestinal system. Hence, this work intended to evaluate the relations between some sociodemographic variables such as age, gender, level of education, living environment or country on the levels of knowledge about dietary fibre (KADF), its sources and its effects on human health, using a validated scale.The present study was a cross-sectional study.A methodological study was conducted with 6010 participants, residing in 10 countries from different continents (Europe, America, Africa). The instrument was a questionnaire of self-response, aimed at collecting information on knowledge about food fibres. The instrument was used to validate a scale (KADF) which model was used in the present work to identify the best predictors of knowledge. The statistical tools used were as follows: basic descriptive statistics, decision trees, inferential analysis (t-test for independent samples with Levene test and one-way ANOVA with multiple comparisons post hoc tests).The results showed that the best predictor for the three types of knowledge evaluated (about DF, about its sources and about its effects on human health) was always the country, meaning that the social, cultural and/or political conditions greatly determine the level of knowledge. On the other hand, the tests also showed that statistically significant differences were encountered regarding the three types of knowledge for all sociodemographic variables evaluated: age, gender, level of education, living environment and country.The results showed that to improve the level of knowledge the actions planned should not be delineated in general as to reach all sectors of the populations, and that in addressing different people, different methodologies must be designed so as to provide an effective health education.
PubMed | Eszterházy Károly College and Food Science Research Institute
Type: Journal Article | Journal: Food technology and biotechnology | Year: 2016
A novel biosensor for l-ascorbic acid determination in different beverages was elaborated. The ascorbate oxidase enzyme (AAO) from
Ferenczi S.,Food Science Research Institute |
Czukor B.,Food Science Research Institute |
Cserhalmi Z.,Food Science Research Institute
Periodica Polytechnica: Chemical Engineering | Year: 2014
In this study, combined microwave vacuum drying (MVD) with hot-air drying was evaluated, and then compared with hotair drying and freeze drying, by the quality of the created product. The aim was to show that MVD is a strong quality competitor with the conventional hot-air drying and the widely used, but expensive freeze drying. For raw material, Jonathan apple was used. The combined microwave vacuum drying consists of two steps, the hot-air pre-drying, and then the microwave vacuum drying. The MVD was made with a unique batch drying system. Chemical, (total phenolic compounds, free radical-scavenging activity, aromatic content) physical (hardness) and consumer-related (organoleptic, and microbiological) properties were measured as quality parameters. The results show that quality of the product made by MVD combined with hot-air pre-drying is higher than hot-air dried ones. By most of the measured quality parameters, microwave vacuum drying also provided higher quality product than freeze drying.
Szucs V.,Food Science Research Institute |
Szabo E.,Food Science Research Institute |
Banati D.,International Life science Institute
Elelmiszervizsgalati Kozlemenyek | Year: 2015
Partly because of consumer demand, and partly because of manufacturing and commercial aspects, our foods contain different additives, which is worrisome to some of the consumers. The goal of the present work was to study the level of knowledge related to additives, and the effect of the information provided in order to reduce the perceived risk. Results of our questionnaire survey showed that information has a beneficial effect on the consumer acceptance of food additives, and so credible and easy to understand information is extremely important for domestic consumers when making conscious decisions by. © 2015, Hungarian National Commiteee of the European Organization for quality. All rights reserved.
Szaloki-Dorko L.,Corvinus University of Budapest |
Szaloki-Dorko L.,Food Science Research Institute |
Steger-Mate M.,Corvinus University of Budapest |
Abranko L.,Corvinus University of Budapest
International Journal of Food Science and Technology | Year: 2016
Elderberry concentrate is widely used for food colouring. Its production includes several processing steps, which influence pigment composition, thus affecting the quality of final product. In this study, qualitative and quantitative changes in anthocyanin components were followed during the production of elderberry juice concentrate using Haschberg and Samocco varieties. Juice concentration resulted in more than five-fold concentration increase in anthocyanins; however, clarification, filtration and evaporation steps caused slight but continuous decrease in anthocyanins relative to the dry matter of the product. Pectolytic enzymatic treatment was found to be one of the most critical processing steps that affects anthocyanin yield during production, and this effect on yield can be variety-dependent. Additionally, two condensed dimeric anthocyanin species generated after heat treatment are reported for the first time to be present in elderberry juice concentrate. Our results suggest that cyanidin-based anthocyanin conjugates with more complex saccharide moieties are more robust during production. © 2016 Institute of Food Science and Technology.
PubMed | Agro Environmental Research Institute, MicroVacuum Ltd. and Food Science Research Institute
Type: | Journal: Food chemistry | Year: 2016
Optical waveguide lightmode spectroscopy (OWLS) technique has been applied to label-free detection of aflatoxin B1 in a competitive immunoassay format, with the aim to compare the analytical goodness of the developed OWLS immunosenor with HPLC and enzyme-linked immunosorbent assay (ELISA) methods for the detection of aflatoxin in spice paprika matrix. We have also assessed applicability of the QuEChERS method prior to ELISA measurements, and the results were compared to those obtained by traditional solvent extraction followed by immunoaffinity clean-up. The AFB1 content of sixty commercial spice paprika samples from different countries were measured with the developed and optimized OWLS immunosensor. Comparing the results from the indirect immunosensor to that obtained by HPLC or ELISA provided excellent correlation (with regression coefficients above 0.94) indicating that the competitive OWLS immunosensor has a potential for quick determination of aflatoxin B1 in paprika samples.