Peter Nemeček

Dr. Peter Nemeček

Department of chemistry, Faculty of natural sciences, University of SS. Cyril and Methodius in Trnava
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Research Focus & Metrics

Academic Career Length

16Years (2011-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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15 December 2020 in Plants
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MHMichaela Havrlentová
Michaela Havrlentová
VGVeronika Gregusová
Veronika Gregusová
SSSvetlana SLIKOVA
Svetlana SLIKOVA
PNPeter Nemeček
Peter Nemeček
MHMartina Hudcovicová
Martina Hudcovicová
DKDominika Kuzmová
Dominika Kuzmová
In human nutrition, oats (Avena sativa L.) are mainly used for their dietary fiber, β-D-glucans and protein content. The content of β-D-glucans in oat grain is 2–7% and is influenced by genetic and/or environmental factors. High levels of this cell walls polysaccharide are observed in naked grains of cultivated oat. It the work, the relationship between the content of β-D-glucans in oat grain and the infection with Fusarium graminearum (FG) and Fusarium culmorum (FC) was analyzed. The hypothesis was that oats with higher content of β-D-glucans are better protected and the manifestation of artificial inoculation with Fusarium strains is weaker. In the 22 oat samples analyzed, the content of β-D-glucans was 0.71–5.06%. In controls, the average content was 2.15% for hulled and 3.25% for naked grains of cultivated oats. After the infection, a decrease was observed in all, naked, hulled and wild oats. As an evidence of lower rate of infection, statistically significant lower percentage of pathogen DNA (0.39%) and less deoxynivalenol (DON) mycotoxin (FC infection 10.66 mg/kg and FG 4.92 mg/kg) were observed in naked grains compared to hulled where the level of pathogen DNA was 2.09% and the average DON level was 21.95 mg/kg (FC) and 5.52 mg/kg (FG).

7 October 2021 in Microorganisms
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MHMichaela Havrlentová
Michaela Havrlentová
SSSvetlana SLIKOVA
Svetlana SLIKOVA
VGVeronika Gregusová
Veronika Gregusová
BKBernadett Kovácsová
Bernadett Kovácsová
ALAndrea Lančaričová
Andrea Lančaričová
PHPeter Hozlár
Peter Hozlár
Adverse environmental conditions, such as various biotic and abiotic stresses, are the primary reason for decreased crop productivity. Oat, as one of the world’s major crops, is an important cereal in human nutrition. The aim of this work was to analyze the effect of inoculation with two species of the genus Fusarium on the selected qualitative parameters of oat grain intended for the food industry. Artificial inoculation caused a statistically significant decrease in the content of starch, oleic, linoleic, and α-linolenic acids in oat grains compared to the control. Moreover, artificial inoculation had no statistically significant effect on the content of β-D-glucans, total dietary fiber, total lipids, palmitic, stearic, and cis-vaccenic acids. An increase in the content of polyunsaturated fatty acids in oat grains was observed after inoculation. The most important indicator of Fusarium infection was the presence of the mycotoxin deoxynivalenol in the grain. The content of β-D-glucans, as a possible protective barrier in the cell wall, did not have a statistically significant effect on the inoculation manifestation in the grain.

30 June 2022 in Polymers
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PHPeter Hozlár
Peter Hozlár
VGVeronika Gregusová
Veronika Gregusová
PNPeter Nemeček
Peter Nemeček
SSSvetlana SLIKOVA
Svetlana SLIKOVA
MHMichaela Havrlentová
Michaela Havrlentová
Oat is an important natural source of β-D-glucan. This polysaccharide of the cell wall of selected cereals is known for a number of health-promoting effects, such as reducing the level of cholesterol in the blood serum, stabilizing the level of blood glucose, or enhancing immunity. β-D-glucan has positive effects in the plant itself. There is a lack of information available, but the storage capacity of the polysaccharide and its importance as a protective substance in the plant during mild forms of biotic and abiotic stress are described. The accumulation of β-D-glucan during the ontogenetic development of oats (Avena sativa L.) was determined in the present work. Two naked (Valentin, Vaclav) and two hulled (Hronec, Tatran) oat varieties were used. Samples of each plant (root, stem, leaf, panicle) were collected in four stages of the plant’s development (BBCH 13, 30, 55, 71). The average content of the biopolymer was 0.29 ± 0.14% in roots, 0.32 ± 0.11% in stems, 0.48 ± 0.13% in leaves and 1.28 ± 0.79% in panicles, respectively. For root and panicle, in both hulled and naked oat varieties, sampling date was the factor of variability in the content of β-D-glucan. In stems in hulled varieties and leaves in naked varieties, neither the sampling date nor variety influenced the polysaccharide content. The content of β-D-glucan in the leaves of hulled and naked varieties decreased during the first three stages of plant development, but in the stage of milk ripeness the amount increased. The decreasing trend during milk ripeness, was also observed in the roots of both hulled and naked oats. However, in the panicle of hulled and naked oat varieties, the content of β-D-glucan increased during plant growth. Due to practical applications of natural resources of β-D-glucan and isolated β-D-glucan is useful to know the factors influencing its content as well as to ascertain the behavior of the polysaccharide during plant development.

1 January 2013 in Chemical Papers
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PNPeter Nemeček
Peter Nemeček
JMJán Mocák
Ján Mocák
JLJozef Lehotay
Jozef Lehotay
KWKarel Waisser
Karel Waisser

31 January 2011 in Journal of Liquid Chromatography & Related Technologies
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PNPeter Nemeček
Peter Nemeček
JMJan Mocak
Jan Mocak
JLJozef Lehotay
Jozef Lehotay
KWKarel Waisser
Karel Waisser
Derivatives of 3-phenyl-2H-1,3-benzoxazine-2,4(3H)-dione (PBOD) have become important mainly as perspective antituberculotic drugs. Quantitative structure-retention relationship (QSRR) is used for predicting the HPLC retention factor of this group of compounds and optimal chromatographic conditions appropriate for this purpose are selected. Among many molecular properties utilizable as the QSRR descriptors, mainly, in silico variables are advantageous as they closely characterize the HPLC retention of the PBOD molecule. Additionally, they are available without a need of the compound synthesis, which is important in the first stage of development of the potential drug. Artificial neural networks (ANN) were successfully used as the basic modeling QSRR tools because their regression outputs allow a direct prediction of retention factors for different combinations of the stationary and mobile phases. To prevent overfitting in ANN calculations, a distinctive elimination step, reducing about 50% of initial variables, was necessary to assure a desirable QSRR performance. Thoroughly tuned ANN models enabled a very accurate prediction of the PBOD retention factors when using C18 stationary phase and acetonitrile/water or methanol/water mobile phase.

25 January 2021 in Separations
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PRPetra Ranušová
Petra Ranušová
Ildiko MatusikovaIldiko Matusikova
Ildiko Matusikova
PNPeter Nemeček
Peter Nemeček
A solid-phase extraction (SPE) procedure was developed for simultaneous monitoring of sixteen different phenolics of various polarity, quantified by high-performance liquid chromatography (HPLC). The procedure allowed screening the accumulation of intermediates in different metabolic pathways that play a crucial role in plant physiology and/or are beneficial for human health. Metabolites mostly involved in phenylpropanoid, shikimate, and polyketide pathways comprise chlorogenic acid, gentisic acid, vanillic acid, caffeic acid, protocatechuic acid, ferulic acid, rutin, quercetin, epicatechin, gallic acid, sinapic acid, p-coumaric acid, o-coumaric acid, vanillin; two rarely quantified metabolites, 2,5-dimethoxybenzoic acid and 4-methoxycinnamic acid, were included as well. The procedure offered low cost, good overall efficiency, and applicability in laboratories with standard laboratory equipment. SPE recoveries were up to 99.8% at various concentration levels. The method allowed for routine analysis of compounds with a wide range of polarity within a single run, while its applicability was demonstrated for various model plant species (tobacco, wheat, and soybean), as well as different tissue types (shoots and roots).