Nadêžda Vrchotová

Dr. Nadêžda Vrchotová


Research Focus & Metrics

Academic Career Length

15Years (2012-Present)

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

Representative Publications

View All Publications
8 April 2015 in Molecules
Verified
Journal Article
Open access
PDF file
ISIvo Soural
Ivo Soural
NVNadêžda Vrchotová
Nadêžda Vrchotová
JTJan Tříska
Jan Tříska
JBJosef Balík
Josef Balík
ŠHŠtěpán Horník
Štěpán Horník
JSJan Sykora
Jan Sykora
Grape cane, leaves and grape marc are waste products from viticulture, which can be used to obtain secondary stilbene derivatives with high antioxidant value. The presented work compares several extraction methods: maceration at laboratory temperature, extraction at elevated temperature, fluidized-bed extraction, Soxhlet extraction, microwave-assisted extraction, and accelerated solvent extraction. To obtain trans-resveratrol, trans-ε-viniferin and r2-viniferin from grape cane of the V. vinifera variety Cabernet Moravia, various conditions were studied: different solvents, using powdered versus cut cane material, different extraction times, and one-step or multiple extractions. The largest concentrations found were 6030 ± 680 µg/g dry weight (d.w.) for trans-resveratrol, 2260 ± 90 µg/g d.w. for trans-ε-viniferin, and 510 ± 40 µg/g d.w. for r2-viniferin. The highest amounts of stilbenes (8500 ± 1100 µg/g d.w.) were obtained using accelerated solvent extraction in methanol.

1 July 2020 in Food Chemistry
Verified
Journal Article
Closed access
JBJan Bedrníček
Jan Bedrníček
DJDana Jirotková
Dana Jirotková
JKJaromír Kadlec
Jaromír Kadlec
ILIvana Laknerová
Ivana Laknerová
NVNadêžda Vrchotová
Nadêžda Vrchotová
PSPavel Smetana
Pavel Smetana

5 November 2021 in Foods
Verified
Journal Article
Open access
PDF file
JBJan Bedrníček
Jan Bedrníček
ILIvana Laknerová
Ivana Laknerová
FLFrantišek Lorenc
František Lorenc
PMPriscila Probio de Moraes
Priscila Probio de Moraes
MJMarkéta Jarošová
Markéta Jarošová
PSPavel Smetana
Pavel Smetana
Black garlic (BG) is a product originating from fresh garlic (FG) and substantially differs in many aspects from FG due to the process called ageing. During this thermal process, the health-promoting properties of FG are enhanced, and the sensory traits are altered. However, very little is known about how the physicochemical properties of different FG varieties affect these properties of BG. Thus, the aim of this study was to investigate the influence of seven FG varieties subjected to the thermal process on the physicochemical parameters of BG. To prepare the BG samples, a fifteen-day ageing process involving a temperature gradient ranging from 30 to 82 °C was used. It was found that the antioxidant activity, the total polyphenol content, and the total soluble solids increased during ageing, while the pH level, moisture content, and lightness decreased in all the garlic varieties. The varieties of garlic differed in the studied traits significantly, both before (FG) and after ageing (BG). In the sensory analysis, significant differences between the BG varieties were observed only in the pleasantness of texture, while the remaining sensory descriptors (pleasantness of color, odor, taste and intensity of the garlic aroma, and overall acceptability) were not affected by variety. The correlations suggest that most of the FG’s studied parameters in this study do not correlate with the properties of BG and cannot be used for the prediction of the quality of BG. Additionally, HPLC-MS/MS analysis revealed substantial changes in the composition of low molecular compounds.

31 January 2023 in Nutrients
Verified
Journal Article
Open access
PDF file
MMMartin Magner
Martin Magner
KTKateřina Thorová
Kateřina Thorová
VŽVeronika Župová
Veronika Župová
Milan HouśkaMilan Houśka
Milan Houśka
IŠIvana Švandová
Ivana Švandová
LJLadislav Jílek
Ladislav Jílek
Autism spectrum disorder (ASD) is a pervasive neurodevelopmental disorder with repetitive behaviour which affects interaction and communication. Sulforaphane (SFN), an isothiocyanate abundant in the seeds and sprouts of cruciferous vegetables, has been shown to be effective in alleviating autistic behaviour. We performed a prospective double-blind placebo-controlled study to examine the possible effect of SFN in a paediatric cohort aged three to seven years based on measurements of the Autism Diagnostic Observation Schedule-2 (ADOS-2), the Social Responsiveness Scale-2 (SRS-2), and the Aberrant Behaviour Checklist (ABC). The study consisted of three visits over the duration of 36 weeks (baseline, 18 weeks, and 36 weeks). Twenty-eight of the 40 randomized children completed the study. The mean total raw scores on ABC and SRS-2 improved in both groups, but none of the changes reached statistical significance (ABC: 0 weeks p = 0.2742, 18 weeks p = 0.4352, and 36 weeks 0.576; SRS-2: 0 weeks p = 0.5235, 18 weeks p = 0.9176, and 36 weeks 0.7435). Changes in the assessment of the ADOS-2 subscale scores also did not differ between the two study cohorts (ADOS-2: 0 weeks p = 0.8782, 18 weeks p = 0.4788, and 36 weeks 0.9414). We found no significant clinical improvement in the behavioural outcome measures evaluated in children with ASD aged 3–7 years that were treated with sulforaphane.

14 October 2021 in Plants
Verified
Journal Article
Open access
PDF file
MŽMartin Žabka
Martin Žabka
Roman PavelaRoman Pavela
Roman Pavela
KKKateřina Kovaříková
Kateřina Kovaříková
JTJan Tříska
Jan Tříska
NVNadêžda Vrchotová
Nadêžda Vrchotová
JBJan Bednar
Jan Bednar
The antifungal and insecticidal effect of the essential oil from Ocimum sanctum L. was evaluated using a model set of harmful organisms hazardous for health and the economy. Toxigenic and plant pathogenic filamentous fungi, including causal agents of human infections, were chosen as exemplary fungal groups—Fusarium verticillioides, Penicillium expansum and Aspergillus flavus. Spodoptera littoralis (African cotton leafworm), Culex quinquefasciatus (Southern house mosquito), the lymphatic filariasis vector and potential Zika virus vector, and the common housefly, Musca domestica were chosen as model insects. Major and minor active substances were detected and quantified using GC/MS analysis. Environmental safety was verified using the non-target useful organism Eisenia fetida. Significant antifungal and insecticidal activity, as well as environmental safety, were confirmed. The essential oil showed the highest efficacy against A. flavus according to MIC50/90, and against S. littoralis larvae according to LD50/90. The monoterpenoid alcohol linalool, t-methyl cinnamate, and estragole as phenylpropanoids were detected as effective major components (85.4%). The essential oil from Ocimum sanctum L. was evaluated as universal and significantly efficient, providing a high potential for use in environmentally safe botanical pesticides.

19 August 2021 in Foods
Verified
Journal Article
Open access
PDF file
JTJan Tříska
Jan Tříska
JBJosef Balík
Josef Balík
Milan HouśkaMilan Houśka
Milan Houśka
PNPavla Novotná
Pavla Novotná
MMMartin Magner
Martin Magner
ISIvo Soural
Ivo Soural
Broccoli sprouts contain 10–100 times higher levels of sulforaphane than mature plants, something that has been well known since 1997. Sulforaphane has a whole range of unique biological properties, and it is especially an inducer of phase 2 detoxication enzymes. Therefore, its use has been intensively studied in the field of health and nutrition. The formation of sulforaphane is controlled by the epithiospecifier protein, a myrosinase co-factor, which is temperature-specific. This paper studies the influence of temperature, heating time, the addition of myrosinase in the form of Raphanus sativus sprouts in constant ratio to broccoli sprouts, and other technological steps on the final sulforaphane content in broccoli sprout homogenates. These technological steps are very important for preserving sulforaphane in broccoli sprouts, but there are some limitations concerning the amount of sulforaphane. We focused, therefore, on the extraction process, using suitable β-cyclodextrin, hexane and ethanol, with the goal of increasing the amount of sulforaphane in the final extract, thus stabilizing it and reducing the required amount sulforaphane needed, e.g., as a dietary supplement.