Kateřina Valentová

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This study assessed the effect of an 8 week consumption of dried cranberry juice (DCJ) on 65 healthy young women. Basic biochemical and hematological parameters, antioxidant status, presence of metabolites in urine, and urine ex vivo antiadherence activity were determined throughout the trial. A 400 mg amount of DCJ/day had no influence on any parameter(More)
The fruit of Lonicera caerulea L. (blue honeysuckle; Caprifoliaceae) and its phenolic fraction were analyzed for nutrients and micronutrients. The phenolic fraction was prepared from berries percolated with 0.1% H3PO4 and SPE using Sepabeads SP207. The sugar and lipid content was analyzed by HPLC and GC-MS. The total content of anthocyanins was determined(More)
BACKGROUND & AIMS Yacon ( Smallanthus sonchifolius, Asteraceae) is a native Andean plant, cultivated for its tubers throughout South America. The leaves are used in folk medicine as a medicinal tea for hypoglycemia. This paper describes the antioxidant activity of various extracts from S. sonchifolius leaves for their content of phenolic components. (More)
Two selective acylation methods for silybin esterification with long-chain fatty acids were developed, yielding a series of silybin 7-O- and 23-O-acyl-derivatives of varying acyl chain lengths. These compounds were tested for their antioxidant (inhibition of lipid peroxidation and DPPH-scavenging) and anti-influenza virus activities. The acyl chain length(More)
Thin-layer chromatographic (TLC) screening of crude extracts of dried leaves and tubers of yacon (Smallanthus sonchifolius, Asteraceae) and products of acid hydrolysis of tubers on the silica gel HPTLC plates using the developing solvents ethyl acetate-formic acid-water (85:10:15, v/v/v) and n-hexane-ethyl acetate-formic acid (20:19:1, v/v/v) proved the(More)
The effect of Lonicera caerulea L. (blue honeysuckle) phenolic fraction (18.5% anthocyanins) on cell viability and against oxidative damage in low density lipoproteins (oxLDL), in rat microsomes and in primary cultures of rat hepatocytes and human umbilical vein endothelial cells (HUVEC), was tested. The phenolic fraction was nontoxic to rat hepatocytes and(More)
Radical scavenging and anti-lipoperoxidative effects of two organic fractions and two aqueous extracts from the leaves of a neglected Andean crop-yacon (Smallanthus sonchifolius Poepp. & Endl., Asteraceae) were determined using various in vitro models. The extracts' total phenolic content was 10.7-24.6%. They exhibited DPPH (IC50 16.14-33.39 microg/mL) and(More)
Smallanthus sonchifolius (yacon) and Lepidium meyenii (maca) were the traditional crops of the original population of Peru where they are also still used in folk medicine. These plants are little known in Europe and Northern America although at least yacon can be cultivated in the climatic conditions of these regions. This article deals with the botany and(More)
The flavonoid isoquercitrin (quercetin-3-O-β-d-glucopyranoside) is commonly found in medicinal herbs, fruits, vegetables and plant-derived foods and beverages. This article reviews the occurrence, preparation, bioavailability, pharmacokinetics, toxicology and biological activity of isoquercitrin and "enzymatically modified (α-glucosylated) isoquercitrin"(More)
This paper focuses on the biological and chemical variability of four yacon (Smallanthus sonchifolius) accessions cultivated under field conditions. Significant variations in tuber shape, weight, content of oligofructans, as well as in leaf isozymes, phenolics, and relative DNA contents were found. Accessions 6 and 88 were the most productive (up to 3.01(More)