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Polyphenol composition and antioxidant capacity from different extracts of Aster scaber
No full textPhenolic contents and antioxidant capacities from different solvent extracts (petroleum ether, ethyl acetate, methanol, butanol and water) of Aster scaber leaf were investigated. Antioxidant activity was evaluated by three different methods, namely DPPH radical scavenging activity, reducing power assay and phosphomolybdenum activity. A total of twenty-three polyphenolic compounds were identified and quantified from A. scaber leaf extracts, including hydroxybenzoic acids, hydroxycinnamic acids, flavonols and other groups of phenolic compounds. Ultra high performance liquid chromatography (UHPLC) analysis of the leaf extract revealed that myricetin (4850.45 μg/g) was the most dominant flavonols, compared to quercetin and kaempferol. Caffeic acid was the dominant phenolic compound in A. scaber leaf extracts, it constituted about 104.20 μg/g, followed by gentisic acid (84.50 μg/g), gallic acid (61.05 μg/g) and homogentisic acid (55.65 μg/g). The total phenolic and flavonoid content was the highest in ethyl acetate extract (322.43 and 6.51 mg/g). The decreasing order of antioxidant activity among the A. scaber leaf extracts assayed through all the three methods was found to be ethyl acetate > butanol > methanol > petroleum ether > water extract
Regulation of the unbalanced redox state in a Schizosaccharomyces pombe tert-butyl hydroperoxide-resistant mutant
No full textThe one-gene mutation in the tert-butyl hydroperoxide-resistant mutant hyd1-190 of the fission yeast Schizosaccharomyces pombe led to a 4-fold increase in resistance to t-BuOOH and decreased specific concentrations of superoxide and total thiols in comparison with the parental strain hyd+. It suggested an unbalanced redox state of the cells, which induced continuously increased specific activities of glutathione peroxidase, glutathione reductase and glutathione S-transferase and decreased activities of the antioxidant enzymes superoxide dismutases and glucose-6-phosphate dehydrogenase to regulate the redox balance of the mutation-induced permanent, low-level but tolerable internal stress. These results may contribute to the understanding of internal, oxidative stress-related human diseases
Exaggerated activity of HPA axis in obese rats fed normocaloric liquid nutrition
No full textExperimental and clinical studies have shown alterations in activity of systems responsible for neuroendocrine stress response in obese individuals. Therefore we investigated the effect of palatable normocaloric liquid nutrition (Fresubin) on alterations in activity of the hypothalamic-pituitary-adrenal (HPA) axis in male Wistar rats of different developmental stages. Control rats (CON) received standard pellet chow all the time from weaning (21st day of age) to 150 days. Fresubin was administered throughout the experiment (LN), only in juvenility (from 21st to 90th day of age; LNJ) or only in adulthood (from 90th to 150th day of age; LNA). Body weight and energy intake were periodically monitored. Adrenal gland and fat tissue weight and plasma corticosterone levels (CORT) was determined after sacrification. Fresubin intake induced obesity in LN and LNA rats. In LN and LNA rats were observed elevated serum CORT levels, but only in LN rats with significant twofold increase compared to LNJ rats. However, the weight of adrenal glands did not differ between LN, LNJ and LNA experimental groups. Based on our results, we suggest, that obesity induced by Fresubin in LN and LNA rats is accompanied by increased HPA activity represented by elevated plasma CORT levels in these rats
Effects of ascorbic acid on some physiological changes of pepino (Solanum muricatum Ait.) under chilling stress
No full textIn this study, the changes caused by chilling stress on some physiological parameters of pepino (Solanum muricatum Ait.) plant and the effects of ascorbic acid (100 mM) applied exogenously on these changes were examined. For this purpose, the photosynthetic pigments (chlorophyll a, chlorophyll b, total chlorophylls and carotenoids), ascorbic acid, total phenolic compounds, malondialdehyde and proline contents in leaves of pepino taken on 5th and 10th days were determined. As a result of chilling stress, it was found that while the photosynthetic pigments and proline contents decreased in pepino leaves, the ascorbic acid, total phenolic compounds and malondialdehyde contents increased. In plants which were subjected to pre-treatment of ascorbic acid on the 10th day of stress, ascorbic acid and proline contents increased while a decrease was observed in malondialdehyde content, compared to stress group without pre-treated. This study may be important for explaining resistance induced by treatment of exogenous ascorbic acid in pepino exposed to chilling stress
Detection and genotype analysis of Giardia duodenalis from asymptomatic Hungarian inhabitants and comparative findings in three distinct locations
No full textThe transmission route of giardiasis not yet understood and why some infected individuals remain asymptomatic while others become quite ill. The drinking water quality is supposedly responsible for the prevalence of asymptomatic Giardia duodenalis infections in different areas, therefore asymptomatic giardiasis has been investigated in three water supply areas of Hungary: three hundred stool samples from inhabitants of Budapest, Füzér and Mátrafüred were examined by immunological and molecular methods for the presence of G. duodenalis infections. Individuals were asked to fill out a validated questionnaire at the time of stool collection and the interview covered demographic data, family life, education and travel history.In Budapest and in Mátrafüred in one stool sample G. duodenalis Assemblage A, whereas in Füzér once G. duodenalis Assemblage A, once Assemblage B and twice mixed infection were detected. We found higher prevalence rate of 4% of G. duodenalis infections of asymptomatic people in the village Füzér, where the removal of the Giardia cysts of the drinking water treatment plant was not effective. This study throws a light the need to look into the possibility of other risks of Giardia infections such as water transmission routes. To our knowledge, this is the first study evaluating the prevalence of G. duodenalis infections in asymptomatic persons in Hungary
Chitinase but N-acetyl-β-D-glucosaminidase production correlates to the biomass decline in Penicillium and Aspergillus species
No full textHydrolytic enzyme production is typical of the autolysis in filamentous fungi; however, less attention has been given to the physiological role of the enzymes. Here, the aim was to investigate the possible relation of the chitinolytic enzymes to the changes in the biomass in some filamentous fungi of high importance for pharmaceutical or food industry. In Penicillium and Aspergillus filamentous fungi, which showed different characteristics in submerged cultures, the growth and biomass decline rates were calculated and correlated to the chitinase and N-acetyl-β-D-glucosaminidase enzyme productions. Correlation was found between the biomass decrease rate and the chitinase level at the stationary growth phase; while chitinase production covariates negatively with N-acetyl-β-D-glucosaminidase activities. The chitinase production and the intensive autolysis hindered the production of N-acetyl-β-D-glucosaminidase and, therefore, could hinder the cell death in the cultures
A revised taxonomy for the subfamily Caloplacoideae (Teloschistaceae, Ascomycota) based on molecular phylogeny
No full textSeven strongly supported clades, characterised by molecular, morphological and anatomical characters are described as new genera: Eilifdahlia, Elenkiniana, Franwilsia, Huneckia, Marchantiana, Mikhtomia and Yoshimuria. Two new species, Eilifdahlia wirthii from South Africa and Marchantiana maulensis from Chile are described, illustrated and compared with closely related taxa
Kashiwadia gen. nov. (Physciaceae, lichen-forming Ascomycota), proved by phylogenetic analysis of the Eastern Asian Physciaceae
No full textThe new genus Kashiwadia S. Y. Kondr., L. Lőkös et J.-S. Hur, gen. nov. for the Eastern Asian species Physcia orientalis Kashiw. being in isolated position in the genus Physcia after morphological and anatomical characters as well as showing closer relation to the Heterodermia branch (than to the Physcia branch) in phylogenetic tree of the Physciaceae based on results of ITS1/ITS2 nuclear ribosomal and positioning in separate branch after 12S SSU mitochondrial DNA sequences and combined data set is proposed. Description of new genus and new combination is provided
Review article: Complexity of late blight resistance in potato and its potential in cultivar improvement
No full textLate blight disease caused by Phytophthora infestans is one of the most destructive diseases of potato. In the host an arsenal of genes may contribute to the resistance against the pathogen. In the presently available cultivars besides the so called field resistance which is conditioned by an unknown number of minor genes, race specific resistance genes were introgressed. Recently, broad spectrum resistance genes were identified, isolated and incorporated in breeding programs. The inbreeding depression that is characteristic for potato and the different sexual crossability problems associated with the potential resistance gene sources further complicate the development of cultivars with durable late blight resistance. The task to produce genotypes with resistance is challenged also by the recent occurrence of rapidly changing genotypes of the pathogen which are able to reproduce also sexually nowadays worldwide. Due to its importance, the genetic background of late blight resistance is intensively studied. The growing number of isolated major resistance genes and other genes involved in resistance response, as well as the identified QTLs allow the development of molecular tools which may be effectively used in breeding. In this review the complex status of resistance in potato to P. infestans and the breeding aspects of it is discussed