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Superoxide anion is produced in human platelets predominantly by Nox2-dependent NADPH oxidases. In vitro experiments have shown that it might play a role in modulating platelet functions. The relationship between platelet superoxide production and aggregation remains poorly defined. Accordingly, we aimed to study superoxide production and aggregation in platelets from subjects with significant cardiovascular risk factors (hypertension, hypercholesterolemia, smoking and diabetes mellitus) and from control individuals. Moreover, we studied the effects of novel polyphenol-rich extracts of Aronia melanocarpa (chokeberry) berries on platelet function in vitro. Superoxide production was significantly increased in patients with cardiovascular risk profile when compared to controls, while platelet aggregation in response to either collagen or thrombin were borderline higher, and did not reach statistical significance. Interestingly, no relationship was observed between platelet aggregation ex vivo and platelet superoxide production in either of studied groups. No correlation was found between endothelial function (measured by FMD) and platelet aggregation ex vivo either. Polyphenol-rich extracts of A. melanocarpa berries caused a significant concentration dependent decrease in superoxide production only in patients with cardiovascular risk factors, while no effect was observed in the control group. A. melanocarpa extracts abolished the difference in superoxide production between risk factor patients and controls. A. melanocarpa extracts exerted significant concentration dependent anti-aggregatory effects in both studied groups, which indicated that these effects may be independent of it’s ability to modulate superoxide production. The anti-aggregatory effects of chokeberry extracts were similar irrespective of aggregation inducing agent (collagen or thrombin). Moreover, they appear to be independent of platelet NO release as NOS inhibition by L-NAME did not lead to their abrogation. Platelet superoxide production is increased in subjects with cardiovascular risk factor profile, which may precede changes in platelet aggregation itself. Novel polyphenol rich extracts of A. melanocarpa berries exert significant anti-platelet effects ex vivo.
The aim of the study was to estimate nutritional and physiological consequences of combined supplementation of rat casein diets with a strongly oxidized mixture of fats and extract of polyphenols from chokeberry. The experiment was conducted on 80 young Wistar rats divided into 8 groups. The animals were fed diets supplemented with 8% of fresh or oxidized fats and 0.4, 0.8 and 1.2% of polyphenol extract together. Addition of the oxidized fats caused significant reduction in animal growth without a decrease in nitrogen digestibility. On the other hand, the extract of polyphenols suppressed nitrogen utilization; animal growth was however similar to the control group. Analysis of the variance showed negative influence of the oxidized fats on cholesterol and triacyloglycerol concentration in the blood of the experimental animals. Increased activity of both aminotransferases in the blood of rats fed diets containing the oxidized fats indicated on liver malfunction. There was no effect of the experimental factors on the antioxidant status of the blood, but a dose-dependent reduced content of malonylodialdehyde in the blood of rats fed diets supplemented with the extract of polyphenols suggested that the extract had a preventive effect against prooxidative activity of the oxidized fats.
The aim of the present research was to compare the communities of oribatid mites (Oribatida) on the plantations of chokeberry (Aronia melanocarpa (Michx.) Elliott) and blackcurrant (Ribes nigrum L.) as well as to define the effect of microirrigation on those Acari. The experiment was performed in degraded Phaeozems formed from sand, on shallow-deposited sand in Kruszyn Krajeński in the vicinity of Bydgoszcz. The soil reaction was slightly acid or acid and the differences in the acidity between chokeberry and blackcurrant were inconsiderable. The abundance of oribatid mites on chokeberry and blackcurrant plantations ranged from 3110 to 5290 individuals · m-2 and it was much higher, as compared with the neighbouring set-aside. The density of Oribatida on blackcurrant plantation was clearly higher than in chokeberry; however there was recorded no significant effect of the type of irrigation on the density. In total on both plantations there were reported 31 species of oribatid mites; mean species number s in blackcurrant was higher than in chokeberry. The dominance structure of oribatid mites on the chokeberry plantation was more even than in blackcurrant and in Tectocepheus velatus communities dominated mostly. The species preferred the blackcurrant plantation and irrigation stimulated its abundance. Chamobates schutzii, an oribatid mite, came second; it preferred the soil of chokeberry plantation; it was especially numerous on irrigated stands. Scutovertex sculptus also demonstrated some preference for chokeberry soil and no tolerance to irrigation. Whereas such oribatid mite species as Gymnodamaeus bicostatus, Metabelba pulverulenta, Oppiella nova, Quadroppia quadricarinata and Damaeus sp. showed some preference for the blackcurrant plantation.
The aim of the study was to determine the protective action of extracts from apple, strawberry and chokeberry with respect to linoleic acid and the biological membrane exposed to oxidation induced by physicochemical factors. The activity of the extracts was determined by measuring inhibition of lipid oxidation in red blood cell membrane, induced with UVC radiation and the AAPH radical. The protective effect of the extracts was essayed fl uorimetrically and spectrophotometrically. These results together with the ones obtained earlier explain the mechanism of the interaction between the extracts and the red blood cell membrane. The mechanism consists in the incorporation into the membrane and screening the cell against oxidation. The results indicate that the extracts possess very good antioxidant properties, since at the highest concentrations used (0.1 mg/mL) they protect the biological membranes almost entirely against oxidation. Among the extracts studied the best antioxidant properties were exhibited by the apple fruit, which gave 80% or 100% protection of the membrane at 0.05 mg/mL concentration of dry matter, for UVC and AAPH inductors, respectively.
The aim of the study was to compare the polyphenolic composition of extracts from different plant sources. Extracts from two new plants rich in polyphenols, i.e. chokeberries and honeysuckle, were compared with the well-investigated green tea polyphenols. All extracts obtained were characterised by a high content of polyphenols: green tea – 611 mg/g, honeysuckle – 633 mg/g and chokeberries – 714 mg/g. Honeysuckle and chokeberries extracts consisted mainly of anthocyanins (321.2 and 404.5 mg/g, respectively), whereas green tea extract contained mainly flavan-3-ols (587.9 mg/ g).
The antioxidant properties of extract from berries of Aronia melanocarpa (chokeberry) containing: anthocyanidines, phenolic acids and quercetine glycosides on oxidative/nitrative stress induced by peroxynitrite (ONOO-, a powerful physiological oxidant, nitrating species and inflammatory mediator) in human blood platelets were studied in vitro. The extract from A. melanocarpa (5 – 50 µg/mL) significantly inhibited platelet protein carbonylation (measured by ELISA method) and thiol oxidation estimated with 5,5’-dithio-bis(2-nitro-benzoic acid) (DTNB) induced by peroxynitrite (0.1 mM) (IC50 - 35 µg/mL for protein carbonylation, and IC50 - 33 µg/mL for protein thiol oxidation). The tested extract only slightly reduced platelet protein nitration (measured by C- ELISA method). The extract also caused a distinct reduction of platelet lipid peroxidation induced by peroxynitrite. Moreover, in our preliminary experiments we observed that the extract (50 µg/mL) reduced oxidative/nitrative stress in blood platelets from patients with breast cancer. The obtained results indicate that in vitro the extract from A. melanocarpa has the protective effects against peroxynitrite – induced oxidative/nitrative damage to the human platelet proteins and lipids. The extract from A. melanocarpa seems to be also useful as an antioxidant in patients with breast cancer.
W pracy przedstawiono możliwość użycia wytłoków zamiast suszonych owoców aronii w otrzymywaniu naparów. Oceniono wpływ sposobu suszenia wytłoków i owoców aronii na zawartość antocyjanów oraz barwę uzyskanych wyciągów wodnych. W porównaniu z tradycyjnym suszeniem owiewowym owoców zastosowane inne metody suszenia (mikrofalowe, próżniowe i liofilizacyjne) oraz użycie wytłoków znacznie poprawiło jakość naparów z suszu. Ze względu na wysoką temperaturę suszenia owiewowego i długi czas trwania procesu, barwa wyciągu przygotowanego z owoców suszonych metodą owiewową była jasna, o odcieniu brunatnym. W wyciągach wodnych z suszonych owiewowo wytłoków aroniowych użytych zamiast owoców uzyskano 2-krotne zmniejszenie zawartości glukozy, fruktozy i sorbitolu, natomiast ponad 11,5-krotny wzrost ilości monomerów antocyjanów.
Przedstawiono sposób otrzymywania i stabilizacji barwników z wytłoków aroniowych. W tym celu w produkcji soku dodano do miazgi aroniowej korzeń z tarczycy bajkalskiej w ilości 20, 30 i 40 g-kg-1. Dodatek ten umożliwił uzyskanie barwnika o 1,3-1,5 krotnie wyższej zawartości antocyjanów. Optymalna dawka korzenia tarczycy bajkalskiej dla miazgi aroniowej wyniosła 20 g kg-1. Flawony tarczycy bajkalskiej wpłynęły na poprawę barwy napojów podczas przechowywania.
Określono wpływ składu surowcowego liofilizowanych galaretek truskawkowych na ich wybrane właściwości fizyczne. Zakres pracy obejmował regulację właściwości suszonych sublimacyjnie galaretek przez dodatek glukozy i koncentratu z aronii. Analiza uzyskanych wyników posłużyła do podjęcia próby określenia optymalnej receptury do produkcji liofilizowanych galaretek truskawkowych. Liofilizowane galaretki truskawkowe otrzymano zgodnie z recepturą Wielobranżowego Przedsiębiorstwa Produkcyjno-Handlowego „Elena”. Do części próbek dodawano glukozę i koncentrat z aronii przed wprowadzeniem roztworu mleczanu wapnia. Dla otrzymanych liofilizowanych galaretek truskawkowych oznaczano aktywność i zawartość wody, barwę i właściwości rehydracyjne w temperaturze wody 20 i 80°C przez 10 minut. Wszystkie liofilizowane żele truskawkowe odznaczały się niską aktywnością wody i wysoką zawartością suchej substancji. Barwę żeli truskawkowych można regulować przez dodanie glukozy i koncentratu z aronii. Żele truskawkowe w większości cechują się bardzo dobrymi właściwościami rehydracyjnymi.
Materiał badawczy stanowiły owoce aronii, borówki czernicy i porzeczki czarnej o dojrzałości konsumpcyjnej. W owocach scharakteryzowano składniki dietetyczne - błonnik detergentowy kwaśny (ADF) i pektyny, składniki bioaktywne - związki fenolowe ogółem i antocyjany. Określono ponadto aktywność wiązania rodnika syntetycznego α,α-difenyl-ß-pikrylhydrazylowego (DPPH) i rodników hydroksylowych (OH) przez wyciągi metanolowe z owoców.
Epidemiological studies have indicated that fruits, vegetables and their products as juices consumption is associated with reduced risk of chronic diseases. Juices are besides fruits and vegetable suitable food products in term of ingestion of health protective phytochemicals.. They are good source of biological active compounds especially of polyphenols with anioxidants activity, free radical scavengers and metal chelators; they exhibit various physiological activities including anti-inflamatory, antiallergic, anticarcinogenic and antiarthritic activities. Berry fruit juices are one of the richest source of natural antioxidants, must be drinking in lager quantities, they are very important for the maintenance of health and prevention of disease. For increasing bioactive compounds in apple products it is necessary to improvement of clear apple juice processing and production or cloudy apple juice without clarification.
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