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The paper describes the use of liposomes and erythrocytes membrane as a real membrane models to evaluate the potential benefits of several plants extracts and two flavones in relation to lipid peroxidation. The antioxidant behaviour of the plant extracts from pine (Pinus silvestris L), hawthorn (Crataegus oxyacantha L, two extracts: from hawthorn’s leaves-l and bark-b), evening primrose (Oenothena paradoxa Hudziok – three extracts differ in procyanidins content P1, P2 and P3) and rosemary (Rosmarinus officinalis, as a standard for extracts) and flavones of baicalin and rutin have been studied. The results obtained showed that the studied extracts exhibited differentiated, dose-dependent antioxidant activity against phospatidylcholine liposomes (rosemary>pine≈hawthorn-l>hawthorn-b≈P1≈P2≈P3; statistically significant differences were observed between the extracts at p≤0.05) and erythrocyte membranes (rosemary≥hawthorn-b≈hawthorn-l>P1≈pine>P2≈P3) when the oxidation was induced by UV-C radiation. They also reduce the oxidation of liposomes and erythrocyte membrane when its oxidation was induced by 2,2’-azobis(2-amidinopropane) dihydrochloride (pine≥P1≈P2≈rosemary≈P3 in the case of liposomes and rosemary>> pine≥P1≈P2≥P3 in a case of erythrocyte). Moreover, the results of the study show that baicalin is characterised by high inhibition ability towards liposome PC peroxidation, as well as towards erythrocyte ghosts, when oxidation was initiated by UV radiation. However, at the same experimental conditions, the inhibitory capacity of rutin was about 7-8 times weaker. The presence of cholesterol in liposome membrane decreased the level of membrane peroxidation but do not influenced on the antioxidant activity of hawthorn extract.
In purpose to examine the antioxidant activity of 15 natural honeys of different origin ABTS method was used, total phenol content and dry matter content of honey samples were determined. Honeys were collected from different locations of Slovakia, Poland and Serbia and were represented as monofl oral and multifl oral samples (10) which originated from Poland and Slovakia, forest samples (4) originated from Serbia and honeydew honey. Average values of antioxidant activity observed in samples of honeys ranged from 0.62 to 4.63 mmol/kg. The highest antioxidant activity was detected in buckwheat honey and the lowest was shown in acacia honey. By observing the impact of individual honey samples on antioxidant activity it was found that the sample had a highly statistically signifi cant effect. 10 homogeneous groups which varied in the antioxidant activity among each other were established by all 15 samples. Antioxidant activity of honeys could be a positive infl uence factor in terms of honey differentiation, especially in the case of the forest honeys collected from different places. Monofl oral and multifl oral honeys (10) established 5 homogenous groups, but in the case of several multifl oral honeys which originated from different places of Poland and Slovakia no statistically signifi cant differences were found.
Amifostine is one of the cytoprotective drugs used during anticancer therapy. Amifostine as a thiol compound possesses antioxidant properties and protects only healthy cells against damage, mainly by scavenging reactivity oxygen species, competing with oxygen to prevent oxygen radical interactions with DNA, and promoting cell repair through hydrogen donation to reactive oxygen species. The aim of the present study was to evaluate antioxidative ability of amifostine in blood serum of rats exposed to cyclophosphamide during two weeks after drug administration. We show that amifostine only to a small degree prevents disorganisation of antioxidant systems of blood serum of rats caused by cyclophosphamide action. It is probably connected with low concentrations of amifostine active metabolites in the serum.
Z kory korzeni oraz sproszkowanego preparatu (EA) pochodzących z Uncaria tomentosa uzyskano wyciągi bogate w związki fenolowe. Wykazano silną aktywność przeciwwolnorodnikową tych wyciągów. Najsilniejszą aktywność przeciwwolnorodnikową wykazano dla wyciągu WMP otrzymanego z EA (MeOH - woda, 1:1). Wyciąg ten w stężeniach 0.036 i 0.072 mg/ml spowodował zmniejszenie stężenia wolnego rodnika DPPH odpowiednio o 64.6% i 92.8%.
Many compounds in mushrooms are biologically active; however, the in vivo actions of their metabolites are poorly understood. An in vitro system, GIS1, was used to simulate the fermentation action of microbiota in each colon region. We used MycoPo, a natural product obtained from the lyophilized mycelia of different Pleurotus ostreatus species to determine the biological effects in human-colon regions. Controls (Lentinula edodes mycelia; dried basidia of Agaricus brunnescens) were chosen to confi rm the biological activity of P. ostreatus mycelia in vitro. We measured total antioxidant capacity and ferric ion-reducing antioxidant power (FRAP) in simulated colon regions to identify antioxidant compounds, and undertook in vitro gastrointestinal simulation and microbiological analyses. The highest FRAP was found for the ascending colon, and the antioxidant effect was higher when MycoPo was administered. A. brunnescens consumption resulted in low total antioxidant capacity. Polyphenol content was correlated with the antioxidant status and microbial composition of microbiota. Total polyphenolic content was higher after A. brunnescens consumption, and four types of polyphenols were identifi ed by high-performance liquid chromatography. Major phenolic acids were gentisic acid, homogentisic acid, and small amounts of caffeic acid. The Enterobacteriaceae species populations varied greatly across the three parts of the colon. We noted a signifi cant (p<0.01) correlation between antioxidant status in the transverse and descending colon after MycoPo administration, and A. brunnescens consumption with the number of Lactobacillus and Bifi dobacteria species (R2 >0.85). These data suggest a direct relationship between favorable bacterial strains and availability of bioactive compounds, with specifi city for each colon region.
Studies were carried out to elucidate the anti-oxidative effect(s) of putrescine (10 mg/kg b.w./day) in rats treated per os with either sodium nitrite (10 mg/kg b.w./day) or normal saline (control) for 14 days. The putrescine was given to rats for 7 days only (days 7-14) and it was introduced 3-4 hrs after nitrite or saline dosage. Sodium nitrite increased thiobarbituric acid reactive substances (TBARS) in rat small intestinal mucosa and liver, and the agent did not have any effect on the total anti-oxidant status (TAS) and lipid peroxidation of rat blood. Nitrite did not also change the activity of superoxide dismutase (SOD) in the small intestinal mucosa, liver and blood, as well. Pretreatment of nitrite-treated rats with putrescine decreased TBARS and increased TAS in animals. Putrescine decreased SOD activity in the blood and liver of nitrite- and/or saline-treated rats, however, the agent did not affect the SOD enzyme in the small intestinal mucosa. Results suggest that putrescine dosed to nitrite-treated rats possesses some anti-oxidative properties.
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Flavonoids - food sources and health benefits

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Flavonoids are a group of bioactive compounds that are extensively found in foodstuffs of plant origin. Their regular consumption is associated with reduced risk of a number of chronic diseases, including cancer, cardiovascular disease (CVD) and neurodegenerative disorders. Flavonoids are classified into subgroups based on their chemical structure: flavanones, flavones, flavonols, flavan-3-ols, anthocyanins and isoflavones. Their actions at the molecular level include antioxidant effects, as well the ability to modulate several key enzymatic pathways. The growing body of scientific evidence indicates that flavonoids play a beneficial role in disease prevention, however further clinical and epidemiological trials are greatly needed. Among dietary sources of flavonoids there are fruits, vegetables, nuts, seeds and spices. Consumption of these substances with diet appears to be safe. It seems that a diet rich in flavonoids is beneficial and its promotion is thus justifiable.
Vitamin E is one of the major membrane protectants against reactive oxygen species ( ROS) and lipid peroxidation (LPO). The study aimed at determining the optimum dose of vitamin E to reverse free radical-mediated oxidative damage on motility, viability and LPO of bulls’sperm. Fresh semen of five local crossbred bulls was suspended in 2.9% sodium citrate, divided into equal fractions and subjected to vitamin E treatment (0, 1, 2, 2.5 mM) in the presence or absence of oxidative stress inducer, i.e ferrous ascorbate (FeAA, containing 150 μM FeSO4 and 750 μM ascorbic acid). All sperm suspensions were incubated at 37°C for 2 h. Treatment with FeAA reduced sperm motility and viability, but increased the LPO. All doses of vitamin E increased sperm motility and viability,but reduced LPO. However, 2 mM vitamin E was most effective. In conclusion, vitamin E reduced the LPO caused by FeAA, and improved sperm motility and viability in vitro under induced oxidative stress.
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