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Content available Substancje biologicznie aktywne w winie
EN
Wines are the subject of an increasing number of investigations. The benefits of red wine became widely recognized after the observation of “French paradox” [8–10]. It has been found that there is a low mortality rate from ischemic heart disease among French people despite their high consumption of saturated fatty acids and the prevalence of other risk factors. The health-protective properties of wine are attributed to their antioxidant activity, i.e. the capability to scavenge reactive oxygen species, ROS . An imbalance between antioxidants and oxygen species results in oxidative stress leading to cellular damage. The phenolic compounds present in wine show beneficial physiological properties including protection against coronary heart disease, as well as anti-inflammatory and anti-carcinogenic activity. Most of the beneficial effects of wine are attributed to the presence of flavonoids, resveratrol, phenolic acids and other antioxidants. This paper reviews the significance of different compounds present in wine and their effect on human health. Chapter 1 focuses on flavonoids: flavonols, flavan-3-ols and anthocyanidins (Fig. 1) [14–29]. This class of compounds can exist both in a simple form, as aglycones, and bounded with sugars, as glycosides. The presence of phenolic hydroxyl group in these compounds is essential for their antioxidant activity and enables to scavenge free radicals in vivo. Chapter 2 describes chemical and physicochemical properties of resveratrol (Fig. 2) [30-41] which is the main antioxidant in wine. Moreover, this compound has been shown to inhibit the oxidation of low density lipoproteins and the aggregation of platelets [44-47]. Resveratrol also exhibits anti-inflammatory and anticancer properties [48, 49]. Chapter 3 reveals that wines are also a good source of other antioxidants [50–55] as phenolic acids (Fig. 3), tyrosol and hydroxytyrosol (Fig. 4), and also melatonin (Fig. 5). Unfortunately, some wines can include mycotoxins, mainly ochratoxin A [59, 60] (Fig. 6), which is produced by the phytopatogenic fungi, Aspergillus carbonarius. All types of red wine contain different amounts of ethanol and phenolic antioxidants, and therefore it is probable that the cardioprotective effect of red wine is caused by both these kinds of components [57–58]. Epidemiological observations, clinical and experimental in vitro research prove that regular and moderate intake of wine, particularly red wine, reduces cardiovascular morbidity and mortality [66–70].
PL
Wolne rodniki odgrywają istotną rolę w funkcjonowaniu żywych organizmów. Biorą one udział w regulowaniu metabolizmu, oczyszczaniu, przekazywaniu sygnałów i wspomaganiu systemu odpornościowego. Mogą być także przyczyną wielu schorzeń, takich jak nowotwory, miażdżyca czy różnego rodzaju stany zapalne. Wolne rodniki powstają w wyniku procesów metabolicznych, ale również pod wpływem czynników zewnętrznych, np. pożarów. W artykule zostały omówione zewnętrzne źródła powstawania wolnych rodników i sposoby ochrony przed ich szkodliwym działaniem.
EN
The article describes the sources of reactive forms of oxygen and nitrogen, especially considering the external sources. The special attention has been paid to their influence on firefighters health who, because of their profession, are especially exposed to so called oxidative stress. Further, the author presents ways of fighting the reactive forms of oxygen and nitrogen using antioxidative compounds.
PL
Żele polimerowe można zdefiniować jako jedną makrocząsteczkę w postaci sieci polimerowej wypełnioną rozpuszczalnikiem. Zawartość wody w hydrożelach jest zazwyczaj wyższa niż 95%, niemniej jednak materiały te mają właściwości charakterystyczne dla cieczy i ciał stałych. Dzięki swojej specyficznej budowie i wrażliwości na czynniki środowiskowe żele znalazły wiele zastosowań w różnych dziedzinach. W poniższym artykule przedstawiono niektóre z tych zastosowań.
EN
Thanks to their properties the polymeric hydrogels are very useful in both, various industrial branches as well as in every day life. Many research teams aim at finding new hydrogels which will have bigger and other applications. They also aim at the synthesis of new hydrogels with strictly defined properties. Those materials should show big sorbing capacity comparing to water solutions and to specified chemical substances. Hydrogels, which undergo phase transition in specified environmental and which are sensitive to other and new environmental factors, have been searched.
PL
W artykule przedstawiono ogólną charakterystykę, podział oraz metody otrzymywania żeli ze szczególnym uwzględnieniem żeli podlegających zjawisku objętościowego przejścia fazowego. Następnie bardziej szczegółowo omówiono zjawisko objętościowego przejścia fazowego żeli. Wspomniano także o praktycznych możliwościach jego zastosowania.
EN
The article presents general characteristics and the methods of preparation of gels. Particular attention is given to the gels undergoing the volume phase transition. This transition is illustrated in detail. Possible applications are discussed too.
PL
W artykule przedstawiono koncepcję wykorzystania zmodyfikowanej farby ogniochronnej jako indykatora temperatury. Pokazano również wynik badań eksperymentalnych na modelach zestyków pokrytych powłokami wytworzonej mieszaniny.
EN
The article presents the test results of thermoindicator made on the base of fire resistant paint. The proposed thermoindicator has got many advantages proved by the test results.
EN
In the last decades, free radicals have been discussed to play a key role in the pathology of several diseases, such as cancer, artheriosclerosis or inflammatory diseases [1, 2]. Numerous dietary antioxidants, e.g. vitamin C, phenolic and polyphenolic compounds as well as carotenoides are considered as effective agents in prevention of these diseases [4]. The chemical diversity of antioxidants occurring in food makes it difficult to separate individual antioxidant compounds from the animal or vegetable matrix and quantify them. Antioxidant activity is widely used as a parameter to characterize the redox status of different biological or dietary samples. Many analytical methods for determining of total antioxidant activity (TAA) have been proposed in the literature of the last decade. The present review deals with the methods involving electron-transfer reactions with chromogen compounds: the trolox equivalent antioxidant capacity (TEAC) [6-29], the DPPH assay [31-41], the ferric reducing antioxidant power (FRAP) assay [42-48], the cupric reducing antioxidant capacity (CUPRAC) assay [49-55], and the Folin-Ciocalteu (FC) method [56]. These assays enable to measure the activity of an antioxidant through the reduction of an oxidizing agent, which changes colour during the redox reaction. The degree of colour change corresponds to the concentration of antioxidant in the sample. The main purpose of this review is to describe and discuss the chemical fundamentals of these methods. The applications of voltammetry and other electroanalytical methods were also demonstrated [58-71]. In addition, properties and the use of reference compounds in the antioxidant activity assessment was considered [72-85]. The summary contains conclusions on the scope of application, the most important advantages and shortcomings of the methods described [50, 86-88].
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