Wyniki wyszukiwania - Biblioteka Nauki

1

Disturbances of anti-oxidative balance in rats caused by aflatoxin B1

100%

Wojtowicz-Chomicz K. , Stadnik A. , Kowal M. , Sztanke K. , Sztanke M. , Borzecki A.

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2011

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tom 55

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nr 1

EN

The aim of the study was to analyse the effect of aflatoxin B₁ (AFB1) on total antioxidant status (TAS). The studies were conducted on Wistar male rats weighing 190-200 g. The animals were given for 7 d varied doses of AFB1, from 0.5 mg/kg b.w. to 2 mg/kg b.w. TAS and concentration of uric acid were determined in blood serum. The administration of AFB1 caused a decrease in TAS value, the most significant in the rats, which received the highest dose. AFB₁ disturbed the second line of defence against free radicals, which was proved by an increase in the second line defence antioxidant, i.e. uric acid.

2

Evaluation of selected parameters of the antioxidative system in patients with type 2 diabetes in different periods of metabolic compensation

100%

Rysz J. , Blaszczak R. , Banach M. , Kedziora-Kornatowska K. , Kornatowski T. , Tanski W. , Kedziora J.

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2007

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tom 55

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nr 5

3

The effect of dimethoate and pyrantel embonate intoxication on selected elements of antioxidative barrier in rats

100%

Wysocki A. , Zasadowski A.

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tom 13

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nr 2

4

Some physiological and biochemical aspects of plant resistance to cadmium effect. I. Antioxidative system

100%

Stroinski A.

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nr 2

EN

The hitherto studies on the effect of cadmium on plants have shown that it causes intensification of two types of unfavorable processes in plants: inactivation of macromolecules and cellular structures and induction of oxidative stress. In response, the plant organism activates processes restoring its homeostasis, i.e. those which remove reversible and irreversible changes. In removing the former a particular role is played by the antioxidative system containing enzymatic and nonenzymatic antioxidants, and removing the active forms of oxygen. The strategy of stress tolerance plays an important role in the plant resistance to cadmium and other toxic metals.

5

Effect of freezing dehydration on antioxidant system and cold tolerance in Norway spruce [Picea abies [L.] Karst.] seedlings

100%

Kaminska-Rozek E. , Pukacki P. M.

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tom 01

6

Phenolic compounds and properties of antioxidants in grapevine roots [Vitis vinifera L.] under low-temperature stress followed by recovery

84%

Weidner S. , Kordala E. , Brosowska-Arendt W. , Karamac M. , Kosinska A. , Amarowicz R.

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tom 78

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nr 4

279-286

EN

The research has been performed on roots of Vitis vinifera, cv. Himrod, obtained from seedlings grown under chill stress conditions (+10oC in the day and +7oC at night), under optimum conditions (+25oC in the day and +18oC at night) and from seedling which underwent a recover period after the chill stress treatment. The purpose of the study has been to determine quantitative and qualitative changes in phenolic compounds as well as to demonstrate changes in antiradical properties of extracts from grapevine roots, which appeared as a result of chill stress and during recovery under the optimum conditions following the stress. Phenolic compounds from grapevine roots were extracted using 80% acetone. The total content of phenolics was determined by colorimetry. The content of tannins was tested by precipitation with bovine serum albumin. The reducing power as well as DPPH• free radical and ABTS+• cation radical scavenging activity of the extracts were also tested. In order to identify phenolic compounds present in the extracts the RP-HPLC technique was employed. The tested material was found to contain tannins and three identified phenolic acids: ferulic, caffeic and p-coumaric ones. The latter occurred in the highest concentrations (from 4.46 to 6.28 µg/g fresh matter). Ferulic acid appeared in smaller amounts (from 1.68 to 2.65 µg/g fresh matter), followed by caffeic acid (from 0.87 to 1.55 µg/g fresh matter). Significantly less total phenolic compounds occurred in roots of seedlings subjected to chill stress. However, the total content of these compounds increased significantly in roots of plants which underwent recovery after chill stress. Concentration of tannins was determined by two methods. The content of condensed tannins was depressed in roots as a result of low temperature stress, whereas the content of condensed and hydrolysing tannins (determined via the BSA method) rose under chill stress conditions. A significant increase in tannins in root extracts (determined with both methods) was found during the recovery process after the stress. The three identified phenolic acids appeared in grapevine roots as ester-bound compounds. It has been demonstrated that the content of phenolic acids significantly fell as a result of low temperatures, but increased during recovery after chill stress. The weakest ability to scavenge DPPH• and ABTS+• free radicals as well as the reducing power were shown by the extract obtained from grapevine roots from the seedlings subjected to chill stress. Both free radical scavenging activity and reducing power were observed to increase considerably during recovery after stress. This seems to prove that during the recovery process following chill stress the synthesis of antioxidative compounds in grapevine roots is much more intensive.

7

Characteristics of the plant ascorbate peroxidase family

84%

Dabrowska G. , Kata A. , Goc A. , Szechynska-Hebda M. , Skrzypek E.

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nr 1

7-17

EN

This paper reviews plant ascorbate peroxidases (APX), an important part of the antioxidative system, maintaining the balance and uninterrupted functioning of the plant cell. The main role of APXs is to control the hydrogen peroxide concentration in cells. In reaction the enzymes use ascorbate as an electron donor. The active site is highly conserved by every member of the APX family. APXs belong to class I of the superfamily of bacterial, fungal and plant peroxidases. All the isoforms differ from each other in molecular weight, optimal pH, stability, substrate specificity, localization and level of response to specific stress conditions. It is suggested, however, that the responsible genes originated from one common gene by multiple duplication events followed by natural selection.

8

The influence of temperature on catalase gene expression pattern during callus regeneration of Triticum aestivum and Vicia faba ssp. minor

84%

Dabrowska G. , Kata A. , Skrzypek E. , Szechynska-Hebda M.

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nr 1 Suppl.

9

Reaction of cells Desmodesmus armatus (Chod.) Hegew. on the Induction of carotynogenesis

84%

Cheban L. , Dorosh I. , Marchenko M.

International Letters of Natural Sciences

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2018

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tom 72

EN

Various studies of the components of the antioxidant protection system of microalgae D. armatus under the influence of osmotic stress and active forms of oxygen will allow to develop methods for controlling carotenogenesis in a given culture and to obtain carotenoid enriched feed for zooplankton. These studies made it possible to evaluate the activity of catalase, peroxidase enzymes in cells that are cultured under the induction of carotenogenesis by free radical oxidation promoters and osmotic stress on the background of physiological changes. It is established that under these conditions, there is an increase in volumes and aggregation of vegetative cells. At the same time, the amount of biomass remains at the level of the first day of inductors application. Against the background of a decrease in growth activity, a decrease in the number of metabolically active cells in cytochrome oxidase was observed. It is also shown that, when iron sulfate is introduced with hydrogen peroxide and sodium chloride against the background of enhanced carotenogenesis, antioxidant systems are activated by increasing the activity of catalase and peroxidase. Under such conditions, it is possible to achieve increased production of carotenoids in Desmodesmus armatus culture.

10

Measurement of total antioxidant capacity - a review

84%

Zielinski H. , Kozlowska H.

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nr 2

EN

This review deals with selected recently used analytical methods for determining the antioxidant activity of compounds being investigated as well as total antioxidant capacity of the biological samples.

11

Enzymatic antioxidant systems in helminth parasites: no doubt on their evasive role

84%

Bruschi F. , Lucchi N. W.

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nr 4

12

Nitric oxide influences the plant cell antioxidant system

84%

Arasimowicz M. , Floryszak-Wieczorek J. , Milczarek G.

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nr 2 Spec.Vol.

13

Antioxidative system in roots of plants stressed by lead ions

84%

Malecka A. , Piechalak A. , Tomaszewska B.

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nr 2 Spec.Vol.

14

Aerobic conditions and antioxidative system of Azolla caroliniana Willd. in the presence of Hg in water solution

84%

Bennicelli R. P. , Balakhnina T. I. , Szajnocha K. , Banach A.

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2005

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tom 19

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nr 1

15

Influence of breast feeding on vitamin E concentration in plasma of infants with infection

67%

Jawniak R. , Furmaga-Jablonska W.

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nr Suppl.2, Part 1

EN

Vitamin E together with selenium-dependent glutathione peroxidase and catalase form the main antioxidative system of human cells. Vitamin E is indispensable nourishment component, since it cannot be synthesized by human cells. Therefore appropriate diet is an important factor determining antioxidave abilities of the organism. The aim of the study was to estimate feeding type influence on vitamin E concentration in blood plasma of infants hosptalized in Infants' Department. Study group consisted of 42 children (18 girls and 24 boys) aged 1 - 12 months, hospitalized due to pneumonia, otitis media, urinary tract infection, diarrhoea or sepsis. Children were divided into three groups concerning the type of feeding: 1. children feed with modified milk-30 (71.43%), 2. children feed with mother's milk-7 (16.67%), 3. children feed in mixed way - 5 (11.9%). Vitamin E plasma concentration was estimated by fluorometric method modified by Hansen and Warnick. Results were given in μg/mL. Statistical analysis was performed using NIR post-hoc test. P<0.05 was considered as statistically significant. We found statistically higher vitamin E concentration in blood plasma of infants fed only with mother's milk (25.28±10.33, range: 11.4-40 μg/mL) compared to the children fed with modified milk (18.56±6.74, range: 7.6-30 μg/mL) and these fed in mixed way (16.15±5.14, range: 11.8-23.5 μg/mL). Vitamin E concentration was the highest in blood plasma of infants fed only with mother's milk, which showed beneficial influence of breast feeding on vitamin E plasma concentration in infants with infection.

16

Characteristics of antioxidant system in dog semen

67%

Strzezek R. , Koziorowska-Gilun M. , Kowalowka M. , Strzezek J.

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tom 12

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nr 1

EN

The aim of the study was to characterize the enzymatic and non-enzymatic components comprising the antioxidant system in spermatozoa and individual fractions of dog ejaculate. Ejaculates were collected from six dogs of mixed-breeds. Total protein content, activity of antioxidant enzymes and the content of low-molecular antioxidants, such as L-glutathione (GSH), L-ergothioneine (ERG), L-ascorbic acid and total SH-group, were analyzed in the ejaculated spermatozoa and seminal plasma of the pre-spermatic, spermatic and post-spermatic fractions. The total antioxidant status (TAS) and antiperoxidant activity of the seminal plasma were also determined. The enzymatic antioxidant system of canine spermatozoa is mainly represented by superoxide dismutase (SOD) activity and, to a lesser extent, by glutathione peroxidase (GPx) and phospholipid hydroperoxide glutathione peroxidase (PHGPx) activity. Catalase activity was not detected either in the spermatozoa or in the different ejaculate fractions. GSH and ERG were detected in each fraction. Furthermore, a high level of L-ascorbic acid was observed in fractions of the ejaculate. Proteins and low-molecular weight antioxidants could influence the total antioxidant status and antiperoxidant activity of the seminal plasma. Increased suppressive activity against lipid peroxidation was shown only in the pre-spermatic and post-spermatic fractions. The different fractions of dog ejaculate, which are the main source of enzymatic antioxidants and low-molecular antioxidants, play an important role in protecting spermatozoa against reactive oxygen species.

17

Phenolic compounds and properties of antioxidants in grapevine roots [Vitis vinifera L.] under drought stress followed by recovery

67%

Weidner S. , Karolak M. , Karamac M. , Kosinska A. , Amarowicz R.

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tom 78

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nr 2

97-103

EN

Grapevine seedlings Vitis vinifera were grown in a greenhouse under optimum conditions (soil moisture ca 70%) and under drought stress (soil moisture ca 35%). In addition, some of the plants subjected to drought underwent subsequent regeneration under optimum conditions. Drought stress caused accumulation of total phenolic compounds in grapevine roots, which may indicate that these compounds play an important role in the adaptation of roots to growth under stress conditions. Phenolic acids found in the roots occurred in the ester-bound form only. p-coumaric acid was present in the highest concentrations (6.2 to 10.5 µg/g fresh matter). The content of ferulic acid was lower, ranging from 2.4 to 4.6 µg/g fresh matter. The lowest concentration in grapevine roots was achieved by caffeic acid (2.4 to 2.9 µg/g fresh matter). The levels of p-coumaric and ferulic acids in roots rose significantly under the drought stress, while the concentration of caffeic acid increased during the post-drought recovery period. This may suggest that some of the phenolic acids protect plants under stress conditions. All the extracts from grapevine roots had antioxidative properties, but the antiradical activity of the extracts obtained from roots subjected to drought stress was inferior to the control. The same extracts were also characterised by depressed reducing power. The results imply that tolerance of grapevine to soil drought may be associated with the value of antioxidative potential in root tissues of these plants.

18

Response of antioxidant systems to short-term NaCl stress in grapevine Rootstock-1616c and Vitis vinifera L. cv. Razaki

67%

Yildirim O. , Aras S. , Ergul A.

Acta Biologica Cracoviensia. Series Botanica

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2004

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tom 46

151-158

EN

The present study examined free-radical scavenging enzyme activity and the levels of lipid peroxide, ascorbic acid, nitric oxide and glutathione in 1616C rootstock and the Razaki cultivar of Vitis vinifera L. under treatment with different concentrations of salt. At day 7, in leaves of both 1616C rootstock and cv. Razaki treated with 12 mM NaCl there were significant increases in glutathione peroxidase and catalase activity, and in the levels of thiobarbituric acid reactive substance and reduced glutathione, measured on a protein basis and fresh weight basis. Superoxide dismutase activity increased under NaCl treatment at day 7 in both samples versus the controls. In the Razaki cultivar, glutathione peroxidase activity was at maximum at day 7 under 12 mM NaCl treatment. Catalase activity was very low, and increased with increasing NaCl concentration in the Razaki cultivar and 1616C rootstock at day 7. In 1616C rootstock the nitrite level was lower than the controls within 4 days.

19

Effect of osmotic stress and post-stress recovery on the content of phenolics and properties of antioxidants in germinating seeds of grapevine Vitis californica

67%

Weidner S. , Brosowska-Arendt W. , Szczechura W. , Karamac M. , Kosinska A. , Amarowicz R.

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nr 1

EN

The tested material consisted of grapevine Vitis californica stratified seeds germinated under optimum conditions (+25°C in water), under osmotic stress (-0.2 MPa in PEG solution) and submitted to recovery after stress (+25°C in water). The germinating seeds were determined to contain tannins, catechins and the following phenolic acids: gallic, caffeic, p-coumaric and ferulic. The acids occurred in free, ester- and glycoside-bound forms. The dominant form of phenolic acids was the ester-bound fraction. Gallic acid was the most abundant phenolic acid in germinating seeds, while ferulic acid appeared in the smallest amounts. Our analysis of tannins demonstrated that osmotic stress depressed their concentration. Presence of catechin group compounds such as catechin and epicatechin was also determined. In each sample epicatechin was dominant. The total concentration of catechin increased under stress conditions and declined during post-stress recovery. Catechins are a constituent of tannins and their increase under osmotic stress is most probably caused by the breakdown of some tannins in seeds germinating under stress conditions. Samples submitted to osmotic stress were also found to contain less of total phenolic compounds, whereas in samples which underwent post-stress recovery the total level of phenolic compounds increased. Compared to extracts from seeds germinating under optimum conditions, osmotic stress depressed the capacity of extract to scavenge DPPH● (2,2-diphenyl-1-picrylhydrazyl) and ABTS●+ – 2,2-Azino-bis (3-etylbenzothiazoline-6- -sulfonic acid) free radicals, but the antioxidant activity rose in seeds submitted to recovery after stress. Positive correlation was therefore demonstrated between the total content of phenolic acids in germinating grapevine seeds and the reducing power of extracts obtained from these seeds and their free radical scavenging activity. The results suggest that osmotic stress inhibits the activity of antioxidizing enzymes in germinating grapevine seeds. Thus, the antioxidative defence system is largely blocked under osmotic stress. It seems that a very high oxidoreductive potential in grapevine tissues prior to occurrence of osmotic stress is essential for maintaining proper homeostasis of oxidation and reduction reactions.

20

Drought and excess UV-B irradiation differentially alter the antioxidant system in cucumber leaves

67%

Kubis J. , Rybus-Zajac M.

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nr 2

35-41

EN

The combined effects of enhanced UV-B radiation and soil drought on antioxidant enzyme activity were investigated in cucumber leaves. One-month-old cucumber plants (Cucumis sativus cv. Dar) were exposed to UV-B irradiation and water deficit alone or combined. Physiological measurements were made in seedlings kept under stress conditions for nine days and then two more days with stresses withdrawn. Generally a decrease in relative water content and an increase in dry weight content were recorded. The more significant changes were observed under drought than under UV-B radiation and or combined UV-B and drought. Both stresses stimulated antioxidant enzyme activity. Superoxide dismutase activity increased earlier (day 2) than guaiacol peroxidase and glutathione reductase activity (days 5 and 7). Elevation of enzyme activities was higher under drought than under UV-B. Combined UV-B and drought functioned synergistically: one of the stresses reduced the effects caused by simultaneous application of the other.