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1.
In this study, we examined the modulation of Cu toxicity-induced oxidative stress by excess supply of iron in Zea mays L. plants. Plants receiving excess of Cu (100 μM) showed decreased water potential and simultaneously showed wilting in the
leaves. Later, the young leaves exhibited chlorosis and necrotic scorching of lamina. Excess of Cu suppressed growth, decreased
concentration of chloroplastic pigments and fresh and dry weight of plants. The activities of peroxidase (EC 1.11.1.7; POD),
ascorbate peroxidase (EC 1.11.1.11; APX) and superoxide dismutase (EC 1.15.1.1; SOD) were increased in plants supplied excess
of Cu. However, activity of catalase (EC 1.11.1.6; CAT), was depressed in these plants. In gel activities of isoforms of POD,
APX and SOD also revealed upregulation of these enzymes. Excess (500 μM)-Fe-supplemented Cu-stressed plants, however, looked
better in their phenotypic appearance, had increased concentration of chloroplastic pigments, dry weight, and improved leaf
tissue water status in comparison to the plants supplied excess of Cu. Moreover, activities of antioxidant enzymes including
CAT were further enhanced and thiobarbituric acid reactive substance (TBARS) and H2O2 concentrations decreased in excess-Fe-supplemented Cu-stressed plants. In situ accumulation of H2O2, contrary to that of O2
·− radical, increased in both leaf and roots of excess-Cu-stressed plants, but Cu-excess plants supplied with excess-Fe showed
reduced accumulation H2O2 and little higher of O2
·− in comparison to excess-Cu plants. It is, therefore, concluded that excess-Cu (100 μM) induces oxidative stress by increasing
production of H2O2 despite of increased antioxidant protection and that the excess-Cu-induced oxidative damage is minimized by excess supply
of Fe. 相似文献
2.
Harminder Pal Singh Daizy R. Batish Ravinder Kumar Kohli Komal Arora 《Plant Growth Regulation》2007,53(1):65-73
Arsenic (As) toxicity and its biochemical effects have been mostly evaluated in ferns and a few higher plants. In this study,
we investigated the effect of As (10.0 and 50.0 μM) on seedling growth, root anatomy, lipid peroxidation (malondialdehyde
and conjugated dienes), electrolyte leakage, H2O2 content, root oxidizability and the activities of antioxidant enzymes in mung bean (Phaseolus aureus Roxb.). Arsenic significantly enhanced lipid peroxidation (by 52% at 50.0 μM As), electrolyte leakage and oxidizability in
roots. However, there was no significant change in H2O2 content. Arsenic toxicity was associated with an increase in the activities of superoxide dismutase (SOD), guaiacol peroxidase
(GPX) and glutathione reductase (GR). In response to 50.0 μM As, the activities of SOD and GR increased by over 60% and 90%,
respectively. At 10.0 μM As, the activity of ascorbate peroxidase (APX) increased by 83%, whereas at 50.0 μM it declined significantly.
The catalase (CAT) activity, on the other hand, decreased in response to As exposure, and it corresponded to the observed
decrease in H2O2 content. We conclude that As causes a reduction in root elongation by inducing an oxidative stress that is related to enhanced
lipid peroxidation, but not to H2O2 accumulation. 相似文献
3.
Antioxidative responses were investigated in leaves of wheat (Triticum aestivum L.) grown at varying S levels ranging from deficiency to excess (1, 2, 4, 6 and 8 mM S). Optimum yield was observed in plants supplied with 4 mM S. Wheat responded to S deficiency and excess supply by decreasing growth of root and shoot. Chlorosis in young leaves was observed after 15 days of deficient S supply. The biomass and concentration of photoassimilatory pigments decreased in plants grown at 1, 2, 6 and 8 mM S supply. The concentration of thiobarbituric acid reactive substances (TBARS), cysteine, nonprotein thiol and hydrogen peroxide (H2O2) increased in plants grown under S stress. Accumulation of TBARS and H2O2 in leaves indicated oxidative damage in S-deficient and S-excess plants. Deficient and excess levels of S showed an increase in the activities of antioxidative enzymes superoxide dismutase (EC 1.15.1.1), catalase (EC 1.11.1.6), peroxidase (EC 1.11.1.7), ascorbate peroxidase (EC 1.11.1.11) and glutathione reductase (EC 1.6.4.2). 相似文献
4.
Q. H. Yuan G. X. Shi J. Zhao H. Zhang Q. S. Xu 《Russian Journal of Plant Physiology》2009,56(4):495-502
In this study, physiological, biochemical, and proteomic changes of Alternanthera philoxeroides leaves under zinc stress were investigated. Zinc is an essential micronutrient for plants, but it can be toxic at higher
concentrations. Accumulations of zinc and MDA in leaves increased significantly with the increase of zinc concentrations.
Zn considerably changed the activities of superoxide dismutase (SOD), catalase (CAT), and ascorbate peroxidase (APX). Zn also
altered the antioxidant level, such as reduced glutathione (GSH) and ascorbic acid (AsA). Therefore, it seems that zinc induced
oxidative stress in the leaves of A. philoxeroides, in which we found enhancement of antioxidant enzyme activities and antioxidant concentrations. Protein profiles analyzed
by two-dimensional electrophoresis revealed that five protein spots were up-regulated in zinc-treated samples. These differentially
displayed proteins were identified by mass spectrometry. The up-regulation of some antioxidant enzymes and stress-related
proteins clearly indicated that excess zinc generates oxidative stress that might be disruptive to other important metabolic
processes. These results indicate a good correlation between the physiological and biochemical changes in A. philoxeroides leaves exposed to excess zinc.
Published in Russian in Fiziologiya Rastenii, 2009, Vol. 56, No. 4, pp. 546–554.
This text was submitted by the authors in English. 相似文献
5.
Alicja Piotrowska Andrzej Bajguz Romuald Czerpak Katarzyna Kot 《Journal of Plant Growth Regulation》2010,29(1):53-62
The present study was undertaken to test the influence of exogenously applied jasmonic acid (JA) at concentrations of 0.01–100 μM
upon the growth and metabolism of the aquatic plant Wolffia
arrhiza (Lemnaceae). JA acted in a concentration-dependent manner. JA at 0.1 μM stimulated plant growth and accumulation of cellular
components (proteins, monosaccharides, chlorophylls, phaeophytins, and carotenoids). Treatment with JA at 0.1 μM enhanced
W.
arrhiza viability by the induction of biomass production and increased the level of photosynthetic pigments, monosaccharides, and
soluble proteins. Moreover, JA at 0.1 μM activated the enzymatic (catalase, ascorbate peroxidase, NADH peroxidase) and nonenzymatic
antioxidant (ascorbate, glutathione) system in W.
arrhiza and, therefore, suppressed lipid peroxidation. In contrast, decreases in fresh weight, major photosynthetic pigments, monosaccharides,
and soluble protein content were observed in W. arrhiza exposed to 100 μM JA. JA applied at 100 μM also stimulated the formation of lipid peroxides which are responsible for membrane
damage. In the presence of 100 μM JA, antioxidant enzyme (catalase, ascorbate peroxidase, NADH peroxidase) activity and ascorbate
as well as glutathione content were inhibited. The data support the hypothesis that JA plays an important role in W.
arrhiza growth and metabolism, regulating oxidative status by direct influence on the enzymatic as well as nonenzymatic antioxidant
machinery. 相似文献
6.
Nicéia Spanholi Calgaroto Denise Cargnelutti Liana Veronica Rossato Júlia Gomes Farias Sibila Trojahn Nunes Luciane Almeri Tabaldi Fabiane Goldschmidt Antes Erico Marlon Moraes Flores Maria Rosa Chitolina Schetinger Fernando Teixeira Nicoloso 《Biometals》2011,24(5):959-971
The possible role of zinc (Zn) to reverse the oxidative stress caused by mercury (Hg) was investigated in Pfaffia
glomerata plantlets. Thirty-day-old acclimatized plantlets of P. glomerata were exposed to four treatments: control, 50 μM Zn, 50 μM Hg and 50 μM Zn + 50 μM Hg for 9 days. In Zn + Hg treatment, shoot
and root Hg concentrations were 59 and 24% smaller than that plants exposed to 50 μM Hg added alone. An increase in the Zn
concentration in the shoot of plants exposed to Zn + Hg occurred, although in the roots Zn concentration was not altered,
when compared to the control. Fresh and dry weights, as well as the activity of δ-aminolevulinic acid dehydratase (δ-ALA-D)
in Hg-treated plants were significantly reduced. Percentage survival, fresh and dry weights and δ-ALA-D activity of plants
treated by 50 μM Zn + 50 μM Hg were greater than of that treated by Hg alone. Moreover, Zn treatment reduced the lipid peroxidation
caused by Hg, being this effect related to increased root superoxide dismutase activity, and shoot catalase and ascorbate
peroxidase activities. In conclusion, the presence of Zn in the substrate caused a significant reduction in the oxidative
stress induced by Hg. 相似文献
7.
M. Mukhopadhyay A. Das P. Subba P. Bantawa B. Sarkar P. Ghosh T. K. Mondal 《Biologia Plantarum》2013,57(3):474-480
Zinc is the most widespread deficient micronutrient in the tea growing soils of India which affects growth of the plants. In order to investigate the structural, physiological, and biochemical changes under Zn stress (i.e. both deficient and excess supply) of tea [Camellia sinensis (L.) O. Kuntze cv. T-78] plants, we treated young plants with ZnSO4 at 0 (deficiency), 0.3, 3 (optimum), and 30 μM (toxic) concentrations for 8 weeks. Zn deficiency and excess resulted in considerable decrease in shoot and root fresh and dry masses, and transmission electron microscopy (TEM) revealed disorganization of some cellular organelles. Further, Zn-stress decreased net photosynthetic rate (PN), transpiration rate (E), stomatal conductance (gs), and content of chlorophylls a and b. On the other hand, content of superoxide anion, malondialdehyde, hydrogen peroxide, and phenols, and electrolyte leakage were elevated in stressed plants. The activities of ascorbate peroxidase, catalase, superoxide dismutase, and peroxidase as well as expression of respective genes were up-regulated under Zn-stress. Nevertheless, antioxidant system as a whole did not afford sufficient protection against oxidative damage. 相似文献
8.
Antioxidant responses and water status in Brassica seedlings subjected to boron stress 总被引:1,自引:0,他引:1
The effect of boron (B) on growth, water status and oxidative damage was investigated in the leaves and roots of 7-day-old seedlings of Brassica juncea var. Varuna. For this seedlings of Brassica were grown in solution culture with variable boron supply (0.033, 0.33, 3.3 and 33 mg B L?1) under controlled conditions in green house. Photosynthetic pigments were found to be decreased more under excess (3.3 and 33 mg B L–1) than deficient boron supply (0.033 mg B L–1) when compared to control (0.33 mg B L–1). Accumulation of hydrogen peroxide and thiobarbituric acid reactive substances content in both leaves and roots under deficient and excess boron supply suggested oxidative damage due to excessive production of reactive oxygen species. Increased activity of antioxidative enzymes: superoxide dismutase, catalase and peroxidase along with polyphenol oxidase was observed in leaves and roots under boron deficiency and excess than in control. Increased proline concentration, decreased total water content and water saturation deficit also indicated the water deficit condition in leaves and roots of boron-stressed Brassica seedlings. 相似文献
9.
We studied the effects of different concentrations of mercury (0.0 to 100 μM) on growth and photosynthetic efficiency in rice
plants treated for 21 d. In addition, we investigated how this metal affected the malondialdehyde (MDA) content as well as
the activity of five antioxidant enzymes — superoxide dismutase (SOD), ascorbate peroxidase (APX), glutathione reductase (GR),
guaiacol peroxidase (POD), and catalase (CAT). Photosynthetic efficiency (Fμ/Fm) and seedling growth decreased as the concentration of Hg was increased in the growth media. Plants also responded to Hg-induced
oxidative stress by changing the levels of their antioxidative enzymes. Enhanced lipid peroxidation was observed in both leaves
and roots that had been exposed to oxidative stress, with leaves showing higher enzymatic activity. Both SOD and APX activities
increased in treatments with up to 50 μM Hg, then decreased at higher concentrations. In the leaves, both CAT and POD activities
increased gradually, with CAT levels decreasing at higher concentrations. In the roots, however, CAT activity remained unchanged
while that of POD increased a bit more than did the control for concentrations of up to 10 μM Hg. At higher Hg levels, both
CAT and POD activities decreased. GR activity increased in leaves exposed to no more than 0.25 μM Hg, then decreased gradually.
In contrast, its activity was greatly inhibited in the roots. Based on these results, we suggest that when rice plants are
exposed to different concentrations of mercury, their antioxidative enzymes become involved in defense mechanisms against
the free radicals that are induced by this stress. 相似文献
10.
Xuexia Wu Weimin Zhu Hui Zhang Haidong Ding Hong Juan Zhang 《Acta Physiologiae Plantarum》2011,33(4):1199-1209
Nitric oxide (NO) has emerged as a key molecule involved in many physiological events in plants. To characterize roles of
NO in tolerance of tomato (Lycopersicom esculentum Mill.) to salt stress, the protective effects of NO against salt-induced oxidative stress in the leaves of tomato cultivar
Hufan1480 (salt-tolerant) and Hufan2496 (salt-sensitive) were evaluated. Under salt stress, Hufan1480 showed higher biomass
accumulation, and less oxidative damage when compared with the Hufan2496. Application of exogenous sodium nitroprusside, a
NO donor, dramatically alleviated growth suppression induced by salt stress in two tomato ecotypes, reflected by decreased
malondialdehyde and O2·− production. Furthermore, the antioxidant enzymes superoxide dismutase, guaiacol peroxidase, catalase and ascorbate peroxidase,
the antioxidant metabolites ascorbate and reduced glutathione, and the osmosis molecules proline and soluble sugar were increased
in both ecotypes in the presence of NO under salt stress. Therefore, the protective effect of NO against salt-induced oxidative
damages in tomato seedlings is most likely mediated through stimulation of antioxidant system. 相似文献
11.
Copper-induced changes in the growth, oxidative metabolism, and saponin production in suspension culture roots of Panax ginseng in bioreactors 总被引:3,自引:0,他引:3
Roots of Panax ginseng exposed to various concentrations of Cu (0.0, 5, 10.0, 25.0, and 50.0 μM) accumulated high amounts of Cu in a concentration-dependent and duration-dependent manner. Roots treated with 50 μM Cu resulted in 52% and 89% growth inhibition after 20 and 40 days, respectively. Saponin synthesis was stimulated at a Cu concentration between 5 and 25 μM but decreased at 50 μM Cu. Malondialdehyde content (MDA), lipoxygenase activity (LOX), superoxide ion (O2
•−) accumulation, and H2O2 content at 5 and 10 μM Cu-treated roots were not increased but strongly increased at 50 μM Cu resulting in the oxidation of ascorbate (ASC) and glutathione (GSH) to dehydroascorbate (DHA) and glutathione disulfide (GSSG), respectively indicating a clear oxidative stress. Seven well-resolved bands of superoxide dismutase (SOD) were detected in the gel and an increase in SOD activity seemed to be mainly due to the induction of Fe-SOD 3. Five to 10 μM Cu slightly induced activity of ascorbate peroxidase (APX) and dehydroascorbate reductase (DHAR), guaiacol peroxidase (G-POD) but inhibited monodehydroascorbate reductase (MDHAR) and glutathione reductase (GR) enzyme activities. No changes in catalase (CAT) activity and in activity gel were found up to 25 μM Cu, but both G-POD and CAT activities were inhibited at 50 μM Cu. Glutathione metabolism enzymes such as γ-glutamylcysteine synthetase (γ-GCS), glutathione-S-transferase (GST), and glutathione peroxidase activities (GPx) were activated at 5 and 10 μM Cu but were strongly inhibited at 50 μM Cu due to the Cu accumulation in root tissues. The strong depletion of GSH at 50 μM Cu was associated to the strong induction of γ-glutamyltranspeptidase (γ-GGT) activity. These results indicate that plant could grow under Cu stress (5–25 μM) by modulating the antioxidant defense mechanism for combating Cu induced oxidative stress. 相似文献
12.
This paper mainly studies the possible antioxidant of monoterpene and effects of its absence on other antioxidant defense.
The leaves of rubber tree (Hevea brasiliensis) were fed with fosmidomycin through transpiration stream, in the dark, at room temperature for 2 h, and were then exposed
to bright illumination (1,500 μmol m−2 s−1) and moderately high temperature (30°C) for 1 h. The results showed that monoterpene biosynthesis in leaves was considerably
inhibited by fosmidomycin, and the elevated levels of both hydrogen peroxide and malondialdehyde were observed in the leaves
fed with fosmidomycin (LFF). Compared to the control leaves (CK), ∆F/F
m′ in the LFF was markedly lower during the first 20 min; however, there were no significant differences in non-photochemical
quenching and photosynthetic pigments (chlorophylls and carotenoids). In contrast, the activities of antioxidant enzymes (superoxide
dismutase, catalase, guaiacol peroxidase, ascorbate peroxidase, and glutathione reductase) were enhanced in the LFF. Meanwhile,
the contents of antioxidant metabolites (ascorbate and glutathione) were also elevated in the LFF, when compared with the
CK. The results obtained here suggest that monoterpene may be very effective molecule in protecting plants against oxidative
stress, the absence of monoterpene leads to the increased responses of the enzymatic and non-enzymatic antioxidant defenses
to oxidative stress, and the enhancement of the enzymatic and non-enzymatic antioxidant defenses may, in part, compensate
for the loss of antioxidant conferred by monoterpene. 相似文献
13.
Cadmium-induced oxidative damage and antioxidative defense mechanisms in <Emphasis Type="Italic">Vigna mungo</Emphasis> L. 总被引:1,自引:1,他引:0
Alicia S. Molina Carlos Nievas María Verónica Pérez Chaca Francisco Garibotto Ulises González Silvana M. Marsá Celina Luna María Sofía Giménez Fanny Zirulnik 《Plant Growth Regulation》2008,56(3):285-295
Cadmium (Cd)-induced oxidative stress and antioxidant defense mechanisms were analyzed in roots and leaves of Vigna mungo L. Seeds were germinated in perlite-vermiculite and irrigated with Hoagland nutrient solution. At day 6, seedlings were exposed
to 40 μM Cd under semi-hydroponic conditions for a period of 12 days. Growth anomalies and abnormal chromatin condensation
were observed in Cd-treated plants, in comparison with control ones. Cd accumulation was observed in roots of treated plants.
The analyses of antioxidative defense and oxidative parameters in roots, stems and leaves showed different tissue-specific
responses. Superoxide dismutase (SOD) and guaiacol peroxidase (GPx) activities and the level of lipid peroxidation (MDA content)
decreased in roots. However, they increased in leaves. Catalase activity and chlorophyll content, on the other hand, decreased
over exposure to Cd stress. Total glutathione, non-protein thiols, reduced glutathione (GSH) and phytochelatins increased
significantly, while oxidized glutathione (GSSG) decreased, as compared with control plants. The present data suggest that
the presence of Cd in soil and water can cause oxidative damage that may be detrimental for optimum production of nutritional
mung. 相似文献
14.
Antioxidant responses to enhanced generation of superoxide anion radical and hydrogen peroxide in the copper-stressed mulberry plants 总被引:14,自引:1,他引:13
The aim of the study was to implicate the generation of reactive oxygen species (ROS) and altered cellular redox environment with the effects of Cu-deficiency or Cu-excess in mulberry (Morus alba L.) cv. Kanva 2 plants. A study of antioxidative responses, indicators of oxidative damage and cellular redox environment in Cu-deficient or Cu-excess mulberry plants was undertaken. While the young leaves of plants supplied with nil Cu showed chlorosis and necrotic scorching of laminae, the older and middle leaves of plants supplied with nil or 0.1 μM Cu showed purplish-brown pigmented interveinal areas that later turned necrotic along the apices and margins of leaves. The Cu-excess plants showed accelerated senescence of the older leaves. The Cu-deficient plants showed accumulation of hydrogen peroxide and superoxide anion radical. The accumulation of hydrogen peroxide was strikingly intense in the middle portion of trichomes on Cu-deficient leaves. Though the concentration of total ascorbate increased with the increasing supply of Cu, the ratio of the redox couple (DHA/ascorbic acid) increased in Cu-deficient or Cu-excess plants. The activities of superoxide dismutase (EC 1.15.1.1), catalase (EC 1.11.1.6), peroxidase (EC 1.11.1.7), ascorbate peroxidase (EC 1.11.1.11) and glutathione reductase (EC 1.6.4.2) increased in both Cu-deficient and Cu-excess plants. The results suggest that deficiency of Cu aggravates oxidative stress through enhanced generation of ROS and disturbed redox couple. Excess of Cu damaged roots, accelerated the rate of senescence in the older leaves, induced antioxidant responses and disturbed the cellular redox environment in the young leaves of mulberry plants. 相似文献
15.
The influence of phytohormones, salicylic acid (SA) and methyl jasmonate (MJ) on the antioxidant systems in Haematococcus
pluvialis was investigated. Both SA and MJ at 500 μM concentration reduced the growth of alga with salicylic acid, having more pronounced
effect. Carotenoid and chlorophyll contents were decreased by SA and increased by MJ. Salicylic acid (100 μM) increased astaxanthin
content to 6.8-fold under low light (30 μmol m−2 s−1), while MJ (10 μM) showed marginal increase in astaxanthin. Salicylic acid (500 μM) increased superoxide dismutase activity
to 4.5- and 3.3-fold and ascorbate peroxidase (APX) activity to 15.5- and 7.1-fold under low and high light, respectively.
Methyl jasmonate increased catalase activity (1.4-fold) under high light and APX activity (5.4-fold) under low light. Different
mechanism of oxidative stress induced antioxidant production may be the plausible reason for this varied response for salicylic
acid and methyl jasmonate. Higher concentrations of SA and MJ inhibited astaxanthin accumulation by different mechanisms either
by scavenging the free radicals or by increasing primary carotenoids production. At lower concentrations, these phytohormones
could be used for elicitation of secondary carotenoid production. 相似文献
16.
17.
The effects of arsenite treatment on generation of reactive oxygen species, induction of oxidative stress, response of antioxidative
system, and synthesis of phytochelatins were investigated in two indica rice (Oryza sativa L.) cvs. Malviya-36 and Pant-12 grown in sand cultures for a period of 5–20 days. Arsenite (As2O3; 25 and 50 μM) treatment resulted in increased formation of superoxide anion (O2.−), elevated levels of H2O2 and thiobarbituric acid reactive substances, showing enhanced lipid peroxidation. An enhanced level of ascorbate (AA) and
glutathione (GSH) was observed irrespective of the variation in the level of dehydroascorbate (DHA) and oxidized glutathione
(GSSG) which in turn influenced redox ratios AA/DHA and GSH/GSSG. With progressive arsenite treatment, synthesis of total
acid soluble thiols and phytochelatins (PC) increased in the seedlings. Among antioxidative enzymes, the activities of superoxide
dismutase (EC 1.15.1.1), catalase (EC 1.11.1.6), total ascorbate peroxidase (APX, EC 1.11.1.11), chloroplastic ascorbate peroxidase,
guaiacol peroxidase (EC 1.11.1.7), monodehydroascorbate reductase (EC 1.6.5.4), and glutathione reductase (EC 1.6.4.2) increased
in arsenite treated seedlings, while dehyroascorbate reductase (EC 1.8.5.1) activity declined initially during 5–10 days and
increased thereafter. Results suggest that arsenite treatment causes oxidative stress in rice seedlings, increases the levels
of many enzymatic and non-enzymatic antioxidants, and induces synthesis of thiols and PCs, which may serve as important components
in mitigating arsenite-induced oxidative damage. 相似文献
18.
Toxic effects of lead (>0.2 mM Pb) were measured in pigeon pea (Cajanus cajan Mill) cv. UPAS grown in sand culture as reduction in growth, yield, and quality of seeds. Leaves containing >38 μg g−1 Pb showed oxidative damage as decrease in chlorophyll content and induction of antioxidants such as carotenoids, proline,
and non-protein thiol contents with enhanced activities of SOD and peroxidase. At excess (>0.2 mM) Pb, accumulation of >1,000 μg
Pb g−1 root tissue was associated with increase in non-protein thiol content. It is concluded that inhibition in root-to-shoot translocation
of Pb and induction in the level of proline, chloroplast pigments, and non-protein thiols and activities of antioxidant enzymes
SOD and peroxidase at <0.2 mM Pb could have protected the pigeon pea plants from the deleterious effects of Pb. However, excess
Pb at >0.2 mM showed a decline in yield, boldness, and quality of seeds despite the expression of an additional band each
of Cu–Zn SOD and peroxidase isoform. The threshold of toxicity and toxicity values in pigeon pea leaves of plants exhibiting
10 and 33% yield depression at 27 days after metal supply were 27 and 56 μg Pb g−1, respectively. 相似文献
19.
The effects of zinc on growth, boron uptake, lipid peroxidation, membrane permeability (MP), lypoxygenase (LOX) activity,
proline and H2O2 accumulation, and the activities of major antioxidant enzymes (superoxide dismutase (SOD), catalase (CAT), and ascorbate
peroxidase (APX)) in bean plants were investigated under greenhouse conditions. Treatments consisted of control, 20 mg/kg
B, and 20 mg/kg B plus 20 mg/kg Zn. When the plants were grown with 20 mg/kg Zn, B toxicity was less severe. Zinc supplied
to soil counteracted the deleterious effects of B on root and shoot growth. Excess B significantly increased and Zn treatment
reduced B concentrations in shoot and root tissues. Applied Zn increased the Zn concentration in the roots and shoots. While
the concentrations of H2O2 and proline were increased by B toxicity, their concentrations were decreased by Zn supply. Boron toxicity increased the
MP, malondialdehyde content, and LOX activity in excised bean leaves. Applied Zn significantly ameliorated the membrane deterioration.
Compared with control plants, the activity of SOD was increased while that of CAT was decreased and APX remained unchanged
in B-stressed plants. However, application of Zn decreased the SOD and increased the CAT and APX activities under toxic B
conditions. It is concluded that Zn supply alleviates B toxicity by preventing oxidative membrane damage.
Published in Russian in Fiziologiya Rastenii, 2009, Vol. 56, No. 4, pp. 555–562.
This text was submitted by the authors in English. 相似文献
20.
Nzengue Y Steiman R Rachidi W Favier A Guiraud P 《Biological trace element research》2012,146(3):410-419
In this report, we have investigated the role of copper (Cu) and zinc (Zn) in oxidative stress induced by cadmium (Cd) in
C6 cells. Cells were exposed to 20 μM Cd, 500 μM Cu, and 450 μM Zn for 24 h. Then, toxic effects, cellular metals levels,
oxidative stress parameters, cell death, as well as DNA damage were evaluated. Cd induced an increase in cellular Cd, Cu,
and Zn levels. This results not only in the inhibition of GSH-Px, GRase, CAT, and SOD activities but also in ROS overproduction,
oxidative damage, and apoptotic cell death not related to Cu and Zn mechanisms. The thiol groups and GSH levels decreased,
whereas the lipid peroxidation and DNA damage increased. The toxicity of Zn results from the imbalance between the inhibition
of antioxidant activities and the induction of MT synthesis. The increase in Cu and Zn levels could be explained by the disruption
of specific transporter activities, Cd interference with signaling pathways, and metal displacement. Our results suggest that
the alteration of Cu and Zn homeostasis is involved in the oxidative stress induced by Cd. 相似文献