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1.
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
2.
J. F. Gonçalves L. A. Tabaldi D. Cargnelutti L. B. Pereira J. Maldaner A. G. Becker L. V. Rossato R. Rauber M. D. Bagatini D. A. Bisognin M. R. C. Schetinger F. T. Nicoloso 《Biometals》2009,22(5):779-792
A hydroponic experiment was carried out to characterize the oxidative stress responses of two potato cultivars (Solanum tuberosum L. cvs. Asterix and Macaca) to cadmium (Cd). Plantlets were exposed to four Cd levels (0, 50, 100, 150 and 200 μM) for 7 days.
Cd concentration was increased in both roots and shoot. Number of sprouts and roots was not decreased, whereas Cd treatment
affected the number of nodal segments. Chlorophyll content and ALA-D activity were decreased in both cultivars, whereas carotenoids
content was decreased only in Macaca. Cd caused lipid peroxidation in roots and shoot of both cultivars. Protein oxidation
was only verified at the highest Cd level. H2O2 content was increased in roots and shoot of Asterix, and apparently, a compensatory response between roots and shoot of Macaca
was observed. SOD activity was inhibited in roots of Asterix at all Cd treatments, whereas in Macaca it was only increased
at two highest Cd levels. Shoot SOD activity increased in Asterix and decreased in Macaca. Root CAT activity in Asterix decreased
at 100 and 150 μM, whereas in Macaca it decreased only at 50 μM. Shoot CAT activity was decreased in Macaca. Root AsA content
in Macaca was not affected, whereas in shoot it was reduced at 100 μM and increased at 200 μM. Cd caused increase in NPSH
content in roots and shoot. Our results suggest that Cd induces oxidative stress in both potato cultivars and that of the
two cultivars, Asterix showed greater sensitivity to Cd levels. 相似文献
3.
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
4.
Wei XJ Wu J Ni YD Lu LZ Zhao RQ 《In vitro cellular & developmental biology. Animal》2011,47(10):735-741
Previous studies have shown that the in ovo injection of equol can markedly improve the water-holding capacity of muscles
of broilers chickens at 7 wk of age through promotion of the antioxidant status. We aimed to investigate directly the antioxidant
effects of equol on muscle cells in broilers. Muscle cells were separated from leg muscle of embryos on the 11th day of incubation
and treated with equol and H2O2, either alone or together. Cells were pretreated with medium containing 1, 10, or 100 μM equol for 1 h prior to the addition
of 1 mM H2O2 for a further 1 h. Photomicrographs of cells were obtained. Cell viability, malondialdehyde (MDA) content, and L-lactate
dehydrogenase (LDH) activity in the cell supernatant, as well as intracellular total superoxide dismutase (T-SOD) and glutathione
peroxidase (GSH-Px) activities were determined. Treatment with 1 mM H2O2 caused serious damage to cells, indicated by comets with no clear head region but a very apparent tail of DNA fragments.
Pretreatment with low (1 μM) but not high concentrations of equol (10 μM) inhibited cell damage, while 100 μM equol caused
more serious damage than H2O2 alone. Pretreatment with 1 μM equol had no effect on cell viability, while pretreatment with 10 and 100 μM equol significantly
decreased cell viability in a dose-dependent manner. Compared with H2O2 alone, pretreatment with low-dosage equol markedly decreased LDH activity and MDA production in the supernatant, significantly
increased intracellular T-SOD activity (P < 0.05) and tended to increase intracellular GSH-Px activity (0.05 < P < 0.1). Pretreatment with high-dosage equol (10 and 100 μM) significantly enhanced LDH activity, but had no effect on MDA
content, T-SOD or GSH-Px activity induced by H2O2, except for an obvious increase in GSH-Px activity caused by 10 μM equol. These results indicate that equol at low dosage
can prevent skeletal muscle cell damage induced by H2O2, while pretreatment with high-dosage equol shows a synergistic effect with H2O2 in inducing cell damage. 相似文献
5.
6.
Shao-Hang Lin Zhong-Jing Liu Pei-Lei Xu Ye-Ying Fang Ji-Gang Bai 《Acta Physiologiae Plantarum》2011,33(2):295-304
To investigate whether paraquat (PQ) is involved in regulation of antioxidant enzymes and lipid peroxidation under short-term
salt stress, and to elucidate the physiological mechanism of salt stress mitigated by PQ, a cucumber cultivar (cv. Chunguang
no. 2) was exposed to 100 mM NaCl for 48 h after pre-treatment with 10 μM PQ for 1 h. When compared to the control, salt stress
increased the levels of malonaldehyde (MDA), superoxide radical (O2·−) and hydrogen peroxide (H2O2) and the activities of antioxidant enzymes, such as superoxide dismutase (EC 1.15.1.1), ascorbate peroxidase (EC 1.11.1.11)
and glutathione reductase (EC 1.6.4.2) in the cucumber leaves. Under salt conditions, PQ pre-treatment prevented oxidative
stress as observed by the decreases in MDA, H2O2 and O2·− that correlated with the increase in antioxidant defenses. We propose that, at low concentrations, the PQ pre-treatment can
reduce the salt-induced oxidative damage by increasing the antioxidative mechanisms in cucumber plants. 相似文献
7.
8.
We examined ameliorative effects of salicylic acid (SA) on two cadmium (Cd)-stressed legume crops with different Cd tolerances,
viz. Phaseolus aureus (Cd sensitive) and Vicia sativa (Cd tolerant). Cd at 50 μM significantly increased the production of hydrogen peroxide (H2O2) and superoxide anion (O2·−) in root apoplasts of P. aureus and V. sativa. When comparing the two species, we determined that Cd-induced production of H2O2 and O2·− was more pronounced in P. aureus root apoplasts than in V. sativa root apoplasts. V. sativa had higher activities of superoxide dismutase (SOD), catalase (CAT), and ascorbate peroxidase (APX) than P. aureus in root symplasts and apoplasts. Seed-soaking pretreatment with 100 μM SA decreased Cd-induced production of H2O2 and O2·− in apoplasts of both species, and increased activities of symplastic and apoplastic SOD, symplastic APX, and apoplastic CAT
under Cd stress. Hence, SA-induced Cd tolerances in P. aureus and V. sativa are likely associated with increases in symplastic and apoplastic antioxidant enzyme activities. 相似文献
9.
Cadmium-induced initial changes in the production of reactive oxygen species (ROS) and antioxidant mechanism were investigated
in soybean (Glycine max L. cv. Don Mario 4800 RR) leaves. Whole plants (WP) and plants without roots (PWR) were exposed to 0.0, 10.0 and 40.0 μM
Cd for 0, 4, 6 and 24 h. Compared to PWR, a higher level of endogenous Cd in WP was associated with a lower oxidative stress
measured in terms of lipid peroxidation. Furthermore, O2
•− content decreased in the leaves of Cd-treated WP, whereas it increased in those of Cd-treated PWR. Although O2
•− accumulation in PWR was associated with a decrease in superoxide dismutase (SOD) activity, O2
•− diminution in WP leaves was not related to any increase in SOD activity. H2O2 content increased in the leaves of both Cd-treated WP and PWR, and it was concomitant with a corresponding decline in catalase
(CAT) and ascorbate peroxidase (APX) activities. When diphenyl iodonium (DPI), an inhibitor of NADPH oxidase, was added, H2O2 content remained unchanged in Cd-treated WP, suggesting that NADPH oxidase does not participate in the early hours of Cd
toxicity. Taken together, our results showed that early ROS evolution and oxidative damage were different in WP and PWR. This
suggests that the response in soybean leaves during the early hours of Cd toxicity is probably modulated by the root. 相似文献
10.
Fei Chen Fang Wang Hongyan Sun Yue Cai Weihua Mao Guoping Zhang Eva Vincze Feibo Wu 《Journal of Plant Growth Regulation》2010,29(4):394-408
A greenhouse hydroponic experiment was performed using Cd-sensitive (cv. Dong 17) and Cd-tolerant (Weisuobuzhi) barley seedlings
to evaluate how different genotypes responded to cadmium (Cd) toxicity in the presence of sodium nitroprusside (SNP), a nitric
oxide (NO) donor. Results showed that 5 μM Cd increased the accumulation of O2•−, H2O2, and malondialdehyde (MDA) but reduced plant height, chlorophyll content, net photosynthetic rate (P
n), and biomass, with a much more severe response in the Cd-sensitive genotype. Antioxidant enzyme activities increased significantly
under Cd stress in the roots of the tolerant genotype, whereas in leaves of the sensitive genotype, superoxide dismutase (SOD)
and ascorbate peroxide (APX), especially cytosol ascorbate peroxidase (cAPX), decreased after 5–15 days Cd exposure. Moreover,
Cd induces NO synthesis by stimulating nitrate reductase and nitric oxide synthetase-like enzymes in roots/leaves. A Cd-induced
NO transient increase in roots of the Cd-tolerant genotype might partly contribute to its Cd tolerance. Exogenous NO dramatically
alleviated Cd toxicity, markedly diminished Cd-induced reactive oxygen species (ROS) and MDA accumulation, ameliorated Cd-induced
damage to leaf/root ultrastructure, and increased chlorophyll content and P
n. External NO counteracted the pattern of alterations in certain antioxidant enzymes induced by Cd; for example, it significantly
elevated the depressed SOD, APX, and catalase (CAT) activities in the Cd-sensitive genotype after 10- and 15-day treatments.
Furthermore, NO significantly increased stromal APX and Mn-SOD activities in both genotypes and upregulated Cd-induced decrease
in cAPX activity and gene expression of root/leaf cAPX and leaf CAT1 in the Cd-sensitive genotype. These data suggest that under Cd stress, NO, as a potent antioxidant, protects barley seedlings
against oxidative damage by directly and indirectly scavenging ROS and helps to maintain stability and integrity of the subcellular
structure. 相似文献
11.
12.
Glutamate induces oxidative stress and apoptosis in cerebral vascular endothelial cells: contributions of HO-1 and HO-2 to cytoprotection 总被引:4,自引:0,他引:4
Parfenova Helena; Basuroy Shyamali; Bhattacharya Sujoy; Tcheranova Dilyara; Qu Yan; Regan Raymond F.; Leffler Charles W. 《American journal of physiology. Cell physiology》2006,290(5):C1399
In cerebral circulation, epileptic seizures associated with excessive release of the excitatory neurotransmitter glutamate cause endothelial injury. Heme oxygenase (HO), which metabolizes heme to a vasodilator, carbon monoxide (CO), and antioxidants, biliverdin/bilirubin, is highly expressed in cerebral microvessels as a constitutive isoform, HO-2, whereas the inducible form, HO-1, is not detectable. Using cerebral vascular endothelial cells from newborn pigs and HO-2-knockout mice, we addressed the hypotheses that 1) glutamate induces oxidative stress-related endothelial death by apoptosis, and 2) HO-1 and HO-2 are protective against glutamate cytotoxicity. In cerebral endothelial cells, glutamate (0.12.0 mM) increased formation of reactive oxygen species, including superoxide radicals, and induced major keystone events of apoptosis, such as NF-B nuclear translocation, caspase-3 activation, DNA fragmentation, and cell detachment. Glutamate-induced apoptosis was greatly exacerbated in HO-2 gene-deleted murine cerebrovascular endothelial cells and in porcine cells with pharmacologically inhibited HO-2 activity. Glutamate toxicity was prevented by superoxide dismutase, suggesting apoptotic changes are oxidative stress related. When HO-1 was pharmacologically upregulated by cobalt protoporphyrin, apoptotic effects of glutamate in cerebral endothelial cells were completely prevented. Glutamate-induced reactive oxygen species production and apoptosis were blocked by a CO-releasing compound, CORM-A1 (50 µM), and by bilirubin (1 µM), consistent with the antioxidant and cytoprotective roles of the end products of HO activity. We conclude that both HO-1 and HO-2 have anti-apoptotic effects against oxidative stress-related glutamate toxicity in cerebral vascular endothelium. Although HO-1, when induced, provides powerful protection, HO-2 is an essential endogenous anti-apoptotic factor against glutamate toxicity in the cerebral vascular endothelium. endothelium; carbon monoxide; bilirubin; injury; reactive oxygen species; heme oxygenase 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.
Arredondo M Fuentes M Jorquera D Candia V Carrasco E Leiva E Mujica V Hertrampf E Pérez F 《Biological trace element research》2011,143(2):625-636
To assess the relationship between the length of (GT)
n
repeats in HO-1 gene promoter and heme oxygenase (HO) enzymatic activity in mononuclear cells with iron (Fe) stores in type
2 diabetic mellitus (DM2) patients and metabolic syndrome (MS) subjects, we studied 163 patients with DM2, 185 with MS, and
120 controls subjects. We evaluated iron status (hemoglobin and serum Fe, ferritin, and transferrin receptor), and we determined
the length of (GT)
n
repeats in HO-1 gene promoter by capillary electrophoresis and HO enzymatic activity in mononuclear cells and assessed the
relationship between these results and Fe stores. Only 1/163, 6/185, and 7/120 had iron deficiency anemia in DM2 patients,
MS subjects, and controls, respectively. No iron overload (ferritin >200 μg/L) was detected in all the subjects studied. DM2
patients had higher iron deposits, total body iron, and heme oxygenase activity (a suggestion of high oxidative stress condition)
than MS subjects and controls. In DM2, we found a positive association between serum iron and HO activity. There were no difference
in allelic frequency between the three groups; however, among DM2 and MS patients, the frequency of short/medium (SM) genotype
of (GT)
n
repetition was increased and medium/medium (MM) genotype of (GT)
n
repetition was lower than controls. These results imply that DM2 patients and individuals with MS carrying SM repeats might
have higher susceptibility to develop diabetes consequences. This increased susceptibility could be Fe-mediated oxidative
stress. 相似文献
15.
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
16.
17.
Glioblastoma patients receive anti-inflammatory agent for alleviation of vasogenic edema and pain prior to surgery, radiotherapy,
and chemotherapy. Oxidative stress is an important mechanism of action of some chemotherapeutic agents in the treatment of
glioblastoma. So, we examined the modulatory effects of methylprednisolone (MP, a steroidal anti-inflammatory agent) and indomethacin
(IM, a non-steroidal anti-inflammatory agent) on apoptosis in rat C6 glioblastoma cells following oxidative stress with hydrogen
peroxide (H2O2). Exposure of C6 cells to 1 mM H2O2 for 24 h caused significant amounts of morphological and biochemical features of apoptosis. Expressions of Bax and Bcl-2
at mRNA and protein levels were altered resulting in an increase in Bax : Bcl-2 ratio in apoptotic cells, which also exhibited
overexpression of 80 kDa calpain and an increase in calpain-cleaved 145 kDa α-spectrin breakdown product. Immunofluorescent
and propidium iodide labeling detected caspase-3-p20 fragment in apoptotic cells, indicating activation of caspase-3 as well.
Treatment of cells with 1 μM MP or 10 μM IM alone did not induce apoptosis. Pretreatment (1 h) with either 1 μM MP or 10 μM
IM significantly inhibited H2O2 mediated apoptosis in C6 cells. Thus, pretreatment of glioblastoma with an anti-inflammatory agent, either steroidal or non-steroidal,
may compromise the action of a chemotherapeutic agent that mediates therapeutic action via oxidative stress. 相似文献
18.
Oxidative stress can be a significant cause of cell death and apoptosis. We performed studies in HepG2 cells to explore whether
prior exposure to oxidative stress (“oxidative preconditioning”) and geldanamycin (GA) treatment can protect the cell from
damage caused by subsequent oxidative insults. The cells were treated with 10 nM GA for 24 h before oxidative stress. Oxidative
preconditioning was achieved by 2 h exposures to H2O2 (50 μM) separated by a 10-h recovery period in normal culture medium. Oxidative stress was induced by exposure to 500 μM
H2O2 for 24 h. The effects of GA and oxidative preconditioning were investigated on the formation of Hsp90, vimentin, insoluble
vimentin aggregates, and cleavage of vimentin in a cell culture model of oxidative stress. GA treatment leads to enhanced
expression of Hsp90 and vimentin and to inhibition of vimentin protein aggregation. Similar results were obtained by oxidative
preconditioning. It is confirmed that low concentrations of GA protected HepG2 cells from subsequent oxidative stress by increasing
the levels of Hsp90 and by alleviating the extent of cell apoptosis induced by oxidative stress, which is similar to oxidative
preconditioning. However, in contrast to preconditioning, GA treatment obviously changed binding activity of Hsp90 to vimentin
cleavages. All the above indicated that low concentrations of GA treatment triggered cell protection from oxidative stress.
Both the level of Hsp90 and its ability to bind with vimentin were changed by low concentrations of GA and might contribute
to oxidative stress protection. 相似文献
19.
The effects of cadmium (Cd) stress on lipid composition and biosynthesis were investigated in young leaves of ten-day-old
tomato seedlings (Lycopersicon esculentum Mill. cv. Ibiza F1). Cd was found to be mainly accumulated in roots, but a severe inhibition of biomass production occurred
in leaves, even at its low concentration (1.0 μM). Seven days after Cd treatment, the membrane lipids were extracted and separated
on silica-gel thin layer chromatography (TLC). Fatty acid methyl esters were analyzed by FID-GC on a capillary column. Our
results showed that Cd stress decreased the quantities of all lipids classes (phospholipids, galactolipids and neutral lipids).
Likewise, there was also a decline in the levels of tri-unsaturated fatty acids, such as linolenic (C18:3) and hexadecatrienoic
(C16:3) acids. The linolenic acid (C18:3) decreased in monogalactosyldiacylglycerol (MGDG) and all phospholipids, while hexadecatrienoinic
acid (C16:3) declined mainly in MGDG. Moreover, Cd at high concentrations (25.0 and 50.0 μM) significantly enhanced the levels
of lipid peroxides. Radiolabelling experiments were carried out by laying down microdroplets of [1-14C]acetate–a major precursor of lipid biosynthesis–on attached leaves of the control and Cd-treated plants. After incubation
for 1, 2, 12 and 24 h, the leaves were harvested and lipids extracted and analysed. Cd stress was found to decrease the incorporation
of [1-14C]acetate in total lipids. The biosynthesis of total lipids was altered with 25.0 and 50.0 μM Cd. The decline in the incorporation
of [1-14C]acetate due to Cd stress was observed in all lipid classes. There was also a substantial decline in the incorporation of
[1-14C]acetate in tri-unsaturated fatty acids. The results indicate that Cd treatment induces an oxidative stress by inhibiting
the chloroplastic and extrachloroplastic lipid-biosynthesis pathways as well as lipid peroxidation. 相似文献
20.
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