Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P30044 (antioxidant enzyme)
 8,037 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

We investigated the effects of short-term salinity stress and spermidine application to salinized nutrient solution on polyamine metabolism and various stress defense reactions in the roots of two cucumber (Cucumis sativus L.) cultivars, Changchun mici and Jinchun No. 2. Seedlings grown in nutrient solution salinized with 50mM NaCl for 8d displayed reduced relative water content, net photosynthetic rates and plant growth, together with increased lipid peroxidation and electrolyte leakage in the roots. These changes were more marked in cv. Jinchun No. 2 than in cv. Changchun mici, confirming that the latter cultivar is more salinity-tolerant than the former. Salinity stress caused an increase in superoxide and hydrogen peroxide production, particularly in cv. Jinchun No. 2 roots, while the salinity-induced increase in antioxidant enzyme activities and proline contents in the roots was much larger in cv. Changchun mici than in cv. Jinchun No. 2. In comparison to cv. Jinchun No. 2, cv. Changchun mici showed a marked increase in arginine decarboxylase, ornithine decarboxylase, S-adenosylmethionine decarboxylase and diamine oxidase activities, as well as free spermidine and spermine, soluble conjugated and insoluble bound putrescine, spermidine and spermine contents in the roots during exposure to salinity. On the other hand, spermidine application to salinized nutrient solution resulted in alleviation of the salinity-induced membrane damage in the roots and plant growth and photosynthesis inhibition, together with an increase in polyamine and proline contents and antioxidant enzyme activities in the roots of cv. Jinchun No. 2 but not of cv. Changchun mici. These results suggest that spermidine confers short-term salinity tolerance on cucumber probably through inducing antioxidant enzymes and osmoticants.
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PMID:Exogenous spermidine affects polyamine metabolism in salinity-stressed Cucumis sativus roots and enhances short-term salinity tolerance. 1824 70

Soil flooding constitutes a seasonal factor that negatively affects plant performance and crop yields. In this work, the relationship between oxidative damage and flooding sensitivity was addressed in three citrus genotypes with different abilities to tolerate waterlogging. We examined leaf visible damage, oxidative damage in terms of malondialdehyde (MDA) concentration, leaf proline concentration, leaf and root ascorbate and glutathione contents and the antioxidant enzyme activities superoxide dismutase (EC 1.15.1.1), ascorbate peroxidase (EC 1.11.1.11), catalase (EC 1.11.1.6) and glutathione reductase (EC 1.8.1.7). No differences in the extent of oxidative damage relative to controls were found among genotypes. However, a different ability to delay the apparition of oxidative damage was associated to a higher tolerance to waterlogging. This ability was linked to an enhanced activated oxygen species' scavenging capacity in terms of an increased antioxidant enzyme activity and higher content in polar antioxidant compounds. Therefore, the existence of a direct relationship between stress sensitivity and the early accumulation of MDA is proposed. In addition, data indicate that the protective role of proline has to be considered minimal as its accumulation was inversely correlated with tolerance to the stress. The positive antioxidant response in Carrizo citrange (Poncirus trifoliata L. Raf. x Citrus sinensis L. Osb.) and Citrumelo CPB 4475 (Poncirus trifoliata L. Raf. x Citrus paradisi L. Macf.) might be responsible for a higher tolerance to flooding stress, whereas in Cleopatra mandarin (Citrus reshni Hort. Ex Tan.), the early accumulation of MDA seems to be associated to an impaired ability for H2O2 scavenging.
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PMID:Antioxidant enzymatic activity is linked to waterlogging stress tolerance in citrus. 1833 99

In order to obtain salt-tolerant variant plants of Dandelion (Taraxacum officinale Weber), the leaf discs were excised from 20 to 30-day old seedlings to produce callus, then the induced calli were transferred to selection mediums containing 1.5% NaCl. After regenerating and rooting, these salt-tolerant calli finally developed into 12 variant plantlets. Compared with the wild-type, these regenerated plants produced more trichomes on their leaves, and had larger leaves and shorter petioles. Additionally, the dumpy roots and an approximately 2-cm bract in middle parts of the floricanes were clearly observed in these salt-tolerant plants. By RAPD (Random Amplified Polymorphic DNA) and SDS-PAGE analysis, these salt-tolerant plants showed differences from the control at DNA and protein levels. With 1.5% NaCl treatment, the antioxidant enzyme activity, proline content, and flavonoid concentration were higher in these salt-tolerant plants, whereas maloaldehyde concentration was significantly lower. Salt-tolerant lines of T. officinale showed stronger anti-oxidative activity and higher flavonoid contents.
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PMID:[Selection and identification of salt-tolerant variants of Taraxacum officinale]. 1846 11

Phytotoxicity of cadmium on growing Arachis hypogaea L. seedlings was studied. Seeds were exposed to 25, 50, and 100 micromol/L CdCl2 concentrations, for a period of 10, 15, 20 and 25 d. The extent of damage to chlorophyll, protein, proline, nitrate and nitrite reductase, antioxidant enzyme activity in leaves and roots were evaluated after 10 d of cadmium stress. The higher concentration of cadmium (100 micromol/L) resulted (leaves and roots) total chlorophyll 91.01%, protein 79.51%, 83.61%, nitrate reductase 79.39%, 80.72% and nitrite reductase 77.07%, 75.88% activity decreased with increase in cadmium concentrations and exposure periods. Cadmium caused significant changes in the activity of antioxidative enzymes. Contrastingly Cd treated plant tissues showed an increase in proline 159.87%, 239.6%, gluthion reductase (GR) 337.72%, 306.14%, superoxide disumutase (SOD) 688.56%, 381.72%, ascorbate peroxidase (APX) 226.47%, 252.14%, peroxidase (POD) 72.19%, 60.29% and catalase (CAT) 228.96%, 214.74% as compared to control. Cadmium stress caused a significant increase in the rate of SOD activity in leaves and roots of plant species. Results show the crop A. hypogaea is highly sensitive even at very low cadmium concentrations.
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PMID:Phytotoxicity of cadmium on protein, proline and antioxidant enzyme activities in growing Arachis hypogaea L. seedlings. 1857 62

The effect of drought on the chickpea variety ILC 3279 was investigated at the vegetative stage. After 20 days from sowing, the plants subjected to drought stress for 3, 5 and 7 days imposed by withholding water were permitted to recover by rewatering for 2 days after 3, 5 and 7 days of drought. Shoot elongation, leaf production, fresh and dry biomass reduced while MDA and proline accumulation increased with extended duration of stress. The plants stressed for 3 days exhibited a rapid drop in their relative and absolute water contents. The quantum efficiency of PSII open centres in the dark-adapted and light-saturated state, excitation energy trapping of PSII and electron transport rate decreased significantly from the 5th day to the end of the drought treatments. Plants drought-stressed for 7 days brought about a marked increase in non-photochemical energy dissipation and a marked decline in photochemical quenching. After rewatering all chlorophyll a fluorescence characteristics except for F(M) completely recovered and reached the control values. Under 5 and 7 days of drought, the anthocyanin content increased gradually while the total chlorophyll content of leaves declined compared to the controls. The total carotenoid content remained unchanged during the experiments. The antioxidant enzyme response to drought treatments was quite variable. The total SOD activity upregulated with increasing duration of stress. On the other hand, the total APX activity was significantly higher only on the 7th day while the total POD activity increased from the 5th day. Differences in the total GR activity of treated groups were not statistically significant compared to their controls throughout the treatments. The present results indicate that the chickpea variety ILC 3279 withstands severe drought with its upregulated protective mechanisms at the vegetative stage.
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PMID:PSII photochemistry and antioxidant responses of a chickpea variety exposed to drought. 1881 Oct 6

In order to study effects of different salinity levels on antioxidant enzyme activities, catalase (CAT), ascorbate peroxidase (APX) and guaiacol peroxidase (GPX) associated with compatible solutes, proline and carbohydrate and mineral nutrient content in shoots, sodium and potassium, in three wheat cultivars an experiment was conducted as completely randomized 3 x 4 factorial design with three replicates in a greenhouse. Three wheat cultivars (Pishtaz, Kavir and Hamon), that differ in their salt tolerances, were grown in four different salinity levels (S0 = control, S1 = 100, S2 = 200 and S3 = 300 mM NaCl). Twenty days after wheat cultivars subjected to salt stress, data showed salinity stress induced increase in the antioxidant enzyme activities. Among the cultivars, salinity stress decreased leaf-APX but increased the activities of leaf-GPX in Pishtaz cultivar. Our results showed a positive correlation between praline accumulation and Leaf-APX (r2 = 0.56), Leaf-GPX (r2 = 0.63) and Leaf-CAT (r2 = 0.73). In these cultivars, in their shoots Na+ showed an increase in concentration with salinity that approximately matches a decrease in K+ concentration. It seems that Na+ concentrations in the shoot may have had a more significant effect on plant antioxidant enzyme activities and compatible solutes such as proline and carbohydrates. These results indicated which in wheat under salinity stress antioxidant enzymes and compatible solutes help to plant adaptation. In this study we found a positive correlation between Na+ concentration in the shoots and the antioxidant enzyme activities and compatible solutes in the leaves.
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PMID:Salinity effects on compatible solutes, antioxidants enzymes and ion content in three wheat cultivars. 1881 74

Soil flooding is a seasonal factor that negatively affects plant performance and crop yields. In order to investigate the effects of spermidine (Spd) and spermine (Spm) on the waterlogging stress, it was checked that the content of relative water content (RWC), proline, chlorophyll and malondialdehyde (MDA), net photosynthesis, the rate of hydrogen peroxide (H(2)O(2)) and superoxide radicals (O(2)(-)) generation and the antioxidant enzyme activities of superoxide dismutase (SOD) (EC 1.15.1.1), catalase (CAT) (EC 1.11.1.6), ascorbate peroxidase (APX) (EC 1.11.1.11) and glutathione reductase (GR) (EC 1.6.4.2) in Welsh onion (Allium fistulosum L) plants. Pretreatment with 2 mM of Spd and Spm effectively maintained the balance of water content in plant leaves and roots under flooding stress. In addition, the data indicate that the protective role of proline should be considered minimal, as its accumulation was found to be inversely correlated with tolerance to stress; it also significantly retarded the loss of chlorophyll, enhanced photosynthesis, decreased the rate of O(2)(-) generation and H(2)O(2) content, and prevented flooding-induced lipid peroxidation. Spd and Spm helped to maintain antioxidant enzyme activities under flooding; however, APX activity was found to increase slightly in response to Spm. The antioxidant system, an important component of the water-stress-protective mechanism, can be changed by PAs, which are able to moderate the radical scavenging system and to lessen in this way the oxidative stress. The results suggest that pretreatment with Spd and Spm prevents oxidative damage, and the protective effect of Spd was found to be greater than that of Spm.
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PMID:Waterlogging tolerance of Welsh onion (Allium fistulosum L.) enhanced by exogenous spermidine and spermine. 1935 40

Populus cathayana Rehd., a dioecious tree species, occupies a wide range of habitats in southwest China. Both males and females were grown under two regimes of photoperiod, from mid-length to short-day photoperiod (SD shift), or to long-day photoperiod (LD shift). SD shift triggered leaf senescence in both males and females by decreasing net photosynthesis rate (A), transpiration (E), and chlorophyll pigment (Chl), non-structural carbohydrate (NSC) and indoleacetic acid (IAA) contents, while increasing abscisic acid (ABA), malonaldehyde (MDA) and free proline (Pro) contents. The antioxidant enzyme (e.g. POD, CAT and SOD) activities and capability to maintain ultrastructural integrity also decreased under SD shift. Males exhibited faster leaf senescence than did females, as shown by greater decreases in A, E, Chl and IAA. However, males maintained a less senescent stage than did females, as indicated by higher values of A, Chl, NSC, IAA and antioxidant enzyme activities. Conversely, A, E, NSC and IAA contents and antioxidant enzyme activities were enhanced by lower O(2)(*-) in females, whereas reduced by higher O(2)(*-) in males under LD shift. Such sex-dependent responses of P. cathayana to photoperiod transitions showed that males and females possess different adaptabilities, which may relate to sex-specific leaf senescence speed under changing environments.
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PMID:Sex-related adaptive responses of Populus cathayana to photoperiod transitions. 1955 65

Field studies were conducted from 2002 to 2005 to evaluate foliar spray of Atonik (a plant growth regulator (PGR) containing nitrophenolates) on cotton boll abscission rate by assessing various reactive oxygen species (ROS) contents, antioxidant content and antioxidant enzyme activity from 1 to 9 days after anthesis (DAA). The result indicated that the nitrophenolate spray reduced hydrogen peroxide (H(2)O(2)), superoxide anion (O(2)(-)) accumulation, lipid peroxidation (malondialdehyde--MDA), lipoxygenase (LOX) activity and membrane permeability relative to the control. Antioxidant enzyme activity (superoxide dismutase, SOD; ascorbate peroxidase, APX; peroxidase, POX; glutathione peroxidase, GSH-Px) was significantly increased by the nitrophenolate spray. The POX (217%) and GSH-Px (242%) activities were enhanced compared with APX (7.7%) activity at 9 DAA. Enhanced accumulation of ascorbate (245%), phenol (253%) and proline (150%) was observed in nitrophenolate-sprayed plants compared with control at 9 DAA. Because ascorbate content is increased by higher dehydroascorbate reductase (DHAR) enzyme activity, the ascorbate was able to replenish reducing equivalents to phenoxyl radicals, resulting in an increase of phenolic compounds. The increased phenolic acid content may be involved in scavenging the ROS produced in developing cotton boll. The role of DHAR and glutathione reductase (GR) in keeping higher levels of reduced ascorbate and low levels of endogenous H(2)O(2) in the developing cotton boll may be the prerequisite for boll retention. Based on the present work, we conclude that nitrophenolate-sprayed plants counteracted the deleterious effects of ROS by the peroxide/phenolics/ascorbate system, which causes reduced boll abscission and increased yield.
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PMID:Nitrophenolates spray can alter boll abscission rate in cotton through enhanced peroxidase activity and increased ascorbate and phenolics levels. 1964 35

The influence of the arbuscular mycorrhizal (AM) fungus, Glomus etunicatum, on characteristics of growth, membrane lipid peroxidation, osmotic adjustment, and activity of antioxidant enzymes in leaves and roots of maize (Zea mays L.) plants was studied in pot culture under temperature stress. The maize plants were placed in a sand and soil mixture under normal temperature for 6 weeks and then exposed to five different temperature treatments (5 degrees C, 15 degrees C, 25 degrees C, 35 degrees C, and 40 degrees C) for 1 week. AM symbiosis decreased membrane relative permeability and malondialdehyde content in leaves and roots. The contents of soluble sugar content and proline in roots were higher, but leaf proline content was lower in mycorrhizal than nonmycorrhizal plants. AM colonization increased the activities of superoxide dismutase, catalase, and peroxidase in leaves and roots. The results indicate that the AM fungus is capable of alleviating the damage caused by temperature stress on maize plants by reducing membrane lipid peroxidation and membrane permeability and increasing the accumulation of osmotic adjustment compounds and antioxidant enzyme activity. Consequently, arbuscular mycorrhiza formation highly enhanced the extreme temperature tolerance of maize plant, which increased host biomass and promoted plant growth.
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PMID:Influence of arbuscular mycorrhiza on lipid peroxidation and antioxidant enzyme activity of maize plants under temperature stress. 1993 1


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