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1.
The present piece of work highlights the comparative effects of two active forms of brassinosteroids (BRs), 28-homobrassinolide
(HBL) and 24-epibrassinolide (EBL), on growth parameters, carbonic anhydrase activity and photosynthetic parameters in Lycopersicon esculentum (cv. K-21) sampled at 45 (24 h after spray) and 60 days after sowing, under natural conditions. Out of the two active forms
of BR, EBL proved better than HBL in improving the above parameters, when applied as foliar spray. Of the three concentrations
(10−6 M, 10−8 M or 10−10 M) of HBL and EBL, 10−8M proved best in both cases. 相似文献
2.
Sikander Pal Choudhary Renu Bhardwaj B. D. Gupta Prabhu Dutt R. K. Gupta Mukesh Kanwar Stefania Biondi 《Acta Physiologiae Plantarum》2011,33(4):1319-1333
The present investigation recorded significant restoration of seedling growth (root length, shoot length and fresh weight)
upon application of 24-epibrassinolide (EBL) and putrescine (Put) to 7-day-old seedlings of Raphanus sativus L. cv. Pusa chetki grown under copper (Cu) ion stress. EBL and Put with/or without Cu ion treated seedlings showed increased
titers of ascorbic acid, total phenols and proline when compared with Cu-stressed seedlings. Differential responses in the
activities of guaiacol peroxidase (GPOX) and catalase (CAT) were noted for EBL and Put alone or with/or without Cu ion treatment.
Decreased activities of glutathione reductase (GR) and superoxide dismutase (SOD) noted for EBL and Put alone were observed
to enhance significantly when applied in combination with Cu ion solution. A remarkable decrease in malondialdehyde contents
was observed in seedlings treated with EBL and Put alone and with/or without Cu ion stress. Enhanced free radical scavenging
activities were also recorded for seedlings given EBL and Put alone or in combination over Cu ion stressed seedlings. Maximum
DPPH activity was observed in seedlings treated with Put and EBL 10−9 M + Put. Significant enhancements in deoxyribose and reducing power activities were too recorded for Put, EBL and Put + 10−9 M EBL treatments. Improved seedling growth, antioxidant levels (ascorbic acid, total phenols and proline) and enzymic (GPOX,
CAT, SOD and GR) activities and free radical scavenging capacities along with reduced membrane damage in seedlings given EBL
and Put with/or without Cu stress suggests significant and positive interactions of EBL and Put in alleviating the Cu ion
induced oxidative damage in radish seedlings. 相似文献
3.
Honghong Fan Tingchun Li Lei Guan Zhengpeng Li Ning Guo Yongping Cai Yi Lin 《Plant Cell, Tissue and Organ Culture》2012,109(2):307-314
Nitric oxide (NO) is an important biological messenger in plants, which has been implicated in response to abiotic stress.
To study the effects of exogenous NO on drought menace, the tube seedlings of Dendrobium huoshanense were selected and treated with 10% polyethylene glycol (PEG-6000) to simulate drought stress. After application of sodium
nitroprusside (SNP), the relative water content (RWC) and antioxidant enzyme activities were determined. As a result, plant
treated with 50 μmol L−1 of SNP maintained high level of RWC and lower content of malondialdehyde (MDA). Furthermore, the antioxidant enzyme activities
were obviously enhanced. However, the higher concentration of SNP (100 μmol L−1) enhanced the effects of drought stress for plant. For further analysis of the response mechanism to exogenous NO, the methylation-sensitive
amplified polymorphism (MSAP) technique was used to investigate the changes of DNA methylation. When the seedlings of Dendrobium huoshanense were treated with 50 μmol L−1 SNP containing 10% PEG-6000, levels of global DNA methylation of Dendrobium huoshanense were decreased. Nevertheless, the demethylation rate of methylated sites increased, accounting for 12.5% of total methylation
sites. These results implied that some expressed genes were involved in the response process to drought stress triggered by
NO in Dendrobium huoshanense. 相似文献
4.
Chun-Hua Wu Rajesh Kumar Tewari Eun-Joo Hahn Kee-Yoeup Paek 《Journal of Plant Biology》2007,50(6):636-643
Nitric oxide and reactive oxygen species are important signal molecules that play key roles in plant defense responses. We
investigated the involvement of nitric oxide elicitation in the synthesis of secondary metabolites within the adventitious
roots ofEchinacea purpurea. When roots were treated with 100 μM sodium nitroprusside (SNP), an exogenous nitric oxide producer, the accumulation of phenolics,
flavonoids, and caffeic acid derivatives was enhanced. This level of SNP also induced an antioxidant defense, as indicated
by increases in Superoxide dismutase, ascorbate peroxidase, and ascorbic acid, along with decreases in hydrogen peroxide,
lipid peroxidation, and dehydroascorbate/ascorbic acid. However, a higher concentration (250 μM SNP) acted as a pro-oxidant,
thereby raising the levels of hydrogen peroxide, lipid peroxidation, and dehydroascorbate/ascorbic acid while diminishing
ascorbic acid, ascorbate peroxidase, and the accumulation of secondary metabolites compared with our observations at 100 μM
SNP. Therefore, we conclude that elicitingE. purpurea adventitious roots with a concentration of 100 μM SNP is beneficial to their accumulation of secondary metabolites. 相似文献
5.
Małgorzata Kopyra Magdalena Stachoń-Wilk Edward A. Gwóźdź 《Acta Physiologiae Plantarum》2006,28(6):525-536
Nitric oxide (NO) is a small, ubiquitous molecule, whose physiological function in plants has recently been widely investigated.
It seems that one of its pivotal properties is the antioxidant capacity, enabling plants to alleviate the effects of the oxidized
stress. In this work we investigated the role of NO in soybean (Glycine max L. Cv. Navico) cell suspension treated with cadmium. Sodium nitroprusside (SNP), nitric oxide donor, markedly decreased the
negative influence of Cd2+ on cell growth. It was also found to stimulate superoxide dismutase (SOD, EC 1.15.1.1). Using specific fluorochromes — dihydroethidine
(DHE) and 2′,7′- dichlorofluorescein (DCFH-DA) it was shown that NO was very effective in reducing the level of superoxide
anion (O
2
·−
) and hydrogen peroxide, respectively. Furthermore, as evaluated by means of NO specific fluorochrome 4,5-diaminofluorescein
diacetate (DAF-2DA), increased production of NO was found in Cd-treated cells. In cadmium-stressed cells SNP lowered the level
of oxidized proteins.
Our results suggest that the antioxidant properties of nitric oxide in Cd-treated soybean cells rely mainly on its ability
to direct scavenging of ROS and stimulation of the antioxidant system. 相似文献
6.
The effects of sodium nitroprusside (SNP) on callus induction and shoot regeneration of Dioscorea opposite Thunb. have been studied. Application of 40 μM of SNP depresses accumulation of H2O2 in tuber explants of Dioscorea opposita markedly. Supplementation of 40 μM of SNP to the Murashige and Skoog medium with combinations of benzylaminopurine (3 mg dm−3) and naphthaleneacetic acid (0.5 mg dm−3) reduces the browning of explants and increases the frequency of callus induction from tuber explants significantly. The
regeneration frequency of adventitious shoot shows a significant increase in the presence of SNP. Further analysis indicates
that treatment with 40 μM of SNP results in significant decreases in catalase and peroxidase activity, while increasing the
activity of superoxide dismutase. Supplementation with 40 μM of SNP also promotes the accumulation of non-enzymic antioxidants,
including proline and glutathione. The effects on callus induction and shoot regeneration promoted by SNP were reversed by
the nitric oxide (NO) scavenger 2-(4-carboxyphenyl)- 4,4,5,5- tetramethylimidazoline-1-oxyl-3-oxide. These results indicate
that the exogenously applied NO-donor SNP alleviates browning of tuber explants by reducing H2O2 accumulation, thereby promoting a higher in vitro proliferation frequency of D. opposita. 相似文献
7.
Nitric oxide (NO) is a highly reactive, membrane-permeable free radical, which has recently emerged as an important signalling
molecule and antioxidant. Here we investigated the protective effect of NO against the toxicity caused by excess CuSO4 (50 μM) in the adventitious roots of mountain ginseng. It was found that NO donor, sodium nitroprusside (SNP), was effective
in reducing Cu-induced toxicity in the mountain ginseng adventitious roots. Protective effect of SNP, as indicated by extent
of lipid peroxidation, was reversed by incorporation of 2-(4-carboxy-2-phenyl)-4,4,5,5-tetramethyl-imidazoline-1-oxyl-3-oxide
(CPTIO), a NO scavenger, in the medium suggesting that the protective effect of SNP is attributable to NO released, which
was revealed from in situ confocal laser scanning microscopic localization of NO in the adventitious roots of mountain ginseng.
Results obtained in the present study suggest that reduction of excess Cu-induced toxicity by SNP is most likely mediated
through the modulation in the activities of antioxidant enzymes involved in H2O2 detoxification (catalase, peroxidase, ascorbate peroxidase) and in the maintenance of cellular redox couples (glutathione
reductase), and contents of molecular antioxidants (particularly non-protein thiol, ascorbate and its redox status). Exogenous
NO supply also improved the activity of superoxide dismutase, an enzyme responsible for O2
·− dismutation, and NADPH oxidase, an enzyme responsible for O2
·− generation, in excess Cu supplied adventitious roots of mountain ginseng. 相似文献
8.
The goal of this research was to measure in vitro the inhibitory constants of the antioxidants ascorbic and uric acid in urine, with lucigenin enhanced chemiluminescence (CL)
in Fenton’s system. Maximum CL emission is registered in urine containing H2O2 (5·10−4 M), Fe2+ (5·10−5 M), EDTA (5·10−5 M), and chemical enhancer lucigenin (10−4 M) at pH 5.5 and 36°C. Ascorbic acid exhibits up to 4-fold stronger antioxidant effect than uric acid. The constants of antioxidant
inhibition in urine were measured at concentrations 10−3 and 10−4 M: for ascorbic acid, 5.92 ± 0.04 and 24.05 ± 1.82 μmol·sec−1; for uric acid, 1.60 ± 0.02 and 21.45 ± 0.97 μmol·sec−1, respectively. Three phases of CL kinetics of urine are well observed: spontaneous CL (0–10 sec), fast flash of CL (10–50
sec), and latent period (50–300 sec). The antioxidant efficiency of ascorbic and uric acids in the final stage of catabolic
processes in the body is discussed.
Published in Russian in Biokhimiya, 2006, Vol. 71, No. 8, pp. 1062–1065. 相似文献
9.
Badawi JK Li H Langbein S Kamp S Guzman S Bross S 《Journal of comparative physiology. B, Biochemical, systemic, and environmental physiology》2006,176(5):429-439
The inhibitory effects of different calcium antagonists on contractions of isolated porcine detrusor muscle were investigated. Suppression of the maximum potassium-induced contraction and electrically generated contractions by nifedipine, verapamil and diltiazem were investigated. Furthermore, concentration–response curves of carbachol after pretreatment with the L-type antagonists nifedipine, verapamil, diltiazem, nimodipine and the T-type antagonist mibefradil at different concentrations were performed. Nifedipine significantly reduced the potassium-induced maximum contraction to 89, 60, 21, 8 and 4% (10−9–10−5 M). Verapamil and diltiazem significantly reduced it to 64, 30 and 5% (10−7–10−5 M) or 79, 27, 7 and 1% (10−7–10−4 M), respectively. Nifedipine, verapamil and diltiazem significantly reduced the electrically generated contraction to 55, 36, 34 and 25% (10−7–10−4 M), 71, 32 and 2% (10−6–10−4 M), 96, 78, 38 and 5% (10−7–10−4 M), respectively. pD2 values of nifedipine, verapamil and diltiazem amounted to 7.07, 5.56 and 5.40 and differed significantly. After pretreatment with nifedipine at 10−6 M, the concentration–response curve of carbachol was nearly suppressed. The effects of nimodipine, verapamil and diltiazem were smaller. Mibefradil caused only at 10−5 M a significant reduction. All investigated L-type calcium antagonists were strong inhibitors of the examined contractions. Nifedipine showed the biggest inhibitory effect. 相似文献
10.
In roots of Pisum sativum seedlings, the average lag-time required for initiation of the gravitropic response was reduced proportionally to the concentration
of 24-epibrassinolide (EBL) added to the root solution (range of 10−13 to 10−8 M concentrations). A treatment with clotrimazole, a compound inhibiting steroid synthesis, prevents initiation of the gravitropic
response. This effect was partly reverted by addition of EBL. From analysis of variability in the populations, it is suggested
that BR conditions the root curvature through a gravitropic-induced change in sensitivity to the PGRs regulating cell elongation. 相似文献
11.
Jennings BL Bell JD Hyodo S Toop T Donald JA 《Journal of comparative physiology. B, Biochemical, systemic, and environmental physiology》2007,177(5):557-567
This study investigated vasodilator mechanisms in the dorsal aorta of the elephant fish, Callorhinchus milii, using anatomical and physiological approaches. Nitric oxide synthase could only be located in the perivascular nerve fibres
and not the endothelium of the dorsal aorta, using NADPH histochemistry and immunohistochemistry. In vitro organ bath experiments
demonstrated that a NO/soluble guanylyl cyclase (GC) system appeared to be absent in the vascular smooth muscle, since the
NO donors SNP (10−4 mol l−1) and SIN-1 (10−5 mol l−1) were without effect. Nicotine (3 × 10−4 mol l−1) mediated a vasodilation that was not affected by ODQ (10−5 mol l−1), l-NNA (10−4 mol l−1), indomethacin (10−5 mol l−1), or removal of the endothelium. In contrast, the voltage-gated sodium channel inhibitor, tetrodotoxin (10−5 mol l−1), significantly decreased the dilation induced by nicotine, suggesting that it contained a neural component. Pre-incubation
of the dorsal aorta with the calcitonin gene-related peptide (CGRP) receptor antagonist, CGRP8–37 (10−6 mol l−1) also caused a significant decrease in the nicotine-induced dilation. We propose that nicotine is mediating a neurally-derived
vasodilation in the dorsal aorta that is independent of NO, prostaglandins and the endothelium, and partly mediated by CGRP. 相似文献
12.
Yamaguchi M Hamamoto R Uchiyama S Ishiyama K 《Molecular and cellular biochemistry》2007,303(1-2):83-88
The effect of various flavonoids, which are present in food and plants, on bone calcium content and osteoclastogenesis were
investigated to compare action of flavonoid on bone formation and bone resorption in vitro. Rat femoral-diaphyseal (cortical
bone) and -metaphyseal (trabecular bone) tissues were cultured for 48 h in Dulbecco’s modified Eagle’s medium (high glucose)
supplemented with antibiotics and bovine serum albumin. Amoung quercetin, myricetin, kaempferol, isorhamnetin, curcumin, hesperidin,
or astaxanthin in the range of 10−7–10−5 M, culture with quercetin (10−6 or 10−5 M) caused a significant increase in diaphyseal calcium content. Such an effect was not seen in other compounds. Mouse bone
marrow cells were cultured for 7 days in the presence of parathyroid hormone (PTH; 10−7 M), a bone-resorbing factor, in vitro. Culture with PTH caused a significant increase in osteoclast-like cell formation. This
increase was significantly inhibited in the presence of quercetin, myricetin, kaempferol, isorhamnetin, or curcumin in the
range of 10−8–10−6 M. Such an effect was not seen in the case of hesperidin or astaxanthin. In addition, culture with PTH (10−7 M) caused a significant decrease in diaphyseal calcium content. This decrease was completely prevented in the presence of
quercetin, myricetin, kaempferal, or isorhamnetin of 10−6 M. This study demonstrates that various flavonoids have a potent inhibitory effect on osteoclastogenesis and bone resorption
rather than bone formation in vitro. Among various flavonoids, quercetin had a stimulatory effect on bone formation and an
inhibitory effect on bone resorption in vitro. 相似文献
13.
Dubey PK Tripathi V Singh RP Saikumar G Nath A Pratheesh Gade N Sharma GT 《Theriogenology》2012,77(2):280-291
The present study was designed to investigate the expression of nitric oxide synthase (NOS) isoforms in buffalo ovarian preantral (PFs), antral (AFs) and ovulatory (OFs) follicles (Experiment 1); effect of NO on in vitro survival and growth of PFs (Experiment 2) and NOS activity in immature oocytes by NADPH-diaphorase test (Experiment 3). In Experiment 1, NOS isoforms (neuronal, inducible and endothelial) were localized immunohistochemically; mRNA and protein expression was analyzed by semi-quantitative RT-PCR and western blot, respectively. In Experiment 2, PFs were isolated by micro-dissection method from buffalo ovaries and cultured in 0 (control), 10−3, 10−5, 10−7 and 10−9 M sodium nitroprusside (SNP). PFs were further cultured with 10−5 M SNP + 1.0 mM Nω-nitro-L-arginine methyl ester (L-NAME) or 1.0 μg/ml hemoglobin (Hb) to examine the reversible effect of SNP. Immunohistochemical studies demonstrated that inducible nitric oxide synthase (iNOS) immunoreactivity was predominantly localized in granulosa and theca cells whereas, neuronal (nNOS) and endothelial (eNOS) nitric oxide synthase in the theca, granulosa and cumulus cells of PFs, AFs and OFs. The amount of mRNA as well as protein of nNOS and eNOS was found similar between different stages of follicles. In contrast, higher level of iNOS mRNA was observed in OFs and protein in the AFs. Higher doses of SNP (10−3, 10−5, 10−7 M) inhibited (P < 0.05) while, lower dose of SNP (10−9 M) stimulated (P < 0.05) the survival, growth, and antrum formation of PFs. The inhibitory effects of SNP were reversed by Hb, while L-NAME was not found effective. In conclusion, expression of NOS isoforms mRNA and protein in PFs, AFs, and OFs and NOS enzyme activity in immature follicular oocytes suggest a role for NO during ovarian folliculogenesis in buffalo. NO plays a dual role on growth and survival of PFs depending on its concentration in the culture medium. 相似文献
14.
A sand culture experiment was conducted to study ameliorative role of 28-homobrassinolide (HBL) in Brassica juncea seedlings raised from the seeds treated with water, or 10−10, 10−8 and 10−6 M 28-homobrassinolide (HBL) and grown in the presence of copper (50, 100 and 150 mg kg−1 sand) and sampled at 30 days after sowing. The plants grown in the presence of copper exhibited a significant decline in growth, chlorophyll and photosynthetic parameters. However, the activity of antioxidant enzymes: catalase (E.C. 1.11.1.6), peroxidase (E.C. 1.11.1.7) and superoxide dismutase (E.C. 1.15.1.1) and the content of proline increased in the plants grown under copper stress and/or raised from treatment with HBL. However, H2O2 content increased significantly in copper-treated plants and decreased in plants given HBL treatment. Treatment of seeds with HBL improved the growth, photosynthetic parameters and antioxidant enzymes and also improved in the plants grown under copper stress. The elevated antioxidant enzyme and proline might be responsible to overcome the toxic effects of copper in B. juncea. 相似文献
15.
《Saudi Journal of Biological Sciences》2016,23(6):698-705
A study was undertaken to examine the morpho-physiological alterations under different concentrations of 28-homobrassinolide (HBL) in two contrasting varieties of Vigna radiata. Sterilized seeds of V. radiata (T-44 and PDM-139) were inoculated with specific Rhizobium and allowed to grow and then 14 day old seedlings were exposed to different concentrations (0, 10−10, 10−8, or 10−6 M) of HBL and allowed to grow under natural environmental conditions. At the 15 and 21 day stage, plants were harvested to evaluate various parameters. Results clearly indicated that growth bio-markers, accumulation of proline and activities of various antioxidant enzymes increased significantly in T-44 at a later stage of growth in the presence of HBL whereas, 10−8 M showed the most promising response. It is concluded that HBL modifies the physiological functions and biochemical metabolism of V. radiata by increasing photosynthetic efficiency at an early stage of growth and antioxidant system in T-44 at a later stage of plant growth that are manifested in growth at later stages. It is believed that increased accumulation of proline and enhanced antioxidant system provide strength to the plants to withstand environmental cues. 相似文献
16.
Q. Fariduddin S. Khanam S. A. Hasan B. Ali S. Hayat A. Ahmad 《Acta Physiologiae Plantarum》2009,31(5):889-897
To investigate the effect of exogenously applied 28-homobrassinolide (HBL) on drought-stressed plants, photosynthesis and
antioxidant systems were examined in Indian mustard (Brassica juncea L.). Seedlings of Indian mustard were subjected to drought stress for 7 days at the 8–14 (DS1)/15–21 (DS2) days’ stage of
growth and then returned to normal conditions of growth. These seedlings were sprayed with HBL (0.01 μM) at the 30-day stage
and were sampled at 60 days to assess the changes in growth, photosynthesis and antioxidant enzymes. Plants exposed to stress
at either of the stages of growth exhibited a significant decrease in growth and photosynthesis. The exposure of plants to
stress at an earlier stage (DS1) was more inhibitory than that at a later stage (DS2). However, the follow-up treatment with
HBL significantly improved the values of these parameters and also overcame the inhibitory effect of water stress. The activity
of antioxidant enzymes [catalase (E.C. 1.11.1.6), peroxidase (E.C. 1.11.1.7) and superoxide dismutase (E.C. 1.15.1.1)] and
proline content in leaves exhibited an increase in response to both the treatment factors, where their interaction had an
additive effect. It was, therefore, concluded that the elevated antioxidant system, at least in part, was responsible for
amelioration of the drought stress. 相似文献
17.
The involvement of NO in O2
·− generation, rootlet development and antioxidant defence were investigated in the adventitious root cultures of mountain ginseng.
Treatments of NO producers (SNP, sodium nitroprusside; SNAP, S-nitroso-N-acetylpenicillamine; and sodium nitrite with ascorbic acid), and NO scavenger (PTIO, 2-phenyl-4,4,5,5-tetramethylimidazoline-1-oxyl3-oxide)
revealed that NO is involved in the induction of new rootlets. Severe decline in number of new rootlets compared to the control
under PTIO treatment indicates that NO acts downstream of auxin action in the process. NO producers (SNP, SNAP and sodium
nitrite with ascorbic acid) activated NADPH oxidase activity, resulting in greater O2
·− generation and higher number of new rootlets in the adventitious root explants. Moreover, treatment of diphenyliodonium chloride,
a NADPH oxidase inhibitor, individually or along with SNP, inhibited root growth, NADPH oxidase activity and O2
·− anion generation. NO supply also enhanced the activities of antioxidant enzymes that are likely to be responsible for reducing
H2O2 levels and lipid peroxidation as well as modulation of ascorbate and non-protein thiol concentrations in the adventitious
roots. Our results suggest that NO-induced generation of O2
·− by activating NADPH oxidase activity is related to adventitious root formation in mountain ginseng. 相似文献
18.
L. D. Smirnov Yu. V. Kuznetsov S. Ya. Proskuryakov V. G. Skvortsov T. N. Nosko A. E. Dontsov 《Biophysics》2011,56(2):276-280
The antiradical and NO-inhibiting activities of β-hydroxy(ethoxy) derivatives of nitrous heterocycles (3-hydroxypyridine,
5-hydroxybenzimodazole, and 6-hydroxy(alkoxy)-benzothiazole) have been studied. The antiradical activity has been studied
using a homogeneous hydrophilic chemiluminescent system, and the quenching constants (K
i
) have been determined. For the most reactive compound, 4-methylthiobenzimidazolyl-3-hydroxypyridine, K
i
= 4.5 × 105 M−1. The NO-inhibiting activity was estimated on a model of the endotoxin shock of experimental animals using a spin trap of
nitric oxide radicals based on complexes of iron with sodium diethyldithiocarbamate. It was found that the compounds at doses
of 0.25–1 mmol/kg have both the inhibitory and stimulating action on the production of nitric oxide in the liver of animals.
The results obtained suggest that some derivatives of nitrous heterocycles can be used as effective antioxidant preparations. 相似文献
19.
The plants of mung bean (Vigna radiata L. Wilczek) were raised from the seeds soaked in water (control), IAA or 4-C-IAA (10−6, 10−8 or 10−10 M) for 8 or 12 h. The plants were allowed to grow in a net house and were sampled at 30 and 45 days after sowing (DAS). Both
IAA and 4-Cl-IAA significantly affected the growth (length, fresh and dry mass of roots and shoots), the number of nodules,
their fresh and dry mass and the activity of nitrogenase. However, the contents of nitrogen and carbohydrate exhibited a decrease
in response to both the auxins. 4-Cl-IAA, at a concentration of 10−8 M, generated the best response. Moreover, 4-Cl-IAA at other two concentrations (10−6 and 10−10 M) was much more active than any of the IAA concentration used. 相似文献
20.
Jotaro Igarashi Kazuo Kobayashi Ariki Matsuoka 《Journal of biological inorganic chemistry》2011,16(4):599-609