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61.
The effect of exogenous silicon (Si) on the growth, boron (B) uptake, stomatal conductance, lipid peroxidation (MDA), membrane permeability, lipoxygenase activity (LOX), proline and H2O2 accumulation, non-enzymatic antioxidant activity (AA) and the activities of major antioxidant enzymes (superoxide dismutase, SOD; catalase, CAT and ascorbate peroxidase, APX) of spinach were investigated under greenhouse conditions. Spinach plants were grown with 0 or 30 mg kg−1 B combined with 0 and 150 mg kg−1 Si. The severity of leaf symptoms of B toxicity was lower when the plants were grown with 150 mg kg−1 Si. Silicon supplied to the soil with high B counteracted the deleterious effects of B on root and shoot growth. Application of B significantly increased B concentration in shoot and in root tissues. However, Si decreased B concentration in the shoots but increased it in the roots. Shoot tissues of spinach contained higher B than the roots in all treatments. Applied Si increased the Si concentration of the root and shoot. Stomatal conductance of the plants was decreased by B, but was increased by Si. The concentrations of H2O2 and proline were increased by B toxicity but were decreased by Si applied to plants. Boron toxicity increased the membrane permeability, MDA content and LOX activity of excised leaves of spinach. Applied Si ameliorated the membrane deterioration significantly. Compared with control plants, the activities of AA, SOD, CAT and APX in B-stressed plants without Si applied increased, and application of Si decreased their activities under toxic B conditions. Based on the present work, it can be concluded that Si alleviates B toxicity by preventing oxidative membrane damage and also translocation of B from root to shoots. To our knowledge, this is the first report on the effect of Si in improving B tolerance in spinach. 相似文献
62.
旨在探讨BRA-90花青素对肝损伤具有一定的保护作用和抗氧化作用,建立了一次性力竭游泳运动模型,采用邻苯三酚法检测各组小鼠肝脏组织中超氧化物歧化酶(SOD)的活性,分析比较给药组和对照组肝脏指标变化情况。结论得出BRA-90花青素具有一定抗氧化作用,为BRA-90花青素在各方面的进一步应用和开发提供实验依据。 相似文献
63.
Characterization of Barley Leaf Tolerance to Drought Stress by Chlorophyll Fluorescence and Electron Paramagnetic Resonance Studies 下载免费PDF全文
M. Filek M. Łabanowska J. Kościelniak J. Biesaga‐Kościelniak M. Kurdziel I. Szarejko H. Hartikainen 《Journal of Agronomy and Crop Science》2015,201(3):228-240
Two kinds of barley genotypes with various water‐stress tolerances, tolerant Cam/B1 and sensitive Maresi, were subjected to 10‐day soil‐drought stress in seedling and flag leaf developmental phases. After this time, both genotypes regardless of the growth stage showed a decrease in quantum yield of PSII photochemistry (ΦPSII) upon stress treatment; however, this effect was stronger in the sensitive plants than in the tolerant ones. The drought stress in the flag leaf stage was associated with an increase in superoxide dismutase (SOD) level in both genotypes, whereas in seedlings, this effect was observed only for Maresi. The activity of other enzymes (catalase and peroxidase) was changed only in small degree. An increase in proline levels and activities of Δ1‐pyrroline‐5‐carboxylate synthetase (P5CS) and ornithine delta‐aminotransferase (OAT) were observed independently of genotype and the phase of plant development, whereas the activity pyruvate dehydrogenase (PDH) decreased in tolerant genotype. Moreover, changes in the concentration of monocarbohydrates (glucose and fructose) and dicarbohydrates (saccharose, raffinose and maltose) were found: in seedlings, the amount of all soluble sugars increased, while in flag leaves decreased. The drought treatment resulted in a drop in starch level in the tolerant genotype, but in the sensitive one, the content of this substance increased in both developmental stages. EPR studies allowed the determination of the amount and character of organic radicals present in leaves. In control conditions, the content of these radical species was higher in the sensitive genotype than in tolerant one and decreased upon water stress, with the exception of flag leaves of the sensitive plant. Simulation procedure revealed four types of signals in the EPR spectra. One of them was attributed to a chlorophyll a cation and decreased upon drought. The second, ascribed to semiquinone radicals, reflected the redox balance disturbed by water deficit. The two remaining signals were connected with carbon‐centred radicals situated in the carbohydrate matrix. Their number was correlated with starch concentration. 相似文献
64.
抗氧剂及单果包装处理控制苹果梨的黑皮病 总被引:5,自引:1,他引:5
苹果梨采后用4种抗氧化剂及5种类型单果包装处理控制黑皮病的研究结果表明:4种抗氧化剂均可明显降低黑皮率及表皮褐变度,使用浓度越高,效果就越好,其中以亚硫酸氢钠效果最好,乙氧基喹次之;5种类型单果包装均能显著减少黑皮率及表皮褐变度,其中以薄膜袋+发泡网袋效果最好,包果纸+发泡网袋次之;药物及单果包装配合处理可使处理的效果叠加。 相似文献
65.
Ander Arando Juan Vicente Delgado Alejandra Bermúdez-Oria José Manuel León África Fernández-Prior Sergio Nogales Carlos C. Pérez-Marín 《Reproduction in domestic animals》2020,55(3):325-332
The aim of the present study was to evaluate the effect of the addition of two olive oil-derived antioxidants, hydroxytyrosol (3,4-dihydroxyphenylethanol, HT) and 3,4-dihydroxyphenylglycol (DHPG), on ovine semen during liquid storage at 5°C and 15°C. Semen was collected, pooled, diluted and then divided into aliquots supplemented with different concentrations (5 μg/ml, 10 μg/ml, 50 μg/ml and 100 μg/ml) of HT, DHPG and a mixture (MIX) of both antioxidants. Sperm motility characteristics were assessed in the different samples at 0, 6, 24, 48, 72 and 96 hr after cooling, and a fertility trial was also conducted. The results showed that the antioxidant addition did not significantly improve total and progressive motility in ovine cooled sperm maintained at 15° or 5°C. However, in samples stored at 5°C, LIN (48, 72, 96 hr), STR (0 hr) and WOB (0, 48, 72, 96 hr) values significantly decreased in comparison with control treatment when high antioxidant concentrations were added (MIX100 or HT100). When samples were maintained at 15°C, MIX50 showed significantly higher VCL values than the control treatment after 6 hr cooling, and MIX100 showed significantly lower VCL values at 96 hr after cooling. According to the artificial insemination trial, no significant differences were observed when antioxidants were added. In conclusion, the use of HT and DHPG showed small impact in sperm motility and fertility was not affected (nor detrimentally nor positively) when insemination was carried out using antioxidant-supplemented liquid sperm. 相似文献
66.
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68.
E. Vossen M. Ntawubizi G. Huyghebaert S. De Smet 《Journal of animal physiology and animal nutrition》2011,95(2):198-205
In this study, the effect of dietary antioxidants on the plasma oxidative status of growing birds fed a diet rich in polyunsaturated fatty acids was investigated. One‐day‐old broilers were fed for 42 days a diet containing 4% linseed oil and supplemented with single plant extracts rich in antioxidants (natural tocopherols, rosemary, grape seed, green tea, tomato) or a combination of some of these plant extracts, in two different total doses (100 and 200 mg product/kg feed). A diet with synthetic antioxidants with and without α‐tocopheryl acetate (200 mg/kg feed) were also included. The plasma oxidative status was evaluated measuring the ferric reducing ability of plasma (FRAP), the superoxide dismutase (SOD) and glutathione peroxidase (GSH‐Px) activity. Lipid peroxidation was measured by thiobarbituric acid‐reactive substances (TBARS). No significant effect of the dietary treatments was observed for FRAP as well as for TBARS. However, diet affected GSH‐Px activity (p = 0.002) and a trend for an effect on SOD activity was observed (p = 0.084). A higher GSH‐Px activity was found for 200 mg/kg tomato extract and natural α‐tocopherol in relation to the corresponding 100 mg/kg treatment, and the lowest GSH‐Px activity was measured for the synthetic antioxidants treatment. The lowest and highest SOD activity were found for the 200. and 100 mg/kg treatment with tomato extract respectively. In conclusion, the oxidative status and lipid oxidation of plasma in broilers was not affected by feeding natural antioxidant extracts at the doses in the present study, but some changes in antioxidant enzyme activities were observed, of which the implication remains to be elucidated. 相似文献
69.
高温胁迫影响食用菌的品质和产量,由高温引起的氧化胁迫是导致损伤的主要原因。以肺形侧耳(Pleurotus pulmonarius)热敏感菌株CCMSSC 00494和耐热菌株CCMSSC 00499为试验材料,研究了外源海藻糖对其菌丝体高温胁迫下氧化损伤的缓解效应。结果表明,高温(40 ℃)胁迫48 h,热敏感菌株中硫代巴比妥酸反应物(TBARS)含量(代表氧化损伤程度)高于耐热菌株。外源海藻糖处理可以显著降低高温胁迫下菌丝体内产生速率、H2O2含量、脂氧合酶(LOX)活性和TBARS含量水平,缓解高温胁迫所引发的氧化损伤。另外,外源海藻糖对超氧化物歧化酶(SOD)活性有保护和提高的作用,对过氧化氢酶(CAT)和抗坏血酸过氧化物酶(APX)活性有抑制作用,对过氧化物酶(POD)活性影响不明显。外源海藻糖对热敏感菌株的保护效应高于耐热菌株。 相似文献
70.
Maria Alessandra Gammone Eugenio Gemello Graziano Riccioni Nicolantonio D’Orazio 《Marine drugs》2014,12(5):2357-2382
An enriched diet with antioxidants, such as vitamin E, vitamin C, β-carotene and phenolic compounds, has always been suggested to improve oxidative stress, preventing related diseases. In this respect, marine natural product (MNP), such as COX inhibitors, marine steroids, molecules interfering with factors involved in the modulation of gene expression (such as NF-κB), macrolides, many antioxidant agents, thermogenic substances and even substances that could help the immune system and that result in the protection of cartilage, have been recently gaining attention. The marine world represents a reserve of bioactive ingredients, with considerable potential as functional food. Substances, such as chitin, chitosan, n-3 oils, carotenoids, vitamins, minerals and bioactive peptides, can provide several health benefits, such as the reduction of cardiovascular diseases, anti-inflammatory and anticarcinogenic activities. In addition, new marine bioactive substances with potential anti-inflammatory, antioxidant and thermogenic capacity may provide health benefits and performance improvement, especially in those who practice physical activity, because of their increased free radical and Reacting Oxygen Species (ROS) production during exercise, and, particularly, in athletes. The aim of this review is to examine the potential pharmacological properties and application of many marine bioactive substances in sports. 相似文献