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Phytotoxicity of cadmium on growing Arachis hypogaea L. seedlings was studied. Seeds were exposed to 25, 50, and 100 μmol/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 μmol/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. 相似文献
245.
普乐泰,是蛋白质的中国汉语音译。鹤壁普乐泰生物科技有限公司是河南大用实业有限公司下属子公司,正如它的名字,普乐泰是一个建立在对大用鸡养殖及加工时产生的废料处理基础上,把废料变成蛋白质、变成宝贝的公司。 相似文献
246.
为了提高污泥蛋白质的提取效率并提高其脱水性,分别采用过硫酸氢钾、过氧化钙及被Fe2+活化后的过硫酸氢钾和过氧化钙预处理污泥,以考察其对污泥脱水性及蛋白质提取效率的影响并选出一种最佳的氧化预处理方式.结果表明,过硫酸氢钾和过氧化钙单独调理时,污泥脱水性有明显提高且蛋白质提取量较高.经Fe2+活化后,虽然污泥比阻(FSR)比单独调理时降低50%以上,但因反应生成具有絮凝效果的Fe3+导致蛋白质提取量大幅降低.结合蛋白提取效率,发现采用0.1 g/gTSS(干物质质量)的过氧化钙单独调理效果最好,此时污泥比阻(FSR)与毛细吸水时间(tCST)分别为0.37×1013m/kg、22.4 s,相比原污泥比阻与毛细吸水时间分别降低78.4%和76.6%,同时蛋白质提取量高达104.52 mg/g TSS,与原污泥相比增加了 80.4%. 相似文献
247.
In order to understand its response towards nickel stress, watercress (Nasturtium o cinale R. Br.) was exposed to nickel (1–25 mg/L)
for 1, 3, 5 and 7 days. The accumulation and translocation of nickel were determined and the influence of nickel on biomass, protein
content and enzymatic antioxidants was examined for both roots and leaves. It was determined that N. o cinale could accumulate
appreciable amounts of Ni in both roots and leaves. Nickel accumulated particularly in the roots of plants. Biomass increased at low
nickel concentrations but certain measurable change was not found at high concentrations. Under stress conditions the antioxidant
enzymes were up-regulated compared to control. An increase in protein content and enzyme activities was observed at moderate
exposure conditions followed by a decline at both roots and leaves. The maximum enzyme activities were observed at di erent exposure
conditions. Our results showed that N. o cinale had the capacity to overcome nickel-induced stress especially at moderate nickel
exposure. Therefore, N. o cinale may be used as a phytoremediator in moderately polluted aquatic ecosystems. 相似文献
248.
KHADRO Basm NAMOUR Philippe BESSUEILLE Franc?ois LEONARD Didier JAFFREZIC-RENAULT Nicole 《环境科学学报(英文版)》2009,21(4):545-551
This article describes a conductometric bi-layer based bienzyme biosensor for the detection of proteins as a marker of organic matter
in rivers. Proteins were chosen to be used as indicators of urban pollution. The working mechanism of the bienzyme biosensor is based
on the enzymatic hydrolysis of proteins into several fractions (peptides and amino acids), which results in a local conductivity change
depending of the concentration of proteins. In this work, we began with the optimization of biosensor response using bovine serum
albumin (BSA) as standard protein. For this objective seven enzymatic biosensors were prepared: four enzymatic sensors with only one
layer of enzyme (proteinase K, trypsin, pronase or protease X) and three other enzymatic sensors with two layers (first layer: membrane
containing proteinase K; second layer: one of the three other enzymes: trypsin, pronase or protease X). The biosensors were obtained
through the deposition of enzymatic layers and the cross-linking process between enzymes and BSA in saturated glutaraldehyde vapour.
The response of the various biosensors, described previously, were compared with the values of total organic carbon (TOC), and those of
organic nitrogen (Norg), as determined by the laboratory accredits (CEMAGREF of Lyon) using the traditional method of analysis (NF
EN 1484, infrared spectroscopy) and (NF EN 25663, mineralization/colorimetry assay) respectively for each water sample obtained
from di erent sites in Lyon (France). The linear correlations obtained with the response of the seven biosensors showed the most
important indices of correlations for the biosensor with two enzymatic layers: proteinase K + pronase (pkp). The optimum conditions
for the preparation of the pkp biosensor increased the sensitivity and gave a limit of quantification of 0.583 g/L for TOC and 0.218
g/L for Norg in water samples. This sensor shows good reproducibility (2.28%), a capacity to be used at temperatures range 10–
30°C (depending on the season) and moreover a long lifetime (5 weeks). 相似文献
249.
《环境科学与技术》2021,44(7):140-144
为探究生物炭对活性污泥特征及脱氮除磷的影响,该文在中温条件下,采用序批式反应器,考察了不同类型基质生物炭对活性污泥处理城镇低C/N废水的影响。结果表明,生物炭降低了污泥体积指数,提高了混合液挥发性悬浮固体,利于微生物的增殖。此外,生物炭提高了活性污泥胞外聚合物(EPS)含量,在鸡粪生物炭、玉米秸秆生物炭和污泥生物炭存在的组别内,EPS的含量分别升高至41.3、46.5和39.8 mg/g,显著高于对照组。生物炭主要提高了EPS内蛋白质(PN)的含量,而对多糖(PS)含量影响不显著,进而提高了PN/PS。生物炭强化了活性污泥对氨氮及总磷的去除,而对化学需氧量的影响不显著。生物炭作为载体微生物提供良好附着进而提高微生物活性,此外,生物炭能吸附氨氮与总磷。 相似文献
250.
Studies on Formation of Liquid and Gaseous Formaldehyde-Induced DNA-Protein Crosslinks in Rat Marrow Cells 总被引:1,自引:1,他引:0
甲醛是一种遗传毒物,流行病学研究表明甲醛可能具有诱导白血病的作用,然而甲醛诱导白血病的机制目前还不清楚. 以不同浓度液态和气态甲醛对大鼠骨髓细胞进行染毒,采用KCl-SDS 法检测了骨髓细胞 DNA-蛋白质交联程度,并采用单细胞凝胶电泳技术(彗星实验)检测了骨髓细胞 DNA 链断裂程度. 研究结果表明:与对照组相比,低浓度甲醛(液态甲醛浓度为:5μmol·L-1和25μmol·L-1;气态甲醛浓度为:0.5mg·m-3 和 1.0mg·m-3)可以引起 DNA断裂水平显著增高 (p<0.01);而高浓度甲醛 (液态甲醛浓度为:125μmol·L-1 和 625μmol·L-1;气态甲醛浓度为:3.0mg·m-3)则可以引起 DNA-蛋白质交联水平显著增高(p<0.01; p<0.05). 研究结果提示:甲醛染毒可以导致大鼠骨髓细胞DNA的损伤,暗示甲醛诱导白血病具有高度的可能性. 相似文献