分子识别作用下光催化降解偶氮染料酸性红GR

合成了β-环糊精(β-CD)与偶氮染料酸性红GR(ARGR)的包结物,并采用红外光谱仪对ARGR、β-CD及β-CD与ARGR的包结物进行了表征,表征结果显示,β-CD与ARGR的包结物的特征峰的峰形和强度与β-CD相似,但峰位有明显的偏移,说明ARGR进入了β-CD空腔与β-CD发生了分子识别作用。采用TiO2作为催化剂,研究了β-CD分子识别后ARGR的光催化降解行为,实验结果表明,在ARGR质量浓度为20.0 mg/L、β-CD浓度为1.8×10-5 mol/L、体系pH为4.0、TiO2加入量为1.0 g/L、光催化反应时间为60 min的条件下,经β-CD分子识别后ARGR的光催化降解率可达100%。     

二噁英类物质CALUX报告基因法在造纸行业的应用探究

选择典型造纸厂,采用化学激活报告基因法(CALUX)测定造纸过程中废水和纸浆中的二噁英类物质,并将部分样品测定结果与高分辨气相色谱-高分辨质谱(HRGC-HRMS)法测定结果作线性回归,换算系数为0.21,表明CALUX可用于造纸行业废水中二噁英类物质的快速筛查。将CALUX用于测定造纸厂废水中二噁英类物质,结果表明用含元素氯的漂白工艺会产生大量二噁英类物质,其中漂白废水中的目标物毒性当量浓度最高,经处理后可达到国家排放标准;而用无元素氯的漂白工艺,二噁英类物质的产生量会大幅降低。     

Plant steroid hormones produced under Ni stress are involved in the regulation of metal uptake and oxidative stress in Brassica juncea L

Brassinosteroids (BRs) are involved in the amelioration of various biotic and abiotic stresses. With an aim to explore the role of BRs under heavy metal stress, plants of Brassica juncea L. were grown in pots. The plants were subjected to various concentrations of Nickel metal (0.0, 0.2, 0.4 and 0.6 mM) and harvested on 60th day in order to observe the expression of these hormones. The isolated BRs from the leaves of Brassica plants characterized by GC-MS include 24-Epibrassinolide (24-EBL), Castasterone, Dolicholide and Typhasterole. The effect of isolated 24-EBL was studied on Ni metal uptake and antioxidative defense system in 60 d old plants of Brassica. It was observed that 24-EBL significantly increased the activities of stress ameliorating enzymes and lowered the metal uptake in plants. This is the first report in B. juncea L. plants showing the expression of BRs under metal treatments and effect of the isolated 24-EBL on metal uptake and in oxidative stress management.     

紫外辐照-催化湿式过氧化氢氧化技术处理酸性大红GR染料废水

采用自制的负载型CuO-ZnO-CeO2/γ-Al2O3催化剂,常温常压下通过紫外辐照-催化湿式氧化技术处理酸性大红GR模拟染料废水。考察了催化剂加入量、H2O2加入量、废水pH、反应时间、初始酸性大红GR质量浓度等对废水脱色率的影响。实验得到最佳工艺条件为初始酸性大红GR质量浓度200mg/L,催化剂加入量10.0g/L,H2O2加入量2.0mL/L,废水pH4,反应时间2h。最佳工艺条件下废水脱色率达99.33%。     

Hydroxytyrosol, the phenolic compound of olive oil protects human PBMC against oxidative stress and DNA damage mediated by 2,3,7,8-TCDD

The protective effect of hydroxytyrosol (HT), a strong antioxidant compound from extra virgin olive oil, against TCDD induced toxicity was investigated in human peripheral blood mononuclear cells (PBMC). PBMC (1 × 10⁶ cells mL⁻¹) were divided into four groups and were incubated in a CO₂ incubator (5% CO₂) for 12 h with vehicle, TCDD (10 nM), TCDD + HT (10 nM + 100 μM) and HT alone (100 μM) respectively. To clarify the role of HT against TCDD induced cytotoxicity, oxidative stress and the levels of antioxidant enzymes were assessed. Incubation of PBMC with TCDD significantly decreased cell viability, catalase (CAT) and glutathione peroxidase (GPx) and increased the levels of superoxide dismutase (SOD), glutathione reductase (GR) and oxidative stress markers such as lipid peroxidation products (LPO), protein carbonyl content (PCC) and reactive oxygen species (ROS). Whereas, HT had an effective antioxidant property as observed by the increased cell viability, normalization of antioxidant enzymes and decreased levels of LPO, PCC and ROS in PBMC co-treated with HT and TCDD. Apoptosis detection and comet assay results shows that HT, by acting as an antioxidant, prevents the damage to DNA induced by TCDD. In addition light microscopic and histopathological observations revealed that the cells are apoptotic and degenerated during TCDD treatment, whereas cells showed intact morphology during co-treatment with HT. On the whole, the results reveal that HT exerts a promising antioxidant potential in protecting the PBMC against TCDD induced oxidative stress, which might be due to the presence of catechol moiety in its structure.     

Fate of ah receptor agonists during biological treatment of an industrial sludge containing explosives and pharmaceutical residues

GOAL, SCOPE AND BACKGROUND: Sweden is meeting prohibition for deposition of organic waste from 2005. Since 1 million tons of sludge is produced every year in Sweden and the capacity for incineration does not fill the demands, other methods of sludge management have to be introduced to a higher degree. Two biological treatment alternatives are anaerobic digestion and composting. Different oxygen concentrations result in different microbial degradation pathways and, consequently, in a different quality of the digestion or composting residue, It is therefore necessary to study sludge treatment during different oxygen regimes in order to follow both degradation of compounds and change in toxicity. In this study, an industrial sludge containing explosives and pharmaceutical residues was treated with anaerobic digestion or composting, and the change in toxicity was studied. Nitroaromatic compounds, which are the main ingredients of both pharmaceutical and explosives, are well known to cause cytotoxicity and genotoxicity. However, little data are available concerning sludge with nitroaromatics and any associated dioxin-like activity. Therefore, we studied the sludge before and after the treatments in order to detect any changes in levels of Ah receptor (AhR) agonists using two bioassays for dioxin-like compounds. METHODS: An industrial sludge was treated with anaerobic digestion or composting in small reactors in a semi-continuous manner. The same volume as the feeding volume was taken out daily and stored at -20 degrees C. Sample preparation for the bioassays was done by extraction using organic solvents, followed by clean up with silica gel or sulphuric acid, yielding two fractions. The fractions were dissolved in DMSO and tested in the bioassays. The dioxin-like activity was measured using the DR-CALUX assay with transfected H4IIE rat hepatoma pGudluc cells and an EROD induction assay with RTL-W1 rainbow trout liver cells. RESULTS AND DISCUSSION: The bioassays showed that the sludge contained AhR agonists at levels of TCDD equivalents (TEQs) higher than other sludge types in Sweden. In addition, the TEQ values for the acid resistant fractions increased considerably after anaerobic digestion, resulting in an apparent formation of acid resistant TEQs in the anaerobic reactors. Similar results have been reported from studies of fermented household waste. There was a large difference in effects between the two bioassays, with higher TEQ levels in the RTL-W1 EROD assay than in the DR-CALUX assay. This is possibly due to a more rapid metabolism in rat hepatocytes than in trout hepatocytes or to differences in sensitivities for the AhR agonists in the sludge. It was also demonstrated by GC/FID analysis that the sludge contained high concentrations of nitroaromatics. It is suggested that nitroaromatic metabolites, such as aromatic amines and nitroanilines, are possible candidates for the observed bioassay effects. It was also found that the AhR agonists in the sludge samples were volatile. CONCLUSIONS: The sludge contained fairly high concentrations of volatile AhR agonists. The increase of acid resistant AhR agonist after anaerobic digestion warrants further investigations of the chemical and toxic properties of these compounds and of the mechanisms behind this observation. RECOMMENDATION AND OUTLOOK: This study has pointed out the benefits of using different types of mechanism-specific bioassays when evaluating the change in toxicity by sludge treatment, in which measurement of dioxin-like activity can be a valuable tool. In order to study the recalcitrant properties of the compounds in the sludge using the DR-CALUX assay, the exposure time can be varied between 6 and 24 hours. The properties of the acid-resistant AhR agonists formed in the anaerobic treatment have to be investigated in order to choose the most appropriate method for sludge management.     

氧化剂与新型絮凝剂协同去除酸性大红的研究

选取浓度为25mg/L的酸性大红-GR溶液为模拟染料废水,采用氧化-絮凝耦合工艺,探索了氧化剂种类、絮凝剂种类、废水pH值、氧化剂和絮凝剂投加量对氧化-絮凝耦合处理酸性大红染料的影响,确定最佳处理条件为:酸性大红溶液初始pH值不变,高锰酸钾和PTSS的投加量分别为为20mg/L和10mg/L(以钛离子计),脱色率和COD去除率均最大,分别为96.3%、56.5%。通过FTIR光谱扫描、絮体的显微形貌观察、酸性大红和新型絮凝剂聚硅硫酸钛(PTSS)的表面电动电位随pH值的变化的测定,分析了氧化-絮凝耦合法的反应历程:高锰酸钾破坏酸性大红的发色基团后,自身被还原成新生态二氧化锰胶体;二氧化锰胶体吸附酸性大红及其氧化产物,并被无机高分子絮凝剂PTSS通过电中和及架桥网捕等作用卷裹成絮体。     

H2O2处理酸性大红GR染料废水的研究

通过对废水pH值、H2O2用量、催化剂用量、反应时间、反应温度等工艺条件的考察,确定了H2O2催化氧化处理酸性大红染料废水的最佳工艺条件pH 4、H2O2用量6 mL/L、催化剂用量3 g/L、反应时间100 min、反应温度70℃.在该条件下,COD和色度的去除率分别为76.7%和99.4%;通过反应前后的紫外-可见光光谱分析表明,H2O2催化氧化处理酸性大红GR染料废水有比较好的效果,为该工艺处理酸性大红GR染料废水提供了科学依据.     

荧光素酶报告基因法测定废气中二英类物质

研究二噁英类生物检测法的主要目的是简化二噁英类分析流程,并找出快速检测的结果与HRGC-HRMS(高分辨气相色谱-高分辨质谱)结果之间的换算系数,从而可以利用快速检测的结果和换算系数来推算HRGC-HRMS的结果. 介绍了CALUX(荧光素酶报告基因法)分析废气中二噁英类物质的原理,并采用该方法分析了我国27个废气样品,以期找出其测定结果与HRGC-HRMS结果之间的换算系数. 结果表明,这2种测试方法数据相关性显著,R2为0.994 8,数据间的换算系数为0.379. 试验表明,CALUX法具有很好的推广性,如果再适当增加废气样品的数量,对换算系数进行适当的优化,则所得换算系数可推广.      

O3浓度升高对不同生长期冬小麦叶片抗氧化系统的影响

由于人口的快速增长,人类活动导致近地层O3浓度不断提高,O3浓度升高将对植物、动物和人体健康产生极大的危害.采用开顶式气室(OTC)原位实验方法,研究O3浓度升高对不同生长期冬小麦叶片抗氧化系统的影响,进而分析O3对植物的伤害机制.结果表明,O3浓度升高可导致冬小麦拔节期和抽穗期叶片超氧化物歧化酶(SOD)、过氧化物酶...