酚类化合物对发光细菌的急性毒性和对ETS的抑制研究

研究了5种酚类化合物对发光细菌毒性和活性污泥脱氢酶活性的抑制作用。结果表明,酚类化合物对502海水发光细菌的毒性大小顺序为2,4-二氯苯酚>对硝基苯酚>邻甲基苯酚>苯酚>对氨基苯酚,对应的EC50值分别为4.95、23.90、42.43、83.65和178.75 mg/L。而对活性污泥脱氢酶活性抑制的大小顺序同发光细菌毒性测定结果不太一致,毒性大小顺序为2,4-二氯苯酚>邻甲基苯酚>对氨基苯酚>苯酚>对硝基苯酚,相应的EC50值分别为37、398、575、794和1 333 mg/L。两种毒性测定方法的EC50结果差异比较大,可能和测定方法的特点有关。但仅仅根据单一的、高灵敏度的发光细菌毒性测定结果来调整废水处理工艺中的各项参数而实现对水质的调控,可能会造成处理成本的大幅度地增加,因此根据两种或多种毒性测定方法(其中包括以活性污泥为对象)的测定结果判定有机污染物的毒性更科学。     

Enhancement of innate immune system,survival and yield in Penaeus monodon reared in ponds using Streptococcus phocae PI80

The objective of this study was to evaluate the effect of dietary and water supplementation of probiotic Streptococcus phocae PI80 on growth, immune response and feed utilization of tiger shrimp Penaeus monodon in earthen ponds. The probiotic bacterium S. phocae PI80 was cultured in large fermenter (50 L) by adding additional carbon source in the form of molasses and glucose along with yeast extract as nitrogen source to enrich S. phocae PI80 biomass. This enriched S. phocae PI80 was administered to shrimp in feed (6.5 × 10¹³ bacterial cells mL^?1) as well as in pond water (5 L/pond). Shrimp growth performance was significantly improved (P < 0.05) in 120 days culture when the average body weight of treated molasses + yeast extract (MY) (28.41 ± 0.874 g), glucose + yeast extract (GY) (27.013 ± 0.698 g) was significantly higher than control (23.63 ± 0.684 g). Food conversion ratio FCR was also found to be reduced significantly in ponds treated with probiotics when compared with control pond (1.89 ± 0.09). Vibrio and luminescent bacteria were found to be lower in the treatment receiving MY group, and we hypothesize that this may lead to greater shrimp survival. Furthermore, fermentation product of S. phocae PI80 added to pond water and feed additives enhanced the shrimp immune system. The results indicated that total haemocytes count (THC), phenoloxidase (PO) activity, NBT reductase assay and phagocytic activity significantly increased in shrimps treated with S. phocae PI80. Our study demonstrates that administration of S. phocae PI80 in the water and feed at 6.5 × 10¹³ colony‐forming units (CFU) mL^?1 bacterial cells induce immune modulation and enhances the immune ability of P. monodon in pond‐reared shrimp and increased the shrimp production.     

酚类化合物对发光细菌的急性毒性和对ETS的抑制研究

研究了5种酚类化合物对发光细菌毒性和活性污泥脱氢酶活性的抑制作用。结果表明,酚类化合物对502海水发光细菌的毒性大小顺序为2,4-二氯苯酚>对硝基苯酚>邻甲基苯酚>苯酚>对氨基苯酚,对应的EC50值分别为4.95、23.90、42.43、83.65和178.75 mg/L。而对活性污泥脱氢酶活性抑制的大小顺序同发光细菌毒性测定结果不太一致,毒性大小顺序为2,4-二氯苯酚>邻甲基苯酚>对氨基苯酚>苯酚>对硝基苯酚,相应的EC50值分别为37、398、575、794和1 333 mg/L。两种毒性测定方法的EC50结果差异比较大,可能和测定方法的特点有关。但仅仅根据单一的、高灵敏度的发光细菌毒性测定结果来调整废水处理工艺中的各项参数而实现对水质的调控,可能会造成处理成本的大幅度地增加,因此根据两种或多种毒性测定方法(其中包括以活性污泥为对象)的测定结果判定有机污染物的毒性更科学。     

应用发光细菌法检测饲用抗生素单一及联合毒性的研究

以HgCl2为毒性参照,以等毒性配比法研究了饲用盐酸金霉素、吉他霉素、盐霉素和黄霉素对发光细菌的单一及联合毒性。结果表明:盐酸金霉素、吉他霉素、盐霉素、黄霉素对明亮发光杆菌的急性毒性EC50分别为9.21、146.13、4.24 mg/L和134.68 mg/L,发光细菌的相对发光强度(RLU)随着抗生素浓度的提高而降低,并分别在2~16、25~200、1~8 mg/L和25~200 mg/L范围内呈良好线性关系;多元饲用抗生素对发光细菌具有联合毒性的作用,吉他霉素与盐酸金霉素、盐霉素和黄霉素3种抗生素的二元组合对发光细菌的联合毒性表现为较强的协同作用,而盐酸金霉素、盐霉素和黄霉素两两分别组合对发光细菌的联合毒性表现为拮抗作用;三元及四元抗生素混合体系对发光细菌的联合毒性均表现为拮抗作用。     

Improvement of the Luminescent Performances of CaTiO3:Pr3

Long after-glow red phosphors CaTiO_3:Pr~(3+),X~(3+)( X~(3+)=Gd~(3+),Dy~(3+),Tb~(3+),Eu~(3+)) were prepared by Solid State reaction process. The excitation spectrum, emission spectrum, XRD and the curve of afterglow decay were investigated. The decay curves indicate the luminescent performance is improved by co-doped the other three ions except Gd~(3+). Co-doping with Tb~(3+) and Eu~(3+) the excitation spectrum is a broad band , the main excitation spectrum and the subordinate excitation spectrum are red-shift. The absorption at 458,478,482 nm and 496 nm are increased. The emission spectrum peaking at 614 nm is due to a transition from ~1D_2-~3H_4 of Pr~(3+).The results of XRD reveal there is CaTiO_3 phase and the co-dopant isn't change the crystal field notably.     

饮用水源地预警体系应用研究

对天津市饮用水进行监测研究,结果表明：2013年1月到2013年12月,综合生物毒性检测仪分析结果显示天津饮用水水体无毒,同步自动监测数据的评价结果也显示水质达到地表水Ⅲ类标准,符合饮用水要求,两者结果一致。氨氮与毒性抑制率呈显著负相关（sig＜0．01）。在此期间生物毒性抑制率负值比例非常大,占68．2％,这说明水体营养盐含量较高,富营养化态势较为明显,营养物质的存在为发光细菌的新陈代谢提供了充足的营养素,所以出现生物综合毒性测试中毒性抑制率为负值的现象。     

东莞石马河沿岸土壤重金属污染及生态毒性研究

为研究河水-地下水交互作用对河流沿岸土壤环境质量的影响,以东莞石马河沿岸土壤为研究对象,采集沿岸距离河道不等的6个土壤剖面共31个土样,测定土壤重金属(As、Cd、Cr、Cu、Fe、Mn、Ni、Pb和Zn)含量和土壤水提取液对发光菌的抑制率。结果表明,Cd、Cu、Ni和Zn的含量分别为2.80~11.2mg kg-1、9.70~298mg kg-1、11.4~69.7mg kg-1和40.4~465mg kg-1;Cd的地累积系数为6.06,达到极度污染水平;土壤重金属污染的地累积系数排序为CdZnCuNiCrMnAsPbFe;重金属含量差异与土壤有机质(SOM)含量和土壤微粒组分(63μm)有关,Cr、Cu、Ni、Zn、Mn和Cr、Ni与SOM含量和微粒组分分别呈显著正相关(p0.05或p0.01);土壤剖面毒性单位(∑TU)评价结果为剖面S3S2SbS1S4Sa,其中剖面S3的值最大,为5.51,属于中毒;土壤水提取液对发光菌的抑制率为2.45%~16.5%,为无毒或低毒。     

模拟酸雨对铅锌冶炼废渣重金属释放及生物毒性的影响

为评价酸雨淋洗对铅锌冶炼废渣中重金属释放及生物毒性的影响,以黔西北酸雨严重区域大量堆存的铅锌冶炼废渣堆场为研究对象,对照组以去离子水为浸提剂,分析不同粒径废渣在不同酸度模拟酸雨浸提下重金属的分布特征及生物毒性变化规律。结果表明,与对照相比,模拟酸雨均可不同程度降低铅锌废渣浸出液的pH,废渣粒径越小浸出液的电导率越高。模拟酸雨可提高铅锌冶炼废渣浸出液中Cu、Zn、Cd的浓度,相同条件下,浸出液中重金属浓度总体上随废渣粒径减小呈增加趋势。模拟酸雨可促进废渣中残渣态Cu、Pb、Zn向其他形态转化而增加铅锌废渣堆存的环境风险。进一步分析表明,废渣浸出液中Zn、Cd含量越高浸出液的生物毒性越大,而低浓度范围内废渣浸出液中Cu含量越高反而生物毒性越小。综上,模拟酸雨能促进不同粒径铅锌冶炼废渣中重金属离子的溶出释放、改变废渣中重金属的形态,并提高废渣浸出液的生物毒性,从而增大了铅锌冶炼废渣堆场的环境生态风险。     

利用发光菌评价17种染料的毒性效应

根据 1 995年国家标准规定的发光细菌法测定化合物的急性毒性标准 ,测定了 1 7种染料抑制发光细菌相对发光强度的 EC50 值。结果表明 ,碱性染料的毒性最大 ,还原性染料的毒性次之 ,酸性染料的毒性较小 ,活性染料和直接染料的毒性最小     

Ecotoxicity of Alternative De-icers

Background  De-icers are essential to wintertime road maintenance in Nordic countries. The use of road salts (NaCl, CaCl₂ and MgCl₂) is having significant effects on groundwater. There has been a growing concern of environmental effects resulting from de-icing. Regulatory bodies have tried to find de-icers which have less harmful impacts on soil and groundwater. Alternative new organic de-icers are e.g. potassium formiate, potassium acetate, and calcium magnesium acetate. Objectives  At present, the decision finding for soil and water quality assessment is mainly based on the results of chemical analyses. However, ecotoxicological characterization will provide more useful information for determining environmental effects of de-icers. Methods  Six different de-icers, NaCl, CaCl₂, MgCl₂, potassium formicate KFo, potassium acetate KAc and calcium magnesium acetate CMA were studied with different bioassays. These bioassays were two plant tests (onion Allium cepa root elongation test and duckweed Lemna growth inhibition test), an enzyme inhibition test (reverse electron transport test, RET) and a microbial test (luminescent bacteria Vibrio fischeri, BioTox test). Results and Discussion  Most of the responses of the de-icers tested were toxic to test organisms. CMA was unsuitable for RET and BioTox tests because it was not possible to analyze turbid samples with these bioassays. On the whole, organic chemicals were more toxic than the inorganic salts. According to the Lemna and Allium cepa tests KFo was the most toxic and the toxicity ranking of the de-icers was KFo > KAc > CMA > CaCl₂ > NaCl > MgCl_2. The sensitivity ranking for tests in decreasing order was Lemna > Allium cepa > RET > BioTox. The plant tests proved to be relevant, easy, cost-effective and sensitive screening methods of de-icers: Lemna test was 92 times more sensitive and Allium test 70 times more sensitive than BioTox to KFo. Conclusion and Outlook  The tested de-icers had significant effects on plant growth, microbial luminescence and enzymatic activity. Toxicity could hardly be predicted from the chemical concentrations of these de-icers. In summary, these results demonstrate a need for including toxicity measurements in the evaluation of technologies used in soil treatment and illustrate the potential value of such measurements for ensuring that no or minimal environmental contamination would arise from de-icing process.