蒽和苯并芘单独及联合作用对三叶浮萍的生态毒理学效应

发布时间：2018-05-18 14:53

本文选题：蒽 + 苯并芘　；参考：《曲阜师范大学》2015年硕士论文

【摘要】：随着社会的进步,现代工业的发展,人们的生活水平不断提高,环境污染也越来越严重,备受人们关注的环境问题就是水体污染。我国淡水资源分布不均匀,而且淡水总量占水资源总量的比例还不到百分之一。未经处理或者处理不达标的工业废水直接排放到河流当中,其中含有大量的有毒有害物质,直接污染水体,使水体质量急剧下降,水生生物的生存受到威胁,进而威胁人体健康。生活污水的排放量也日趋增多,其中含有大量的有机化合物,也会对水体造成污染,使其富营养化。多环芳烃(polycyclic aromatic hydrocarbons,PAHs)是水体环境中普遍存在的有机污染物,工业废水中含有大量的PAHs,目前发现的200多种PAHs,其中相当一部分都具有强致癌性和致突变性,毒性最强的就是苯并芘和蒽。蒽和苯并芘作为很多PAHs的母体,探讨二者单独及联合作用下对淡水植物的毒性作用,可为研究其它PAHs对淡水生物的生态毒理效应提供有力的证据。三叶浮萍(Lemna minor),又叫浮萍或青萍,是淡水中极易常见的漂浮植物,在淡水植物中生长有着绝对的优势,其叶片漂浮水面,根深入水中吸收营养物质,生长速度快,繁殖速率高。作为淡水生态系统的初级生产者,利用水中营养成分作为碳源,通过光合作用贮存能量,通过生物富集作用可影响其它淡水生物,在净化水体,指示水体质量中起到十分关键的作用。本文以浮萍为受试对象,通过生态毒理实验,研究了多环芳烃(PAHs)——蒽(Anthracene)和苯并[α]芘(Bap)单独及联合作用对浮萍从种群到个体再到细胞进而到分子水平的毒性影响,得到了一些有价值的结果:1、蒽对浮萍生理生化指标的影响。(1)蒽对浮萍的生长有抑制作用,而且呈现出了十分明显的剂量效应关系,即随着蒽浓度的不断升高,浮萍的相对增长率不断下降。(2)随着蒽浓度升高,叶绿素含量呈现先升高后降低;丙二醛(MDA)含量呈现升高的趋势;过氧化物酶(POD)活性先升高后降低。2、苯并芘对浮萍生理生化指标的影响。(1)苯并芘对浮萍的生长总体呈现抑制效应,但是当苯并芘浓度低于0.5mg/L时,对浮萍的生长呈现促进的趋势,当苯并芘浓度高于0.5mg/L时,对浮萍生长呈现抑制的趋势,其相对增长率不断下降。(2)随着苯并芘浓度的升高,叶绿素含量呈现降低的趋势;丙二醛(MDA)含量呈现先升高后降低;过氧化物酶(POD)活性变化不大,但总体呈下降趋势。3、蒽和苯并芘联合作用下对浮萍生理生化指标的影响。(1)蒽和苯并芘联合作用下,毒性加强,对浮萍生长呈现十分明显的抑制效应,且作用效果分别强于单一效果,表现为协同作用。(2)将苯并芘浓度固定0.5mg/L,随着蒽浓度的升高,其相对增长率下降;叶绿素含量不断降低;丙二醛(MDA)含量有所增高,但幅度不大;过氧化物酶(POD)活性急剧下降。4、蒽和苯并芘联合作用下对浮萍DNA损伤的影响。(1)丙酮处理下的浮萍DNA电泳图与对照组没有明显区别。(2)浓度为0.5mg/L的苯并芘分别于浓度为5mg/L和20mg/L的蒽复合作用下,与对照相比,条带逐渐模糊,DNA受损程度逐渐加重,含量降低。5、蒽和苯并芘联合作用下对浮萍亚显微结构的变化影响。(1)丙酮处理下的浮萍亚显微结构与对照组无明显差异,均保持正常状态。(2)蒽单一作用下随浓度升高,细胞受损逐渐严重,亚显微结构发生变化。(3)联合作用下与相同浓度的蒽对比,对细胞损伤更加严重,细胞内部结构严重变形,甚至出现叶绿体溶解,质壁分离严重,内部结构紊乱。
[Abstract]:With the progress of society and the development of modern industry, the living standard of people is increasing and environmental pollution is becoming more and more serious. The environmental problem which has attracted people's attention is water pollution. The distribution of fresh water resources in China is uneven, and the proportion of the total amount of fresh water in the total amount of water resources is less than one percent. Industrial wastewater is directly discharged into the river, which contains a large number of toxic and harmful substances, which directly pollute the water body, make the quality of water decline sharply, the survival of aquatic organisms are threatened, and then threaten the health of the human body. The discharge of domestic sewage is also increasing, which contains a large amount of organic compounds, which will also cause pollution to the water body. Eutrophication. Polycyclic aromatic hydrocarbons (polycyclic aromatic hydrocarbons, PAHs) are common organic pollutants in the water environment. There are a large number of PAHs in industrial waste water. More than 200 kinds of PAHs have been found at present. Some of them have strong carcinogenicity and mutagenicity, and the most toxic are a lot of benzopyrene and anthracene and benzopyrene. The maternal body of PAHs, which explores the toxic effects of two individual and combined effects on freshwater plants, provides powerful evidence for the study of the ecological toxicological effects of other PAHs on freshwater organisms. The Lemna minor, also called duckweed or Azolla, is a very common floating plant in fresh water and has an absolute advantage in the growth of freshwater plants. As the primary producer of the freshwater ecosystem, the nutrient components of the freshwater ecosystem are used as the carbon source, and the energy of the photosynthesis can be used to store the energy, and the biological enrichment can affect the other freshwater organisms, and the water purification can be used as a indicator of the water quality. In this paper, the toxic effects of polycyclic aromatic hydrocarbons (PAHs) - anthracene (Anthracene) and benzo [alpha] pyrene (Bap) on the toxicity of duckweed from population to individual to cell to molecular level were studied by the ecological toxicology experiment, and some valuable results were obtained: 1, anthracene to the physiology and biochemistry of duckweed. (1) anthracene had a inhibitory effect on the growth of duckweed, and showed a very obvious dose effect relationship, that is, the relative growth rate of duckweed decreased with the increase of anthracene concentration. (2) the content of chlorophyll increased first and then decreased with the increase of anthracene concentration; the content of malondialdehyde (MDA) increased. The enzyme (POD) activity first increased and then decreased.2, the effect of benzopyrene on the physiological and biochemical indexes of duckweed. (1) benzopyrene had an overall inhibition effect on the growth of duckweed, but when the concentration of benzopyrene was lower than 0.5mg/L, the growth of duckweed was promoted. When the concentration of benzopyrene was higher than 0.5mg/L, it showed a tendency to inhibit the growth of duckweed. The growth rate declined continuously. (2) with the increase of the concentration of benzopyrene, the chlorophyll content showed a decreasing trend; the content of malondialdehyde (MDA) increased first and then decreased; the activity of peroxidase (POD) changed little, but the overall decrease trend was.3, and the effect of anthracene and benzopyrene on the physiological and biochemical indexes of duckweed. (1) anthracene and benzopyrene co operation Under use, the toxicity was strengthened, and the growth of duckweed was obviously inhibited, and the effect was stronger than the single effect. (2) the concentration of benzopyrene was fixed for 0.5mg/L. With the increase of anthracene concentration, the relative growth rate decreased; the content of chlorophyll was decreasing; the content of malondialdehyde (MDA) was increased, but the amplitude was not large; The effects of chemical enzyme (POD) activity on.4, anthracene and benzopyrene on the DNA damage of duckweed. (1) the DNA electrophoresis diagram of duckweed under acetone treatment was not significantly different from that of the control group. (2) a benzopyrene with a concentration of 0.5mg/L was applied to the anthracene with a concentration of 5mg/L and 20mg/L respectively. Compared with the control, the strip was gradually blurred and the degree of DNA damaged. The changes in the submicroscopic structure of duckweed under combined effect of.5, anthracene and benzopyrene were gradually aggravated. (1) the submicroscopic structure of duckweed under acetone treatment was not significantly different from that of the control group. (2) the cell damage was gradually serious and the submicroscopic structure changed with the concentration of anthracene under the single action. (3) joint action. Compared with the same concentration of anthracene, the cell damage is more serious, the internal structure of the cell is seriously deformed, even the chloroplast dissolves, the separation of the mass wall is serious and the internal structure is disorganized.
【学位授予单位】：曲阜师范大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：X171.5

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