低浓度TCEP对赤子爱胜蚓的氧化损伤及神经毒性的研究

 2022-01-18 12:01

论文总字数:21671字

目 录

1前言 6

1.1研究背景 6

1.2蚯蚓在毒性研究理论中的应用 6

1.3生物标志物中酶活性应用的简介 7

1.4研究目的及意义 8

2实验材料及方法 8

2.1实验材料 8

2.2实验仪器 8

2.3实验方法 8

2.3.1人工土壤配制 8

2.3.2蚯蚓的预处理 9

2.3.3染毒 9

2.3.4酶液的制取以及酶活性的测定 9

2.3.5蚯蚓体腔细胞提取 9

2.3.6蚯蚓体腔细胞彗星实验 10

3实验结果以及分析 10

3.1低浓度TCEP对抗氧化系统的影响 10

3.2低浓度TCEP作用下的氧化损伤产物的变化 12

3.3低浓度TCEP对乙酰胆碱酯酶活性的影响 14

3.4低浓度TCEP对蚯蚓的体腔细胞DNA损伤程度的影响 15

3.5结果分析 16

4结论与展望 17

4.1结论 17

4.2展望 17

参考文献 17

致谢 20

低浓度TCEP对赤子爱胜蚓的氧化损伤及神经毒性的研究

陈 晓 芳

,China)

Abstract: Tris(2-carboxyethyl)phosphine(TCEP) is a new type of organic phosphorus flame retardant, which is developed at present. With the rapid development of the domestic and international research level, TCEP of this kind of organic phosphate ester flame retardant (OPEs) was detected in a variety of environmental media, especially in soil and its biological. And soil as humans to survive an important capital materials, earthworms as the original ecology of the soil system important constituent part and groups of organisms in the largest category of biological, in soil ecosystem has the effect is very important, reflects the as contaminated soil can earthworms as a biological indicator, which is quite valid in scientific research work. This paper mainly uses artificial soil test, and Eisenia foetida as the object of study, its exposure in 0.1, 0.5, 1, 10 and 50 mg / kg of low concentration of TCEP artificial soil. The experiment lasted for 14 days. Mainly from two aspects of oxidative damage and neurotoxicity, the toxicity mechanism of TCEP to earthworms was studied and the preliminary analysis and evaluation were carried out. Main research results are: 1) Through the naked love wins earthworm antioxidant system indicators of catalase hydrogen peroxidase, catalase (CAT), glutathione (GSH) and activity of glutathione s - transferase (GST) activity measured results showed that under the effect of time and concentration of newborn baby love wins earthworm by relatively severe oxidative stress, so that the antioxidant system is relative damage. Oxidative damage determination of malonaldehyde (MDA) and 8-hydroxy deoxy guanosine (8-OHdG) results show that the maximum concentration of TCEP to 14 days, TCEP on earthworms have obvious oxidation effect. 2) In AChE activity was found, this experiment in relatively high concentration of TCEP, in the experiment to 14 days later, under the action of TCEP will the earthworms’ nervous system to ache the toxicity of key enzymes produced inhibitory effect, indicating that TCEP on the earthworms induced neurotoxic effects. 3)Detected by comet assay of earthworm DNA damage degree, with exposure to increasing concentrations of TCEP, earthworm coelomocyte OTM values and tail DNA% value has a significant upward trend, indicating that the increase of DNA damage and the concentration of TCEP and serious.

Key words: TCEP; Eisenia foetida;Oxidative Damage;Neurotoxicity;

1前言

三(2-氯乙基)磷酸酯(Tris(2-carboxyethyl)phosphine,TCEP),分子式是(ClCH2CH2O)3PO,分子量286g/mol,是一种无色的透明的新型含卤有机磷阻燃增塑剂。被广泛使用于塑料和涂料等制品中。还被使用于润滑油添加剂以及铀、钍和锝等稀有元素的抽提剂[1]。由于其在效果、使用以及价格方面均优于国内其他同类产品[2],因此在国内的使用量在逐步增多中。但是有关TCEP的毒性研究方面还处在初步研究的程度,因此单独的对TCEP对土壤生物进行毒性机理的研究也十分有意义。另一方面,TCEP作为OPEs有机物中典型的一类含卤代烷基磷酸酯,对于TCEP的研究有助于对OPEs的毒性效应进行全面的研究。

1.1研究背景

TCEP在其分子式中,同时含有磷(10.8%)、氯(36.7%)和酯键,是高分子材料中的优良的阻燃剂和增塑剂[3]。TCEP为无色澄清透明的液体,与一般正常的有机溶剂能相溶,并且不能溶于脂肪族烃类,水解时候稳定性优良,能够少量分解于氢氧化钠之中,沸点为194℃,热分解温度为240-280℃。

从属性上来说,TCEP属于OPEs有机物中典型的一类含卤代烷基磷酸酯。OPEs是应用最为广泛的有机磷类阻燃剂,就研究可知到目前为止已经普遍被发现存在于生物体[4-5]、水体[6-7]和大气中[8-9]。而经过研究表明,多种OPEs具有生殖毒性、神经毒性、致癌性和基因毒性等毒性,其环境危害也逐渐被发现[10-11]。由于OPEs具有持久性,虽然其环境介质中的相对浓度不足以明显的发生生物损害,但作为一类不易消除的有机类有毒污染物质的存在,是很有必要长期关注它在环境中的暴露存在情况的。因为OPEs也在土壤中持久残留,危害到土壤生态系统,也对其中的生物有毒害效应。因此近年来有关OPEs的研究越来越多。而TCEP也具有OPEs的某些性质,因此单独的对TCEP的研究也显得尤为重要。

结合相关的文献资料,TCEP所具有的相关性质有:1)TCEP能长期存在于环境介质中,TCEP在欧盟法规中达到了化学物质持久或者非常持久的筛选指标。研究表明,含氯的TCEP无法通过光降解[12-14]。2)TCEP在环境中尤其是土壤环境中浓度检出较低,但却普遍存在于沉积物和土壤中。3)TCEP容易在生物体内沉积,并且有放大趋势。因为具有卤素,在分解时会产生空气污染物卤代氢,以及致癌物等,而这些污染物也会长久蓄积在生物体内。

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