【作者】 赖金龙； 吴国； 陶宗娅； 罗学刚； 付倩； 张红；

【Author】 LAI Jin-long 1 , WU Guo 1 ,TAO Zong-ya 1* , LUO Xue-gang 2 ,FU qian 1 ,ZHANG Hong 1 (1.Life Science College, Sichuan Normal University, Chengdu 610101, China; 2. Engineering Research Center of Biomass Materials(SWUST),Ministry of Education), Mianyang 621010, China)

【机构】 四川师范大学生命科学学院； 生物质材料教育部工程研究中心(西南科技大学)；

【摘要】 邻苯二甲酸二丁酯(Dibutyl phthalate,DBP)主要作为增塑剂和软化剂广泛用于塑料制品的生产加工。随着塑料制品使用、废弃及焚烧,加工过程中并未与高分子碳链聚合的DBP可逐渐游离出来进入环境,已呈现明显的环境累积效应,成为农耕土壤中最常被检出的有机污染物之一。关于DBP环境生物学效应的研究分别从植物营养代谢、活性氧代谢、遗传毒理学等视角积累了一定的研究成果,但DBP对蚕豆的遗传毒性及其与活性氧代谢之间关系的报道很少。本研究以蚕豆为试材,采用溶液培养法,用含少量土温-80的配制液配制浓度(r)为、9mmol·L-1(T1)、18mmol·L-1(T2)、27mmol·L-1(T3)和36mmol·L-1(T4)的DBP处理液,处理组加入不同浓度DBP溶液,以配制液处理为对照(CK)分别培养24h、48h、72h。通过测试分析胚根蛋白质和脯氨酸含量、抗氧化酶活性及根尖细胞染色体结构变化,探讨DBP暴露对蚕豆的致毒效应及其与抗氧化酶活性变化之间的相互关系。结果显示:(1)DBP暴露条件下蚕豆胚根蛋白质和游离脯氨酸含量发生显著变化。处理组蛋白质含量均低于CK;24h时T2~T4处理的胚根脯氨酸含量显著高于CK17.35%~60.70%。(2)与CK比较,处理组胚根SOD活性高于CK,处理组POD活性随DBP浓度增加而递减CAT活性均显著低于CK14.00%~43.08%。结果表明,DBP暴露下蚕豆胚根SOD活性对保护细胞膜可能具有重要作用,POD和CAT均表现不同程度的敏感性。(3)DBP可诱导蚕豆根尖细胞发生相对较高的微核率,并具有一定的剂量-效应关系但不足以引起DNA片段化损伤。(4)本实验条件下,DBP对蚕豆的遗传毒性应为一种直接影响,但也存在活性氧代谢异常产生的过氧化损伤,脯氨酸含量显著增加可能对介导相关抗逆基因功能上调有积极意义。本研究初步阐明DBP对蚕豆胚根抗氧化酶活性的影响及遗传毒性效应,表明残留在农田生态系统中的DBP对农作物生长发育有一定的毒害作用。因此,在农用地膜尤其是环境可降解地膜加工过程中,应减少DBP及其同系物的使用量,以提高塑料制品尤其是农用地膜的环境安全性,减少对环境的污染。更多还原

【Abstract】 Di-n-butyl phthalate(DBP) served as plasticizer and softener was widely used in the production and processing of plastic products. As the plastics were extensively used, wasted and incinerated, DBP, which did not aggregated with polymer carbon chain during plastics processing, could gradually dissociated into the environment, and the accumulation effects of DBP shown obviously in environment. So DBP was the one of being detected commonly as the organic pollutants in farming system. There were more achievement about environmental and biological effects of DBP on the nutrient, metabolism of reactive oxygen species(ROS), genetic toxicity etc., but there was little known that genetic toxicity of DBP and the relationship with the ROS metabolism in broad bean(Vicia faba).In the study with the solution culture method, the germinated broad bean were treated with DBP solution for 24 h, 48 h and 72 h which the concentration were respectively 9mmol·L -1 (T1 ), 18 mmol·L -1 (T2 ), 27 mmol· L -1 (T 3 ), 36 mmol·L -1 (T4 ) and the control(CK) was 0 mmol·L -1 in which added a few of Tween-80. The contents of protein and proline, antioxidase activities and chromosome structures in the radicles were analyzed. The results showed that: (1) Treated with DBP, the contents of soluble protein and the free proline(Pro) significantly changed in the radicles. The protein contents in all treatments were reduced compared with CK, the proline contents were significantly increased (P<0.05) about 17.35%~60.70% treated with T2 ~T4 cultured for 24 h. (2) Compared with CK, in the radicle treated with DBP, SOD activities were higher, but POD activities were reduced as the concentration of DBP were increased, CAT activities were significantly lower than that of CK about 14.00%~43.08%. It’s obvious that SOD may play an important role in preserving the cell membrane, POD and CAT appeared the sensitivity to a certain degree. (3) The treatments with DBP could induce high frequency of micronuclear cells in the radicle and dosage effects presented, but not enough to result in DNA ladder. (4) It’s suggested that the genotoxicity of DBP may be an immediate roles and there were indirect effects of oxidative stress due to abnormal of ROS metabolism in broad bean. There may be positive impact that the proline concentration was increased significantly for the function up-regulation of related anti-stress genes. It’s concluded that the effects of DBP on antioxidase activities and genotoxicity in the radicles of broad bean were expounded in the study. The results indicated that there were certain toxic action of DBP infused into soil environment to the growth and development in crops. So it’s necessary that the usage of DBP and its homologue should be reduced during processing of agricultural film and degradable for the environmental safety更多还原