典型磺胺类抗生素对土壤脱氢酶和过氧化氢酶活性的影响

Impact of the typical sulfonamides on the enzyme activities of the soil

随着磺胺类抗生素(Sulfonamides)的大规模生产和使用,其对环境的危害日益加重。通过试验室盆栽试验的方法,研究了3种典型磺胺类抗生素磺胺甲恶唑(SMZ)、磺胺甲基嘧啶(SM1)、磺胺噻唑(ST),在不同染毒剂量下,单一与两两复合污染对油菜种植土壤脱氢酶(DHA)和过氧化氢酶(CAT)活性的影响。结果表明,SMZ和SM1均对DHA活性产生抑制作用,而ST对DHA的活性呈现诱导作用,并且随着染毒质量比的增加,作用效应均呈增强趋势。SM1与ST对CAT活性产生诱导作用,同时随染毒质量比增加,诱导作用明显减弱。而SMZ对CAT的活性呈抑制作用,低质量比时,这种抑制作用不显著(p<0.05),高质量比时,SMZ对CAT的活性产生极显著(p<0.01)抑制作用。复合组并未显著增强对DHA和CAT的毒性效应,复合污染对土壤酶活性的效应与染毒质量比及土壤酶的种类等均相关。由以上可见,用土壤酶活性指标来表征土壤磺胺类抗生素污染情况是可行的。

The main purpose of this paper is to discuss the ecotoxical impact of sulfamethoxazole(SMZ),sulfamerazine(SM1),and sulfathiazole(ST) on the soil environment.For this purpose,we have done a series of pot-growing experiments with 2 content concentration rates(15 mg/kg and 45 mg/kg) of the typical sulfonamides under the single and joint pollution modes.The plant under our testing study has been chosen in this paper is known as rape(Brassica campestris),which has been widely distributed all over the country.The results of our study and analysis indicate that all of the three sulfonamides tend to have a significant inhibiting(p < 0.01) effect on the DHA activity in the rape planted soil,though in small amounts,say,15 mg/kg of SMZ,which may fail to bring any significant change(p > 0.05) on the DHA activity.Nevertheless,45 mg/kg SMZ would be great enough to bring significant inhibiting impact on the DHA activity.With both low and high concentrations,all the joint treatments can significantly(p < 0.05) induce the CAT activity in the rape planted soil,except through the 45 mg/kg SMZ + SM1 treatment.What is more,as compared to the single toxicity of SAs,the joint toxicity of them may not tend to increase.This may account for the effect of the combined pollution of SAs on the soil enzyme activities,which is dependent on the concentration combinations and enzyme types.Thus,it can be seen that the research method and results imply that the changes of enzyme activities should be taken as a biochemical indicator of sulfonamide pollution affecting the soil environment in the form of eco-toxicity.