磺胺甲恶唑在沉积物中的降解行为研究

为评价磺胺类抗生素在沉积物中降解行为,以最常用的磺胺类药物——磺胺甲恶唑(SMZ)为对象,通过不同的环境条件下室内模拟实验,研究了其在沉积物中的降解动态以及相关环境因素(微生物、含氧量、光照、沉积物种类和药物起始浓度等)对降解过程的影响情况。结果表明,SMZ在沉积物中的降解途径主要为兼性厌氧微生物降解,非生物降解等其他降解途径只占较小比例。SMZ的降解速率与沉积物的有机质含量密切相关,高有机质含量的沉积物中SMZ的降解更快,沉积物中的光敏剂也能促进SMZ的降解。高浓度的SMZ通过抑制沉积物微生物的活性,使得其降解显著下降。

Degradation of Sulfamethoxazole in Sediments

Antibiotics in the environment have drawn much concern recently by both scientific and regulatory communities,mainly due to their spread and maintenance of bacterial resistance.To investigate the environmental fate and transport of antibiotics in aquatic system is thus necessary for their risk assessment and pollution control.Sulfamethoxazole(SMZ) was one of the most routinely used sulfonamides antibiotics,which was widely found in the environment.In this study,a series of experiment were conducted to determine the effect of variables including initial SMZ concentration,different redox condition,sediments with different properties,microorganism and light on SMZ degradation in sediments.The results showed that the SMZ degradation in sediments was mainly attributed to the facultative anaerobes degradation,while abiotic degradation played a minor role.SMZ degradation in the sediment with high organic matter content was faster than in the sediment with low organic matter content,probably due to the higher microorganism density thereby microorganism activity caused by high organic matter.Other environmental factors such as the inorganic photosensitizer in sediment may also accelerate the degradation of SMZ through photocatalytic reactions.SMZ degradation was inhibited at high initial SMZ concentration,probably due to the inhibition of microorganism activities by high SMZ levels.