Enzymatic treatment of estrogens and estrogen glucuronide

Natural and synthetic estrogens from sewage treatment systems are suspected to influence the reproductive health of the animals in the rivers.In this article we investigated the enzymatic treatment of three estrogens (estrone,17β-estradiol,and 17α-ethynyletstradiol) by a fungal laccase which oxidize phenolic compounds with dissolved oxygen.The elimination of the estrogenic activities by enzymatic oxidation was demonstrated by medaka vitellogenin assay.In addition,we developed an enzymatic treatment system comprised of β-D-glucuronidase and the laccase for 17β-estradiol 3-(β-D-glucuronide) degradation.The two enzymes eliminated 17β-estradiol 3-(β-D-glucuronide) and the intermediate,17β-estradiol,efficiently.     

炔雌醇和壬基酚在土壤中的吸附-解吸特征

通过吸附动力学研究和批量平衡试验,以炔雌醇(EE2)和壬基酚(NP)为代表,考察内分泌干扰物在3种不同性质的天然土壤中的吸附-解吸特征.结果表明,双室一级动力学模型比单室一级动力学模型更适合描述EE2、NP在土壤中的动态吸附过程.快吸附过程在吸附初期占据主导地位,之后慢吸附室的相对贡献逐渐增大,直至达到吸附平衡.土壤对NP的吸附速率是EE2的2.0～4.7倍.Freundlich模型和DA模型均能较好地拟合EE2与NP的吸附等温线,但DA模型拟合效果更佳.饱和吸附容量与土壤有机质含量呈显著正相关,EE2的饱和吸附容量(0.85～7.67μg·g-1)明显低于NP(10.47～110.15μg·g-1).吸附自由能计算表明,土壤对EE2和NP的吸附以物理作用为主.此外,3种受试土壤对EE2和NP的解吸附均存在滞后现象,需要预防其潜在的环境风险,其中有机质含量最高、比表面积最大的土样滞后性最明显.