摘要
由北京某污水处理厂活性污泥中分离出以17α-乙炔基雌二醇(EE2)为唯一碳源生长的单一菌株,经16SrRNA基因序列分析鉴定为香茅醇假单胞菌(Pseudomonas citronellolis),命名为SS-2菌株.研究表明,SS-2菌株在7d内对初始浓度为4mg·L-1EE2的降解率为93.6%,对初始浓度为2mg·L-1雌酮(E1)、或17β-雌二醇(E2)的降解率为99%,对雌三醇(E3)没有降解能力.SS-2菌株降解雌激素的反应符合动力学一级反应定律,其降解速率常数分别为0.236h-1(E1)、0.221h-1(E2)和0.013h-1(EE2).SS-2菌株降解E2的过程中,检测到E1的生成,并且生成的E1亦可被SS-2菌株降解;该降解过程中类雌激素活性随着E2与E1浓度的降低而显著减少,表明SS-2菌株不仅可以降解E2与E1,而且可以降低降解过程中的类雌激素活性;反应进行240h后,仍表现出少量类雌激素活性,推测是因残留的E2或E1所致,表明尚且未知的中间产物或生成物的类雌激素活性远低于E2与E1.
A 17α-ethynylestradiol（EE2） degrading microorganism was isolated from activated sludge of a wastewater treatment plant in Beijing,China.16S rRNA gene sequence analysis was conducted,and this strain was identified as Pseudomonas citronellolis and designated as strain SS-2.It degraded 93.6% of EE2 at an initial concentration of 4 mg·L-1 in seven days,with a first-order rate constant of 0.013 h-1.It degraded 99% of estrone（E1） and 17β-estradiol（E2） at an initial concentration of 2 mg·L-1 in 1.5 days,with a first-order rate constant of 0.236 h-1 for E1 and 0.221 h-1 for E2.In the degradation process of E2 by strain SS-2,E1 was produced and further degraded by strain SS-2.Yeast two-hybrid assays showed that the estrogenic activity significantly decreased during degradation of E2 by strain SS-2,and strain SS-2 not only degraded E2 and E1,but also reduced the estrogenic activity generated from E2,E1 or their degradation intermediates and products.Moreover,after 240h degradation by strain SS-2 at an initial concentration of 2 mg·L-1,the E2 samples used here still showed weak estrogenic activity.The results indicated that the weak estrogenic activity was caused by the residual E2 or E1.The result suggests that the estrogenic activity of unknown intermediate（s） or products were far lower than those of E2 or E1.
出处
《环境科学学报》
CAS
CSCD
北大核心
2010年第12期2414-2419,共6页
Acta Scientiae Circumstantiae
基金
国家自然科学基金项目(No.20877009)
北京市自然科学基金项目(No.8093034)~~
