摘要
考察了嗜麦芽窄食单胞菌(Stenotrophomonas maltophilia)对芘的降解及对镉(Cd)的吸附,并初步探讨了其修复芘、Cd单一污染和复合污染的机理。结果表明,随着芘浓度的升高,S.maltophilia对芘的降解率先上升后下降,在浓度为2mg·L-1时,降解率最高,经4d达到65.74%。复合污染情况下,低浓度Cd(浓度小于0.5mg·L-1)对菌降解芘没有显著的影响,当Cd浓度为5、10mg·L-1时,则会抑制S.maltophilia降解芘,且不利于Cd的去除。扫描电镜(SEM)结果显示,S.maltophilia在各污染体系中基本能保持完整形态,芘、Cd复合污染体系对菌体毒性作用最强,可导致菌体表面凹陷,少量菌体出现胀破现象。傅里叶变换红外光谱(FTIR)分析表明,随时间延长以及降解/吸附,芘-Cd会对S.maltophilia细胞表面基团产生影响。
The characteristics of pyrene degradation and Cd adsorption by Stenotrophomonas maltophilia were investigated and the mechanisms of repairing the single pollution of pyrene,Cd and the co-contamination of these two by the strain were preliminarily studied.The results showed that the degradation efficiency of pyrene firstly ascended and then descended with the increase of pyrene concentration.The highest degradation ratio of 65.74% was reached when pyrene concentration came up to 2 mg·L-1 after 4 d.Under the circumstance of pyrene-Cd combined contamination,low concentration of Cd（less than 0.5 mg·L-1）played no significant influence on the degradation of pyrene,while high concentrations of Cd（5 mg·L-1 and 10 mg·L-1）inhibited pyrene degradation and was detrimental to Cd removal.The SEM observation indicated that S.maltophilia could maintain integral shape in either pollution system,while the combined pyrene-Cd exhibited the worst toxicity on the cell since it caused local depression on cell surface and some cells busted.FTIR analysis showed that with increasing time as well as the degradation/adsorption of pyrene-Cd some changes were made on the cell surface groups.
出处
《农业环境科学学报》
CAS
CSCD
北大核心
2013年第3期629-634,共6页
Journal of Agro-Environment Science
基金
国家自然科学基金委-广东省联合基金重点项目(U0933002)
国家自然科学基金项目(50978122)
广州市科技局科技计划项目(2011J4300075)
关键词
芘
CD
复合污染
嗜麦芽窄食单胞菌
pyrene
cadmium
combined contamination
Stenotrophomonas maltophilia
