摘要
微生物产生EPS受多种因素影响,其中重金属阳离子的作用较为明显,但其对应的阴离子的作用仍不明确.研究了SO;、NO;和Cl;对应的3种Cd(Ⅱ)化合物胁迫/诱导下Alcaligenes faecalis EPS的产量、组分变化及其吸附性能.结果表明,20 mg·L^(-1)Cd(NO_(3))_(2)的胁迫效果最为明显,EPS产量达到109.17 mg·g^(-1),其中蛋白质含量达到89.46 mg·g^(-1),较Control-EPS提高50%以上.在此条件下,Cd(NO_(3))_(2)-EPS对Cd(Ⅱ)吸附量最高,达到300.20 mg·g^(-1),较胁迫前增加41.83%.三维荧光(3D-EEM)、红外光谱(FTIR)和X射线光电子能谱(XPS)分析表明,胁迫后的EPS,尤其是Cd(NO_(3))_(2)-EPS中C=O、C-O/C-N含量增幅明显,在吸附Cd(Ⅱ)中发挥了重要作用.实验结果表明,在Cd(NO_(3))_(2)胁迫/诱导下,Alcaligenes faecalis可产生特异EPS,具有优异的吸附性能.本文为制备生物制剂以处理含重金属废水提供了重要理论指导.
Microbial production of extracellular polymeric substances(EPS)is affected by many factors,among which heavy metal cation plays an important role,but the role of the corresponding anions is still unclear.In this study,the effects of three Cd(II)compounds corresponding to SO;,NO;and Cl-on yield,composition and heavy metal adsorption performance of EPS from Alcaligenes faecalis were studied.The results showed that the most obvious stimulating effect was observed for 20 mg·L^(-1)Cd(NO_(3))_(2) with a EPS yield reached up to 109.17 mg·g^(-1),and the protein content reached 89.46 mg·g^(-1),which was more than 50% higher than that in Control-EPS.Under these conditions,the adsorption capacity of Cd(NO_(3))_(2)-EPS to Cd(Ⅱ)is the highest,reaching up to 300.20 mg·g^(-1),which is 41.83% higher than that produced in the absence Cd stress.Three-dimensional fluorescence(3D-EEM),infrared spectroscopy(FTIR)and X-ray photoelectron spectroscopy(XPS)analysis results showed that the EPS obtained under Cd stress,especially for Cd(NO_(3))_(2)-EPS,has a significant increase in C=O and C-O/C-N content which played an important role in the adsorption of Cd(II).The experimental results showed that under Cd(NO_(3))_(2) stress/induction,Alcaligenes faecalis can produce specific EPS with excellent adsorption capacity.This study provides important theoretical guidance for the preparation of biological agents to treat heavy metal-contaminated wastewaters.
作者
连泽阳
杨佐毅
宋卫锋
孙梦格
甘雨
陈舒棋
白晓燕
LIAN Zeyang;YANG Zuoyi;SONG Weifeng;SUN Mengge;GAN Yu;CHEN Shuqi;BAI Xiaoyan(School of Environmental Science and Engineering,Guangdong University of Technology,Guangzhou 510006)
出处
《环境科学学报》
CAS
CSCD
北大核心
2022年第4期81-90,共10页
Acta Scientiae Circumstantiae
基金
广东省自然科学基金(No.2021A1515010558)。
