Cadmium adsorption on bacteria–mineral mixtures: effect of naturally occurring ligands
Cadmium adsorption on bacteria–mineral mixtures: effect of naturally occurring ligands
复制标题
DOI：
10.1111/ejss.12373
复制
发表时间：
2016-09
影响因子：
4.2
通讯作者：
H. Du;Wenli Chen;P. Cai;X. Rong;Chengrong Chen;Qiaoyun Huang
中科院分区：
文献类型：
--
作者：
H. Du;Wenli Chen;P. Cai;X. Rong;Chengrong Chen;Qiaoyun Huang
重金属在土壤中的迁移和归宿强烈地依赖于它们与天然存在的配体和吸附剂如细菌-矿物复合物的相互作用，这些配体和吸附剂是土壤中最重要的生物活性组分之一。然而，各种配体影响细菌-矿物复合物吸附重金属的机制仍不清楚。在这项研究中，几个无机和有机配体对镉吸附假单胞菌putida蒙脱石（蒙特）和假单胞菌putida针铁矿混合物的影响进行了研究与宏观吸附的测量。结果表明，柠檬酸盐和胡敏酸对恶臭假单胞菌和恶臭假单胞菌针铁矿吸附Cd有促进作用。相反，草酸抑制镉吸附。磷酸盐表现出有限的和增加的镉吸附，这取决于混合物的类型。恶臭假单胞菌-针铁矿对镉的吸附量增加，而恶臭假单胞菌-Mont对镉的吸附量减少。这项研究提供了第一个令人信服的证据，表明配体对细菌-矿物混合物的影响不能简单地从对这种混合物的单个组分的影响中推断出来。正、中性或负效应还取决于配体的类型和浓度以及形成细菌-矿物混合物的矿物种类。
The mobility and fate of heavy metals in soil depend strongly on their interactions with naturally occurring ligands and sorbents such as bacteria–mineral complexes, which are among the most important bioactive components in soil. However, the mechanism through which the various ligands affect heavy metal adsorption on bacteria–mineral complexes remains unclear. In this study, the effects of several inorganic and organic ligands on Cd adsorption on Pseudomonas putida–montmorillonite (Mont) and Pseudomonas putida–goethite mixtures were examined with measurements of macroscopic sorption. The results showed that citrate and humic acid enhanced Cd adsorption on P. putida–Mont and P. putida–goethite. Conversely, oxalate suppressed Cd adsorption. Phosphate showed both limited and increased Cd adsorption, depending on the types of mixture. Cadmium adsorption was increased on P. putida–goethite, but was reduced on P. putida–Mont. This study provided the first compelling evidence that the effects of ligands on bacteria–mineral mixtures cannot simply be inferred from the effects on the individual components of such mixtures. The positive, neutral or negative effects also depend on the types and concentrations of ligands as well as the mineral species that form the bacteria–mineral mixtures.