College of Environmental Science and Engineering, Guangdong University of Technology, Guangzhou, 510006, People's Republic of China.
Environmental Technology Center of Panyu District, Guangzhou, 511499, People's Republic of China.
Bioprocess Biosyst Eng. 2018 Jun;41(6):781-791. doi: 10.1007/s00449-018-1911-6. Epub 2018 Feb 17.
Bacillus vallismortis (B. vallismortis), an aerobic heterotrophic bacteria, was screened in a laboratory pilot study, to assess the interaction between the heavy metal Zn(II) and extracellular polymeric substances (EPS). The influence of Zn(II) stress on EPS production, component variation, and sorption performance, was investigated. The characteristics of B. vallismortis EPS formed under stress were analyzed using FTIR, 3D-EEM and XPS. EPS was used as an adsorbent and the adsorption capacity and adsorption behavior of EPS formed with and without Zn(II) stress, were compared and assessed. Results showed that the production of polysaccharides and proteins, the main components of EPS, were promoted under Zn(II) stress. The types of EPS functional groups observed remained the same with and without heavy metal stress, but their concentrations were increased. Due to stress-induction, the adsorption capacity of Zn-EPS was significantly enhanced compared with the control-EPS. Specific EPS produced by B. vallismortis in the presence of Zn(II) stress, could have a wide range of potential applications, allowing optimization and improvement of the capacity of EPS to remove heavy metals from effluent.
在实验室初步研究中筛选出了好氧异养细菌枯草芽孢杆菌（B. vallismortis），以评估重金属 Zn(II) 和细胞外聚合物（EPS）之间的相互作用。研究了 Zn(II) 胁迫对 EPS 产生、成分变化和吸附性能的影响。采用傅里叶变换红外光谱（FTIR）、三维荧光光谱（3D-EEM）和 X 射线光电子能谱（XPS）分析了应激下形成的 B. vallismortis EPS 的特性。将 EPS 用作吸附剂，比较和评估了有无 Zn(II) 胁迫下形成的 EPS 的吸附容量和吸附行为。结果表明，在 Zn(II) 胁迫下，EPS 的主要成分多糖和蛋白质的产量增加。有和没有重金属胁迫时，观察到的 EPS 功能基团类型相同，但浓度增加。由于胁迫诱导，Zn-EPS 的吸附容量与对照-EPS 相比显著增强。在 Zn(II) 存在下由 B. vallismortis 产生的特定 EPS，可能具有广泛的潜在应用，从而可以优化和提高 EPS 从废水中去除重金属的能力。
