Shandong Key Laboratory of Water Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Shandong University, Qingdao, 266237, China.
Sino-French Research Institute for Ecology and Environment (ISFREE), School of Environmental Science and Engineering, Shandong University, Qingdao, 266237, China.
Environ Sci Pollut Res Int. 2022 Nov;29(55):82762-82771. doi: 10.1007/s11356-022-21299-3. Epub 2022 Jun 25.
Polyaspartic acid is considered a green agent for the treatment of circulating cooling water. However, its chemosynthetic process is not green, as it requires significant amounts of energy and causes water pollution. In this work, we identified an analog of polyaspartic acid, namely polyglutamic acid (γ-PGA), which could be directly produced by Bacillus spp., and we explored its performance and scale inhibition mechanism as a scale inhibitor. We found that γ-PGA secreted by B. megaterium with a molecular weight of ~ 70 kDa showed poor scale inhibition, while the γ-PGA secreted by B. licheniformis with a molecular weight of ~ 15 kDa had a 26.87% higher efficiency compared to commercially available polyaspartic acid. The scale inhibition mechanism was explored using the γ-PGA material secreted by B. licheniformis. Fourier transform spectrometer, field emission scanning electron microscopy, and X-ray photoelectron spectroscopy analysis demonstrated that the scale inhibition performance of γ-PGA was due to the combination of its functional groups and Ca, which affected the growth process of CaCO and inhibited the formation of CaCO. This study provided deeper insight into scale inhibition performance related to the scale inhibition mechanism.
聚天冬氨酸被认为是一种处理循环冷却水的绿色药剂。然而，其化学合成过程并不绿色，因为它需要大量的能源并造成水污染。在这项工作中，我们鉴定了聚天冬氨酸的类似物，即聚谷氨酸（γ-PGA），它可以由芽孢杆菌属直接产生，我们探索了其作为阻垢剂的性能和阻垢机制。我们发现，枯草芽孢杆菌分泌的分子量约为 70 kDa 的 γ-PGA 表现出较差的阻垢性能，而地衣芽孢杆菌分泌的分子量约为 15 kDa 的 γ-PGA 的效率比市售的聚天冬氨酸高 26.87%。我们使用地衣芽孢杆菌分泌的 γ-PGA 材料来探索阻垢机制。傅里叶变换光谱仪、场发射扫描电子显微镜和 X 射线光电子能谱分析表明，γ-PGA 的阻垢性能归因于其官能团与 Ca 的结合，这影响了 CaCO 的生长过程并抑制了 CaCO 的形成。这项研究为与阻垢机制相关的阻垢性能提供了更深入的了解。
