Department of Water and Wastewater Engineering, School of Urban Construction, Wuhan University of Science and Technology, Wuhan, 430065, China.
Department of Chemical and Process Engineering, Faculty of Engineering and Built Environment, Universiti Kebangsaan Malaysia, 43600, UKM Bangi, Selangor, Malaysia; Research Centre for Sustainable Process Technology (CESPRO), Faculty of Engineering and Built Environment, Universiti Kebangsaan Malaysia, 43600, UKM Bangi, Selangor, Malaysia.
Environ Res. 2023 Dec 15;239(Pt 1):117244. doi: 10.1016/j.envres.2023.117244. Epub 2023 Sep 30.
Microalgal-bacterial granular sludge (MBGS) has attached attention for sustainable wastewater treatment, but it remains elusive whether it can adapt to outdoor light-limited conditions. This paper investigated the biological adaptation mechanisms of MBGS to outdoor light-limited diel conditions using real municipal wastewater. The results indicated that MBGS still had excellent pollutants removal performance, and that both the extracellular polymeric substances and glycogen content of MBGS increased significantly. The main functional microalgae and bacteria were revealed to be Leptolyngbyaceae and Rhodanobacteria, respectively. Further analyses indicated that the abundance of genes encoding PsbA, PsbD, PsbE, PsbJ, PsbP, Psb27, Psb28-2, PsaC, PsaE, PsaL, PsbX, PetB, PetA, and PetE increased in photosystem. Meanwhile, the abundance of gene encoding Rubisco decreased but the gene abundance regarding to crassulacean acid metabolism cycle increased. These suggested that MBGS could adjust the photosynthetic pathway to ensure the completion of photosynthesis. This study is anticipated to add fundamental insights for the MBGS process operated under outdoor light-limited conditions.
微藻-细菌颗粒污泥（MBGS）因其在可持续废水处理方面的应用而备受关注，但它是否能够适应户外光照受限的条件仍不清楚。本文使用实际的城市废水研究了 MBGS 对户外光照受限昼夜条件的生物适应机制。结果表明，MBGS 仍然具有优异的污染物去除性能，并且 MBGS 的胞外聚合物和糖原含量均显著增加。主要功能微藻和细菌分别被揭示为束丝藻科和红杆菌属。进一步的分析表明，编码 PsbA、PsbD、PsbE、PsbJ、PsbP、Psb27、Psb28-2、PsaC、PsaE、PsaL、PsbX、PetB、PetA 和 PetE 的基因的丰度在光合作用系统中增加。同时，编码 Rubisco 的基因丰度降低，但与景天酸代谢循环有关的基因丰度增加。这表明 MBGS 可以调整光合作用途径以确保光合作用的完成。本研究为户外光照受限条件下的 MBGS 工艺运行提供了基础见解。
