Song Xueting, Kong Fanying, Liu Bing-Feng, Song Qingqing, Ren Nan-Qi, Ren Hong-Yu
State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, 73 Huanghe Road, Harbin 150090, China.
School of Water Conservancy and Civil Engineering, Northeast Agricultural University, Harbin 150030, China.
Water Res. 2024 Mar 1;251:121120. doi: 10.1016/j.watres.2024.121120. Epub 2024 Jan 8.
Waste activated sludge (WAS) as one of the major pollutants with a significant annual production, has garnered significant attention regarding its treatment and utilization. If improperly discharged, it not only caused environmental pollution but also led to the wastage of valuable resources. In this study, the microalgae growth and lipid accumulation using waste activated sludge extracts (WASE) under different temperature conditions were investigated. The highest lipid content (59.13%) and lipid productivity (80.41 mg L d) were obtained at cultivation temperatures of 10 and 25 °C, respectively. It was found that microalgae can effectively utilize TN/TP/NH-N and other nutrients of WASE. The highest utilization rates of TP, TN and NH-N were achieved at a cultivation temperature of 10 °C, reaching 84.97, 77.49 and 92.32%, respectively. The algal fatty acids had carbon chains predominantly ranging from C14 to C18, making them suitable for biodiesel production. Additionally, a comprehensive analysis of transcriptomics and metabolomics revealed up-regulation of genes associated with triglyceride assembly, the antioxidant system of algal cells, and cellular autophagy, as well as the accumulation of metabolites related to the tricarboxylic acid (TCA) cycle and lipids. This study offers novel insights into the microscopic mechanisms of microalgae culture using WASE and approaches for the resource utilization of sludge.
剩余活性污泥（WAS）作为年产量巨大的主要污染物之一，其处理与利用已受到广泛关注。若排放不当，不仅会造成环境污染，还会导致宝贵资源的浪费。本研究考察了在不同温度条件下利用剩余活性污泥提取物（WASE）培养微藻及脂质积累情况。在培养温度分别为10℃和25℃时，脂质含量最高（59.13%），脂质生产率最高（80.41 mg L⁻¹ d⁻¹）。研究发现，微藻能够有效利用WASE中的TN/TP/NH₃-N等营养物质。在培养温度为10℃时，TP、TN和NH₃-N的利用率最高，分别达到84.97%、77.49%和92.32%。藻类脂肪酸的碳链主要在C14至C18之间，适合用于生物柴油生产。此外，转录组学和代谢组学的综合分析表明，与甘油三酯组装、藻类细胞抗氧化系统和细胞自噬相关的基因上调，以及与三羧酸（TCA）循环和脂质相关的代谢物积累。本研究为利用WASE培养微藻的微观机制及污泥资源利用途径提供了新见解。
