Regulatory effects of signal molecules on microorganisms in bulking sludge at low temperatures

doi:10.16085/j.issn.1000-6613.2025-0392

Abstract

Abstract:

Currently, wastewater treatment plants in low temperature areas are still facing the risk and dilemma of sludge bulking. In this study, three SBR were operated at 8℃ with exogenous addition of 40μg/L of C4-HSL, C6-HSL and C8-HSL, respectively, and the original bulking sludge of the wastewater treatment plants was used as a control to investigate the effects of quorum sensing (QS) mediated by signal molecules on the sludge settling performance, EPS secretion, microbial activity, and microbial community composition under low temperature. The results indicated that for the sludge that had already undergone sludge bulking at low temperatures, compared with C6-HSL and C8-HSL, C4-HSL-mediated QS exhibited a more significant inhibitory effect on sludge bulking. After 42 cycles of operation, the SVI of the C4-HSL, C6-HSL and C8-HSL groups decreased by 38.19%, 30.90% and 33.68%, respectively. Exogenous C4-HSL increased the EPS content in favor of microorganisms below the unfavorable effects of low temperature and enhanced sludge settling performance. In addition, the QS mediated by C4-HSL could promote bacterial energy synthesis, which increased microbial activity in varying degrees. At 8℃, C4-HSL reduced the abundance of bacteria that caused sludge bulking while elevated the abundance of functional bacterial genera, and significantly changed the community structure, thus effectively controlling sludge bulking. The results indicated that C4-HSL-mediated QS was a promising wastewater treatment technology, which was of positive and important practical significance for improving the sludge traits and enhancing the wastewater treatment effect and load of wastewater treatment plants in low temperature areas.

Key words: quorum sensing, signal molecules, N-acyl homoserine lactone, sludge bulking, low temperature

摘要：

目前低温地区污水处理厂仍面临着污泥膨胀高发的风险和困境。本文在8℃下运行3个序批间歇式反应器（SBR），分别外源添加40μg/L的N-丁酰基-L-高丝氨酸内酯（C4-HSL）、己酰-L-高丝氨酸内酯（C6-HSL）和辛酰基-L-高丝氨酸内酯（C8-HSL），并以污水处理厂原始膨胀污泥作为对照，研究信号分子所介导的群体感应（quorum sensing，QS）对低温环境下污泥沉降性能、胞外聚合物（EPS）分泌、微生物活性以及微生物群落组成的影响。结果表明，对于低温下已经发生丝状菌膨胀的污泥，与C6-HSL和C8-HSL相比，C4-HSL所介导的QS对污泥膨胀和丝状菌表现出更明显的抑制作用。经过42个周期运行后，C4-HSL、C6-HSL和C8-HSL组的污泥体积指数（SVI）分别降低了38.19%、30.90%和33.68%。外源C4-HSL提高了EPS含量，有利于微生物抵御低温环境的不利影响，增强污泥沉降性能。此外，C4-HSL所介导的QS可以促进细菌能量合成，不同程度上增加了微生物活性。在8℃条件下，外源投加C4-HSL降低了与污泥膨胀相关的菌门相对丰度，提升功能菌属丰度，显著改变群落结构，从而有效控制污泥膨胀。结果表明，C4-HSL介导的QS是一种前景广阔的废水处理技术，对改善低温地区污水处理厂污泥性状、提升污水处理效果及负荷具有积极重要的现实意义。

关键词: 群体感应, 信号分子, N-酰基高丝氨酸内酯, 污泥膨胀, 低温

CLC Number:

X703.1

FENG Zhihua, ZHU Baibin, LIU Xizhong, DONG Xiaoqing, WANG Tao, YAN Yuchen, YUAN Fan, LIU Yiran, CHEN Ying. Regulatory effects of signal molecules on microorganisms in bulking sludge at low temperatures[J]. Chemical Industry and Engineering Progress, 2025, 44(S1): 559-566.

冯志华, 朱柏宾, 刘希忠, 董小庆, 王涛, 颜宇辰, 袁凡, 刘怡然, 陈滢. 信号分子对低温膨胀污泥中微生物的调控作用[J]. 化工进展, 2025, 44(S1): 559-566.

Figures/Tables 6

References 34

[1]	WANG Juan, LI Qian, QI Rong, et al. Sludge bulking impact on relevant bacterial populations in a full-scale municipal wastewater treatment plant[J]. Process Biochemistry, 2014, 49(12): 2258-2265.
[2]	张培胜, 李轶, 王龙飞. 我国高原污水处理厂现存问题及其展望[J]. 环境工程, 2019, 37(5): 82-86, 91.
	ZHANG Peisheng, LI Yi, WANG Longfei. Brief discussion on existing problems and prospects of plateau wastewater treatment plants in China[J]. Environmental Engineering, 2019, 37(5): 82-86, 91.
[3]	费学宁, 张旭阳, 王乐, 等. 温度对污泥膨胀的贡献关系及丝状菌演替规律[J]. 工业水处理, 2021, 41(6): 192-196.
	FEI Xuening, ZHANG Xuyang, WANG Le, et al. Contribution of temperature to sludge bulking and the rule of filamentous bacteria succession[J]. Industrial Water Treatment, 2021, 41(6): 192-196.
[4]	高春娣, 张娜, 韩徽, 等. 低温下丝状菌膨胀污泥的微生物多样性[J]. 环境科学, 2020, 41(7): 3373-3383.
	GAO Chundi, ZHANG Na, HAN Hui, et al. Microbial diversity of filamentous sludge bulking at low temperature[J]. Environmental Science, 2020, 41(7): 3373-3383.
[5]	王贺, 周瑜, 李秀芬, 等. 温度对浸没式MBR运行及污泥性质的影响[J]. 水处理技术, 2018, 44(10): 66-70.
	WANG He, ZHOU Yu, LI Xiufen, et al. Effect of operating temperature on submerged MBR operation and sludge properties[J]. Technology of Water Treatment, 2018, 44(10): 66-70.
[6]	GUO Jingbo, ZHANG Lanhe, CHEN Wei, et al. The regulation and control strategies of a sequencing batch reactor for simultaneous nitrification and denitrification at different temperatures[J]. Bioresource Technology, 2013, 133: 59-67.
[7]	NI Qianhan, CHEN Ying, LU Lanxin, et al. C4-HSL-mediated quorum sensing regulates nitrogen removal in activated sludge process at low temperatures[J]. Environmental Research, 2024, 244: 117928.
[8]	FENG Huajun, DING Yangcheng, WANG Meizhen, et al. Where are signal molecules likely to be located in anaerobic granular sludge?[J]. Water Research, 2014, 50: 1-9.
[9]	YONG Yangchun, WU Xiangyang, SUN Jianzhong, et al. Engineering quorum sensing signaling of Pseudomonas for enhanced wastewater treatment and electricity harvest: A review[J]. Chemosphere, 2015, 140: 18-25.
[10]	MANEFIELD Mike, WHITELEY Andrew S. Acylated homoserine lactones in the environment: Chameleons of bioactivity[J]. Philosophical Transactions of the Royal Society of London Series B, Biological Sciences, 2007, 362(1483): 1235-1240.
[11]	LI Wenbo, ZHANG Xiao, ZHAO Bowei, et al. Advancing the treatment of low carbon-to-nitrogen ratio municipal wastewater using a novel microaerobic sludge bed approach: Insights into enhanced performance and functional microbial community[J]. Environmental Research, 2024, 258: 119461.
[12]	American Public Health Association. Standard methods for the examination of water and wastewater[R]. 21st Ed.Washington DC: American Public Health Association, 2012.
[13]	WANG Weigang, YAN Yuan, ZHAO Yuhao, et al. Characterization of stratified EPS and their role in the initial adhesion of anammox consortia[J]. Water Research, 2020, 169: 115223.
[14]	YUAN C J, LIU M, DU Y, et al. Comparison of the effect of pre-ozonation on the treatment of aniline wastewater by activated sludge process[J]. International Journal of Environmental Science and Technology, 2023, 20(11): 12167-12178.
[15]	TANG Taotao, CHEN Ying, DU Ye, et al. Effects of functional modules and bacterial clusters response on transmission performance of antibiotic resistance genes under antibiotic stress during anaerobic digestion of livestock wastewater[J]. Journal of Hazardous Materials, 2023, 441: 129870.
[16]	安莹, 张慧敏, 刘韵, 等. 高负荷活性污泥工艺污泥膨胀成因及控制[J]. 中国环境科学, 2025, 45(2): 768-775.
	AN Ying, ZHANG Huimin, LIU Yun, et al. Causes and control of sludge bulking in high load activated sludge process[J]. China Environmental Science, 2025, 45(2): 768-775.
[17]	LI Weiming, LIAO Xiwen, GUO Jinsong, et al. New insights into filamentous sludge bulking: The potential role of extracellular polymeric substances in sludge bulking in the activated sludge process[J]. Chemosphere, 2020, 248: 126012.
[18]	Junping LYU, WANG Yaqin, ZHONG Chen, et al. The effect of quorum sensing and extracellular proteins on the microbial attachment of aerobic granular activated sludge[J]. Bioresource Technology, 2014, 152: 53-58.
[19]	HE Qiulai, ZHANG Jing, GAO Shuxian, et al. A comprehensive comparison between non-bulking and bulking aerobic granular sludge in microbial communities[J]. Bioresource Technology, 2019, 294: 122151.
[20]	HE Shilong, CHEN Yi, QIN Meng, et al. Effects of temperature on anammox performance and community structure[J]. Bioresource Technology, 2018, 260: 186-195.
[21]	LASPIDOU Chrysi S, RITTMANN Bruce E. A unified theory for extracellular polymeric substances, soluble microbial products, and active and inert biomass[J]. Water Research, 2002, 36(11): 2711-2720.
[22]	LIU Xiaomeng, SHENG Guoping, LUO Hongwei, et al. Contribution of extracellular polymeric substances (EPS) to the sludge aggregation[J]. Environmental Science & Technology, 2010, 44(11): 4355-4360.
[23]	JIA Fangxu, YANG Qing, LIU Xiuhong, et al. Stratification of extracellular polymeric substances (EPS) for aggregated anammox microorganisms[J]. Environmental Science & Technology, 2017, 51(6): 3260-3268.
[24]	HAMMES Frederik, GOLDSCHMIDT Felix, VITAL Marius, et al. Measurement and interpretation of microbial adenosine tri-phosphate (ATP) in aquatic environments[J]. Water Research, 2010, 44(13): 3915-3923.
[25]	HUANG Hui, FAN Xuan, PENG Pengcheng, et al. Two birds with one stone: Simultaneous improvement of biofilm formation and nitrogen transformation in MBBR treating high ammonia nitrogen wastewater via exogenous N-acyl homoserine lactones[J]. Chemical Engineering Journal, 2020, 386: 124001.
[26]	FU Huimin, WANG Jinfeng, REN Hongqiang, et al. Acceleration of start-up of moving bed biofilm reactor at low temperature by adding specialized quorum sensing bacteria[J]. Bioresource Technology, 2022, 358: 127249.
[27]	高晨晨, 郑兴灿, 游佳, 等. 城市污水脱氮除磷系统的活性污泥菌群结构特征[J]. 中国给水排水, 2015, 31(23): 37-42.
	GAO Chenchen, ZHENG Xingcan, YOU Jia, et al. Structure characteristics of activated sludge microbial communities in nitrogen and phosphorus removal system of municipal wastewater[J]. China Water & Wastewater, 2015, 31(23): 37-42.
[28]	BARCZYNSKA Renata, SLIZEWSKA Katarzyna, LITWIN Mieczyslaw, et al. The effect of dietary fibre preparations from potato starch on the growth and activity of bacterial strains belonging to the phyla Firmicutes, Bacteroidetes, and Actinobacteria[J]. Journal of Functional Foods, 2015, 19: 661-668.
[29]	KONG Yunhong, XIA Yun, NIELSEN Jeppe Lund, et al. Structure and function of the microbial community in a full-scale enhanced biological phosphorus removal plant[J]. Microbiology, 2007, 153(12): 4061-4073.
[30]	SHI Linlin, ZHANG Ping, HE Yuhan, et al. Enantioselective effects of cyflumetofen on microbial community and related nitrogen cycle gene function in acid-soil[J]. Science of the Total Environment, 2021, 771: 144831.
[31]	Raquel RÍOS-CASTRO, CABO Adrián, TEIRA Eva, et al. High-throughput sequencing as a tool for monitoring prokaryote communities in a wastewater treatment plant[J]. Science of the Total Environment, 2023, 861: 160531.
[32]	ZHANG Meng, YAO Junqin, WANG Xiyuan, et al. The microbial community in filamentous bulking sludge with the ultra-low sludge loading and long sludge retention time in oxidation ditch[J]. Scientific Reports, 2019, 9(1): 13693.
[33]	刘小博. 脱氮除磷系统中污泥沉降性能影响研究[D]. 西安: 西安建筑科技大学, 2019.
	LIU Xiaobo. Study on the influence of sludge settling performance in nitrogen and phosphorus removal system[D]. Xi’an: Xi’an University of Architecture and Technology, 2019.
[34]	王萍, 余志晟. 污水处理厂污泥膨胀和污泥发泡的比较分析[J]. 微生物学通报, 2019, 46(8): 1971-1981.
	WANG Ping, YU Zhisheng. Comparative analysis of sludge bulking and sludge foaming in wastewater treatment plant[J]. Microbiology China, 2019, 46(8): 1971-1981.

编号	外源添加AHLs类型	信号分子浓度/μg·L^-1	运行方式
R1	C4-HSL	40	进水5min，曝气10h，静置沉淀1.5h，排水5min，闲置20min
R2	C6-HSL
R3	C8-HSL

编号	外源添加AHLs类型	信号分子浓度/μg·L^-1	运行方式
R1	C4-HSL	40	进水5min，曝气10h，静置沉淀1.5h，排水5min，闲置20min
R2	C6-HSL
R3	C8-HSL