Sustaining bioreactor efficacy in rural wastewater treatment under intermittent flow interruption: Elucidating microbial EPS-mediated stress adaptation mechanisms

LI Ya-jiao; JIANG Xiao-yu; CHI Yu-lei; ZHANG Bin-hong; REN Wu-ang; DING Xiao-qian; JU Kai; JIN Peng-kang

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China Environmental Science ›› 2025, Vol. 45 ›› Issue (5) : 2434-2442.

Sustaining bioreactor efficacy in rural wastewater treatment under intermittent flow interruption: Elucidating microbial EPS-mediated stress adaptation mechanisms

LI Ya-jiao¹, JIANG Xiao-yu¹, CHI Yu-lei¹, ZHANG Bin-hong², REN Wu-ang¹, DING Xiao-qian¹, JU Kai¹, JIN Peng-kang³

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Abstract

The adaptive resilience of microorganisms is crucial for maintaining the stable operation of Biotrickling filters under intermittent flow interruption. This process is intrinsically related to the ability of microorganism to store active substances as Extracellular Polymeric Substances (EPS). To elucidate this mechanism, a comparative analysis was conducted on biofilm structural characteristics, EPS compositional variations, and functional group transformations during an operation cycle of Biotrickling filters. The correlation between EPS-mediated stress response mechanisms and microbial activity maintenance/recovery was investigated. The results revealed that the removal of COD and NH₄⁺-N reached (95.56±1.10)% and (87.06±2.08)% respectively in the biotrickling filter operated under intermittent flow. Under the regulation of EPS, the biofilm showed a loose and porous structure. During flow interruption phases, microorganisms activated starvation adaptation strategies by converting carbon sources adsorbed in SB-EPS and metabolizing polysaccharides stored in SB-EPS. The structure integrity of microorganisms was maintained via synergistic effects of hydrophobic functional groups within EPS and polymer bridging interactions. Accordingly, an EPS-mediated stress adaptation system responsive to starvation-recovery alternations was established, enabling sustainable operation of Biotrickling filters.

Key words

biofilm structure / biotrickling filter / extracellular polymeric substances / intermittent flow interruption / stress mechanism

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LI Ya-jiao, JIANG Xiao-yu, CHI Yu-lei, ZHANG Bin-hong, REN Wu-ang, DING Xiao-qian, JU Kai, JIN Peng-kang. Sustaining bioreactor efficacy in rural wastewater treatment under intermittent flow interruption: Elucidating microbial EPS-mediated stress adaptation mechanisms[J]. China Environmental Science. 2025, 45(5): 2434-2442

References

[1] Xie Y, Zhang Q, Wu Q, et al. Novel adaptive activated sludge process leverages flow fluctuations for simultaneous nitrification and denitrification in rural sewage treatment [J]. Water Research, 2024,255: 121535.
[2] Cheng J, Chen Y, He Y, et al. Research of rural domestic sewage treatment processes in Ningbo [J]. IOP Conference Series: Earth and Environmental Science, 2019,358(2):022072.
[3] 杨亮,马军,陈志强.我国农村污水处理现状综述[J]. 中国给水排水, 2024,40(10):28-35. Yang L, Ma J, Chen Z G. Current situation of rural sewage treatment in China: a review [J]. China Water & Wastewater, 2024,40(10):28-35.
[4] 李冬,曹思雨,王琪,等.低表观气速间歇曝气AGS-SBR系统处理实际生活污水[J]. 中国环境科学, 2021,41(10):4588-4596. Li D, Cao S Y, Wang Q, et al. Low superficial gas velocity intermittent aeration AGS (aerobic granular sludge) SBR system oftreating domestic wastewater [J]. China Environmental Science, 2021,41(10): 4588-4596.
[5] 邵劲博,荣懿,刘星,等.基于污水排放特性的陕南村镇污水处理厂优化运行与节能降耗研究[J]. 给水排水, 2022,58(8):24-30. Shao J B, Rong Y, Liu X, et al. Study on rural wastewater discharge characteristics and optimal operation of typical township wastewater treatment plants in Southern Shaanxi [J]. Water & Wastewater Engineering, 2022,58(8):24-30.
[6] 王睿,张亮,谭映宇,等.自充氧层叠生物滤床在农村生活污水处理中的应用研究[J]. 环境与可持续发展, 2021,46(3):134-139. Wang R, Zhang L, Tan Y Y, et al. Research on application of selfoxygenation laminated biological filter bed in rural domestic sewage treatment [J]. Environment and Sustainable Development, 2021, 46(3):134-139.
[7] Shen S, Meng J, Zhang T, et al. Purification effect and microbial community structure of bio filter on rural dispersed sewage [J]. Heliyon, 2024,10(3):e25301.
[8] Chen P, Zhao W, Chen D, et al. Research progress on integrated treatment technologies of rural domestic sewage: A review [J]. Water, 2022,14(15):2439.
[9] Peng X, Yang W, Jin Q, et al. Biofilter-constructed wetland-trophic pond system: a new strategy for effective sewage treatment and agricultural irrigation in rural area [J]. Journal of Environmental Management, 2023,332:117436.
[10] Huang Y, Hu T, Lin B, et al. Microplastics-biofilm interactions in biofilm-based wastewater treatment processes: A review [J]. Environmental Pollution, 2024,361:124836.
[11] Wu Y, Wan A, Zhao B, et al. Single-stage MBBR using novel carriers to remove nitrogen in rural domestic sewage: The effect of carrier structure on biofilm morphology and SND [J]. Journal of Environmental Chemical Engineering, 2022,10(5):108267.
[12] Mpongwana N, Rathilal S. Exploiting biofilm characteristics to enhance biological nutrient removal in wastewater treatment plants [J]. Applied Sciences, 2022,12(15):7561.
[13] Characterization of stratified EPS and their role in the initial adhesion of anammox consortia [J]. Water Research, 2020,169:115223.
[14] He S, Zhao L, Feng L, et al. Mechanistic insight into the aggregation ability of anammox microorganisms: Roles of polarity, composition and molecular structure of extracellular polymeric substances [J]. Water Research, 2024,254:121438.
[15] Izadi P, Izadi P, Eldyasti A. Holistic insights into extracellular polymeric substance (EPS) in anammosx bacterial matrix and the potential sustainable biopolymer recovery: A review [J]. Chemosphere, 2021,274:129703.
[16] Zhao K, Wang J, Peng G, et al. Influence of composite fillers on sludge characteristics and extracellular polymeric substance composition and structure in the sequencing batch reactor [J]. Chemical Papers, 2022, 76(7):4147-4158.
[17] Yu G, He P, Shao L. Breakage and regrowth of sludge flocs by removal and readdition of extracellular polymeric substances fractions [J]. Environmental Engineering Science, 2009,26(10):1533-1540.
[18] Pan M, Li H, Han X, et al. Impact of hydrodynamic conditions on the production and distribution of extracellular polymeric substance in river biofilms [J]. Water, 2023,15(21):3821.
[19] Sheng G P, Zhang M L, Yu H Q. Characterization of adsorption properties of extracellular polymeric substances (EPS) extracted from sludge [J]. Colloids and Surfaces B: Biointerfaces, 2008,62(1):83-90.
[20] Su X, Zhang Z. Structural characteristics of extracellular polymeric substances (EPS) in membrane bioreactor and their adsorptive fouling [J]. Water Science and Technology, 2018,77(6):1537-1546.
[21] Yu W, Wen Q, Yang J, et al. Novel insights into extracellular polymeric substance degradation, hydrophilic/hydrophobic characteristics, and dewaterability of waste activated sludge pretreated by hydroxylamine enhanced fenton oxidation [J]. ACS ES&T Engineering, 2021,1(3):385-392.
[22] Gong X, Zhang L, Gong Q, et al. Rapid cultivation and enrichment of anammox bacteria solely using traditional activated sludge as inoculum and biocarrier in low-strength real sewage treatment [J]. Bioresource Technology, 2022,358:127354.
[23] Li Q, Abdelfattah A, Yu Y Y, et al. Assessment of the start-up of the passive aeration simultaneous nitrification and denitrification (PASND) process using activated sludge as a sole seed for low-energy C and N removal [J]. Environmental Science: Water Research & Technology, 2022,8(8):1731-1740.
[24] 魏复盛,齐文启.水和废水检测分析方法[M]. 北京:中国环境科学出版社, 2002:88-284. Wei F S, Qi W Q. Methods for monitoring and analysis of water and wastewater (fourth edition) [M]. Beijing: Chinese environmental science press, 2002:88-284.
[25] 顾超超,郭彦海,孙许超,等.曝气生物滤池生物膜胞外聚合物提取方法对比研究[J]. 东华大学学报(自然科学版), 2017,43(5):720-726. Gu C C, Guo Y H, Sun X C, et al. Comparative study on extracellular polymeric substance extraction method for biofilms in biological aerated filters [J]. Journal of Donghua University (Natural Science), 2017,43(5):720-726.
[26] Lim K, Parameswaran P. Critical evaluation of heat extraction temperature on soluble microbial products (SMP) and extracellular polymeric substances (EPS) quantification in wastewater processes [J]. Water Science and Technology, 2022,85(8):2318-2331.
[27] Hu Z, Liu J, Zheng W, et al. Highly-efficient nitrogen removal from domestic wastewater based on enriched aerobic/anoxic biological filters and functional microbial community characteristics [J]. Journal of Cleaner Production, 2019,238:117867.
[28] Li X, Huang Y, Guo Y, et al. Full-scale application and performance of a new multi-self-reflow decentralized wastewater treatment device: impact of hydraulic and pollutant loads [J]. Journal of Environmental Sciences, 2023,131:37-47.
[29] Yang F. Differences in exopolysaccharides of three microbial aggregates [J]. Environmental Technology, 2022,3(19):2909-2921.
[30] Tan Z, Abdoulahi M H, Yang X, et al. Carbon source type can affect tetracycline removal by pseudomonas sp. TC952through regulation of extracellular polymeric substances composition and production [J]. Science of the Total Environment, 2022,804:149907.
[31] Zhao X, Yang Y, Feng K, et al. Self-regulating microbiome networks ensure functional resilience of biofilms in sand biofilters during manganese load fluctuations [J]. Water Research, 2021,188:116473.
[32] Shi H X, Wang J, Liu S Y, et al. New insight into filamentous sludge bulking: potential role of AHL-mediated quorum sensing in deteriorating sludge floc stability and structure [J]. Water Research, 2022,212:118096.
[33] He S, Zhao L, Feng L, et al. Mechanistic insight into the aggregation ability of anammox microorganisms: roles of polarity, composition and molecular structure of extracellular polymeric substances [J]. Water Research, 2024,254:121438.
[34] Deng Z, Chen Y, Zhang C, et al. Improving nitrogen removal performance from rare earth wastewater via partial denitrification and anammox process with Fe(II) amendment [J]. Journal of Water Process Engineering, 2024,60:105131.
[35] 许炜怡,黄凯文,刘崇,等.高氮负荷下硫自养反硝化菌群的胞外聚合物和信号分子特征[J]. 中国环境科学, 2024,44(8):4314-4325. Xu Y Y, Huang K W, Liu C, et al. Characterization of extracellular polymer substances and acyl-homoserine lactones of sulfur-based autotrophic denitrification microbial community under high nitrate loading [J]. China Environmental Science, 2024,44(8):4314-4325.
[36] He S, Feng L, Zhao W, et al. Composition and molecular structure analysis of hydrophilic/hydrophobic extracellular polymeric substances (EPS) with impacts on sludge dewaterability [J]. Chemical Engineering Journal, 2023,462:142234.
[37] He S, Zhao L, Liu Y, et al. Multiple drivers and mechanisms of solid-water interfacial interactions in sludge dewatering: roles of polarity and molecular structure of extracellular polymeric substances [J]. Water Research, 2024,263:122180.
[38] Qiang A, Chen Y, Tang M, et al. The mechanism of extracellular polymeric substances in the formation of activated sludge flocs [J]. Colloids and Surfaces A: Physicochemical and Engineering Aspects, 2023,663:131009.
[39] Feng L J, Wang J J, Liu S C, et al. Role of extracellular polymeric substances in the acute inhibition of activated sludge by polystyrene nanoparticles [J]. Environmental Pollution, 2018,238:859-865.