水生态学杂志2025，Vol.46Issue(4)：35-47,13.DOI:10.15928/j.1674-3075.202411150001
菌藻颗粒污泥系统对聚苯乙烯微/纳塑料急性胁迫的响应
Response of Microalgal-bacterial Granular Sludge to Polystyrene Micro(nano)Particles
摘要
Abstract
Microalgal-bacterial granular sludge(MBGS)is characterized by low energy consumption,strong resistance to environmental stressors,and high recycling potential.These characteristics give MB-GS good potential for broad application in wastewater treatment and it has garnered significant attention.Because micro(nano)plastics are a common constituent of wastewater,we investigated the effects of ex-posure to microplastics(MPs)and nanoplastics(NPs)on MBGS performance.In this study,acute expo-sure to polystyrene(PS)micro(nano)particles was used to evaluate the effect of MPs and NPs on MBGS performance.A control group and six exposure groups were prepared,including two PS particle sizes(10 μm MPs,100 nm NPs),each prepared at three concentrations(50,100,200 mg/L).Physiological and bio-chemical parameters of the MBGS in each group were measured after 24 hours of exposure,focusing on nitrogen removal(nitrogen removal rate and nitrogen removal enzyme activity),reactive oxygen species(ROS)content,lactate dehydrogenase(LDH)content,microcystin content,necrotic cell quantity,content and composition of extracellular polymeric substances(EPS),and sludge aggregation.Results led to four conclusions:(1)Exposure to both MPs and NPs significantly reduced the nitrogen removal rate(NRR)and inhibited the nitrate reductase(NR)activity of MBGS relative to the control.As anticipated,the high PS treatment(200 mg/L)produced the largest decreases in specific nitrate oxidation rate(SNOR),44.77%(MPs)and 50.78%(NPs),and in NR activity,72.4%(MPs)and 75.4%(NPs).(2)Exposure to MPs and NPs,resulted in microbial oxidative stress,with elevated ROS levels damaging cell membranes and in-creasing the release of lactate dehydrogenase(LDH).Secretion of microcystin increased,inhibiting micro-bial growth and disrupting cell structures,ultimately leading to cell death.Compared to MPs,NPs caused more severe cellular damage,leading to a higher rate of cell death.(3)Exposure to MPs and NPs also re-duced EPS secretion,weakening protection for both bacteria and microalgae.The ratio of extracellular protein to extracellular polysaccharides in EPS decreased and the decline in tryptophan and aromatic pro-tein within the extracellular protein fraction reduced MBGS stability.(4)Zeta potential,contact angle,and surface thermodynamic analyses revealed that MPs and NPs exposure reduced the hydrophobicity of MB-GS microbial cells,increased electrostatic repulsion and diminished MBGS aggregation.In conclusion,acute exposure to polystyrene MPs and NPs significantly decreased nitrogen removal and reduced MBGS aggregation.关键词
菌藻颗粒污泥/聚苯乙烯微/纳塑料/急性胁迫/聚集性能Key words
microalgal-bacterial granular sludge/polystyrene micro(nano)plastics/acute exposure/aggre-gation capacity分类
资源环境引用本文复制引用
卞振华,高晚晴,张宇鑫,李世琪,李为瑾,吴玮,李瀚翔..菌藻颗粒污泥系统对聚苯乙烯微/纳塑料急性胁迫的响应[J].水生态学杂志,2025,46(4):35-47,13.基金项目
江苏省环境科学与工程重点实验室开放基金(JSHJZDSYS-202203). （JSHJZDSYS-202203）
