SCIENCE OF THE TOTAL ENVIRONMENT
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2019
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IF 5.589
Changwei Li,Lihua Lan,Musa Abubakar Tadda,Songming Zhu,Zhangying Ye,Dezhao Liu
This study investigated the relation between 17 β -estradiol (E2) degradation and nitrification in synthetic mariculture wastewater by ammonia oxidizing bacterium Nitrosomonas europaea and moving bed biofilm reactor (MBBR). Batch experiments showed that E2 degradation by N. europaea in wastewater followed zero-order reaction kinetics (r 2 = 0.944, 4.07 μg/ L h − 1 ) when ammonia presented. Nitrite yield in N. europaea inoculation decreased by 77.8% exposed to 1 mg/L E2. The inhibitory impact on ammonia oxidation was enhanced with increasing E2 dosage from 50 ng/L to 1 mg/L. Notably, E2 as low as 50 ng/L still had significant interference with nitrite production, bacterial density and ammonia monooxygenase (AMO) activity of N. europaea . Still, the following continuous 68-day degradation test revealed that 84.5%–98.7% E2 could be removed by a bench-scale MBBR. Whereas, ammonia removal remarkably decreased from 94.7% ± 2.1% to 85.6% ± 2.1% ( p < .05) along with the enhanced E2 removal (from 84.5% ± 2.0% to 98.7% ± 0.4%, p < .05) when inlet E2 increased from 10 μg/L to 1 mg/L, indicating the great role of heterotrophs in E2 degradation. In contrast, nitrite oxidation was not affected upon E2 exposure irrespective of E2 concentrations. In summary, nitrification was effective in removing E2, while E2 interfered with ammoxidation process, but this interference was negligible at the reactor level given the low level of E2 in practical field conditions.
研究领域:
环境工程
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微生物学
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废水处理
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产品关联
DOI
PubMed
高影响因子
CHEMICAL ENGINEERING JOURNAL
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2017
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IF 6.216
Xiaojing Zhang,Yue Zhou,Boyang Yu,Nan Zhang,Lina Wang,Haoqiang Fu,Jie Zhang
Autotrophic nitrogen removal is an innovative and economical nitrogen removal technology, in which partial nitrification (PN) is the key component. It is necessary to clear the impact of CuO nanoparticles (CuO NPs) on PN process since the wide application increased their opportunity for entering into wastewater. In this study, the short-term and long-term effects of CuO NPs on ammonia removal, extracellular polymeric substance (EPS) production and microbial community were investigated. Results suggested that CuO NPs in 1 mg L −1 had slight effect on PN, while that in 3–10 mg L −1 enhanced ammonia oxidation in the short-term exposure. In the long-term exposure experiment, CuO NPs with low concentration (≤5 mg L −1 ) improved both the bioactivity and relative abundance of ammonia-oxidizing bacteria (AOB). The suppression threshold on PN process of CuO NPs in short-term exposure was 30 mg L − 1 , while that in long-term exposure decreased to 10 mg L − 1 due to the adsorption and accumulation of NPs. Nitrosomonas was the predominant AOB in PN reactors, it showed better tolerance to CuO NPs and performed the best performance when CuO NPs was 5 mg L −1 . Long-term exposure within CuO NPs led to organisms death and resulted in the decrease of EPS.
研究领域:
环境工程
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废水处理
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微生物学
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纳米技术
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产品关联
DOI
高影响因子
WATER RESEARCH
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2025
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IF 12.4
Jiazheng Ding,Danyang Wang,Bin Ji,Anjie Li,Xiao-yan Li
Algal-bacterial granular sludge technology holds significant promise for treating municipal wastewater with carbon emission reduction. However, its practical application has been constrained by the long startup period. In this study, bio-hydrogels co-encapsulating autotrophic ammonia-oxidizing bacteria ( Nitrosomonas europaea ) and photomixotrophic microalgae ( Chlorella vulgaris ) were used in a microalgal-bacterial granules system (MBGS) for the treatment of low C/N wastewater. The operating conditions of the MBGS system included inoculation volume ratio of 1:6 (bio-hydrogel granules: wastewater), initial biomass of 0.33 g suspended solids (SS) /L, light intensity of 300 μmol/m 2 ·s, and no aeration. The results showed that this strategy reduced the typical MBGS startup period to just 6 days, with biomass accumulation (1.53 g SS/L, >4 g SS/L after running 120 days) and efficient chemical oxygen demand (COD) and total nitrogen (TN) removal (effluent COD <20.00 mg/L and TN <2.50 mg/L). Transcriptomic analysis revealed that the symbiosis with Nitrosomonas significantly upregulated the expression of the PetH gene, which encodes a reductase ( EC:1.18.1.2 ) in the photosynthetic system of Chlorella (log₂ fold change=13.63), thereby enhancing the supply of NADPH required for the Calvin cycle. Concurrently, the expression of the rbcL gene, encoding the large subunit of Rubisco in Chlorella , was upregulated by 1.4-fold, which promoted photosynthetic carbon fixation. The symbiosis also suppressed heterotrophic metabolism in Chlorella , as evidenced by downregulation of 72.5 % of genes in glycolysis and the tricarboxylic acid cycle, thereby mitigating the adverse effects of encapsulating material biodegradation on the bio-hydrogel structure. In addition, cell proliferation of Chlorella was stimulated (over 13-fold upregulation of DNA replication licensing factors MCM5 and MCM6), which increased biomass and nutrient removal efficiency. Furthermore, a higher light intensity of 400 μmol/m²/s promoted a significant increase in extracellular polymeric substances (EPS) content (106.76 mg/g SS), improved granule stability (integrity coefficient < 20 %), and enhanced biomass production (4.68 g SS/L after 120 days of operation). These findings highlight a promising strategy for sustainable wastewater treatment.
研究领域:
环境工程
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微生物生态学
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生物技术
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废水处理
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光合作用
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产品关联
DOI
PubMed
高影响因子
Journal of Ocean University of China
·
2020
·Vol. 19
·期 4
·865-873
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IF 0.802
Zheng Bingbing,Pang Wenhui,Zhao Yangguo,Guo Liang,Gao Mengchun,Jin Chunji,She Zonglian
The wide application of antibiotics in aquaculture requires an efficient treatment of the wastewater before discharging it into the environment. During the wastewater treatment, the influence of antibiotics on the performance of bioreactor should be well revealed due to their toxicity to the functional microbial community. In this study, the effect of feeding 10–30 mgL −1 sulfamethoxazole (SMX) in influent on the performance of an anoxic/oxic-moving bed biofilm reactor (A/O-MBBR) treating mariculture waste-water and the responding change of biofilm microbial communities was investigated. The COD average removal rate remained at 94.61%–97.34% with the dosage of SMX. Compared with that, the nitrifying removals of NH 4 + -N and NO 2 − -N were violently inhibited by 30 mgL −1 SMX and denitrifying removal of the NO 3 − -N decreased obviously with 20 mgL −1 or more SMX. The microbial community in the successful startup bioreactor was relatively abundant, while the diversity of microbial community decreased with the increase of feeding SMX. The salt-tolerant and SMX-resistant genera Arcobacter, Thiothrix, Desulfuromusa and Nitrosomonas were gradually enriched and finally played a vital role in converting COD and recycling nitrogen and sulfur. Hence, the present A/O-MBBR reactor with the salt-tolerant functional microbiota achieved efficient removal of pollutants in the presence of low concentration (e.g., 10 mg L −1 ) SMX.
研究领域:
环境工程
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微生物学
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废水处理
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DOI
高影响因子
JOURNAL OF HAZARDOUS MATERIALS
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2019
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IF 7.65
Yongpeng Ma,Denghui Wei,Xiaojing Zhang,Haoqiang Fu,Tao Chen,Jinping Jia
Anaerobic ammonium oxidation (Anammox) was an innovative process for nitrogen removal. In this study, CuO nanoparticles (NPs) was step-wise increasingly added to an MBR-based partial nitrification system, to investigate its feasibility for inducing Anammox and establishing autotrophic nitrogen removal system. Results showed that when CuO NPs was elevated to 5 mg L −1 , Anammox was successfully induced. The relative abundance of Nitrosomonas reached 13.73% while Candidatus Kuenenia increased to 4.79% from 0.46%, these two bacteria cooperatively contributed to the autotrophic nitrogen removal and improved the nitrogen removal rate (NRR) to 0.56 kg m -3 d −1 in 20 mg L −1 NPs. However, 50 mg L −1 NPs deeply suppressed the functional bacteria and decreased NRR to 0.14 kg m -3 d −1 . Finally, the NPs removal, transformation and adsorption in the system were evaluated. It was concluded that CuO NPs in low concentration (5 mg L −1 ) was effective for inducing Anammox and contributed to the survival of Anammox bacteria. The mechanism for inducing Anammox was attributed to the aggregation of CuO NPs which enabled the attached growth of AAOB as well as the suitable survival condition supplied by MBR.
研究领域:
环境工程
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微生物学
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水处理技术
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产品关联
DOI
PubMed
高影响因子
CHEMOSPHERE
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2022
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IF 8.943
Xiaoqi Dong,Zidan Huang,Xingxing Peng,Xiaoshan Jia
A novel coupled yeast-sludge system (CYSS) was constructed by the yeast Candida sp. PNY integrated with activated sludge to treat non-sterile mainstream wastewater. After 240-day cultivation, compared with single activated sludge , simultaneous removal efficiency of total organic carbon (TOC), nitrogen and phosphorus increased by 19.5% (176.34 mg TOC g −1 d −1 ), 21.3% (11.25 mg TN g −1 d −1 ) and 15.0% (6.95 mg TP g −1 d −1 ), respectively, while the amount of sludge reduced by 50%. Amplicon sequencing analysis showed that the abundance of Nitrosomonas , Nitrospira , Zoogloea , Dechloromonas , and Candidatus Accumulibacter significantly decreased to 0% on Day 200. Abundance of nirS and nirK for denitrification significantly decreased in CYSS by quantitative PCR (qPCR), and the copies of nirS and nirK were 3.37-fold and 1.71-fold decrease from Day 0 to Day 240, respectively. The results of Fluorescence in situ hybridization and co-occurrence network showed that Candida sp. PNY predominated its distribution in CYSS, and strongly connected with environmental variables based on network analysis. Furthermore, this study reconstructed the carbon, nitrogen and phosphorus metabolic pathways of the CYSS based on metagenomics .
研究领域:
环境工程
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微生物学
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废水处理
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生物技术
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）