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Yu C, Liu Y, Zhang Y, Shen MZ, Wang JH, Chi ZY. Seawater Chlorella sp. biofilm for mariculture effluent polishing under environmental combined antibiotics exposure and ecological risk evaluation based on parent antibiotics and transformation products. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 939:173643. [PMID: 38821282 DOI: 10.1016/j.scitotenv.2024.173643] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/01/2024] [Revised: 05/21/2024] [Accepted: 05/28/2024] [Indexed: 06/02/2024]
Abstract
Mariculture effluent polishing with microalgal biofilm could realize effective nutrients removal and resolve the microalgae-water separation issue via biofilm scraping or in-situ aquatic animal grazing. Ubiquitous existence of antibiotics in mariculture effluents may affect the remediation performances and arouse ecological risks. The influence of combined antibiotics exposure at environment-relevant concentrations towards attached microalgae suitable for mariculture effluent polishing is currently lack of research. Results from suspended cultures could offer limited guidance since biofilms are richer in extracellular polymeric substances that may protect the cells from antibiotics and alter their transformation pathways. This study, therefore, explored the effects of combined antibiotics exposure at environmental concentrations towards seawater Chlorella sp. biofilm in terms of microalgal growth characteristics, nutrients removal, anti-oxidative responses, and antibiotics removal and transformations. Sulfamethoxazole (SMX), tetracycline (TL), and clarithromycin (CLA) in single, binary, and triple combinations were investigated. SMX + TL displayed toxicity synergism while TL + CLA revealed toxicity antagonism. Phosphorus removal was comparable under all conditions, while nitrogen removal was significantly higher under SMX and TL + CLA exposure. Anti-oxidative responses suggested microalgal acclimation towards SMX, while toxicity antagonism between TL and CLA generated least cellular oxidative damage. Parent antibiotics removal was in the order of TL (74.5-85.2 %) > CLA (60.8-69.5 %) > SMX (13.5-44.1 %), with higher removal efficiencies observed under combined than single antibiotic exposure. Considering the impact of residual parent antibiotics, CLA involved cultures were identified of high ecological risks, while medium risks were indicated in other cultures. Transformation products (TPs) of SMX and CLA displayed negligible aquatic toxicity, the parent antibiotics themselves deserve advanced removal. Four out of eight TPs of TL could generate chronic toxicity, and the elimination of these TPs should be prioritized for TL involved cultures. This study expands the knowledge of combined antibiotics exposure upon microalgal biofilm based mariculture effluent polishing.
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Affiliation(s)
- Chong Yu
- MOE Key Laboratory of Bio-Intelligent Manufacturing, School of Bioengineering, Dalian University of Technology, Dalian 116024, PR China
| | - Yang Liu
- MOE Key Laboratory of Bio-Intelligent Manufacturing, School of Bioengineering, Dalian University of Technology, Dalian 116024, PR China
| | - Ying Zhang
- MOE Key Laboratory of Bio-Intelligent Manufacturing, School of Bioengineering, Dalian University of Technology, Dalian 116024, PR China
| | - Ming-Zhi Shen
- MOE Key Laboratory of Bio-Intelligent Manufacturing, School of Bioengineering, Dalian University of Technology, Dalian 116024, PR China
| | - Jing-Han Wang
- MOE Key Laboratory of Bio-Intelligent Manufacturing, School of Bioengineering, Dalian University of Technology, Dalian 116024, PR China.
| | - Zhan-You Chi
- MOE Key Laboratory of Bio-Intelligent Manufacturing, School of Bioengineering, Dalian University of Technology, Dalian 116024, PR China
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Du J, Yan Z, Hu C, Wang K, Liu G, Jiang B, Song L, Xie H. Occurrence, distribution and risk assessment of antibiotics and pesticides in mariculture area around Liaodong Peninsula. MARINE POLLUTION BULLETIN 2024; 205:116588. [PMID: 38889666 DOI: 10.1016/j.marpolbul.2024.116588] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/21/2024] [Revised: 05/17/2024] [Accepted: 06/09/2024] [Indexed: 06/20/2024]
Abstract
Mariculture stands as a pivotal enterprise aimed at enhancing the quality of human existence. However, the utilization of antibiotics and pesticides in the mariculture process poses threats to both the environment and human well-being. Therefore, it is of great significance to investigate the occurrence, distribution and risk of antibiotics and pesticides in mariculture areas. In this study, 11 kinds of antibiotics and 12 kinds of pesticides were screened in four mariculture areas around Liaodong Peninsula in China. The pollution characteristics of pollutants were investigated in three different mariculture stages. The pollution in the reproduction stage was the most serious, indicating that mariculture may have a potential impact on the surrounding seawater. Health risk assessment results indicate that the pollutants have a significant risk to human health, therefore it is necessary to strengthen the control of chemicals used in mariculture in future.
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Affiliation(s)
- Jing Du
- Key Laboratory of Protection and Utilization of Aquatic Germplasm Resources, Ministry of Agriculture and Rural Affairs, Liaoning Ocean and Fisheries Science Research Institute, Dalian, Liaoning 116023, PR China
| | - Zhenhui Yan
- Key Laboratory of Industrial Ecology and Environmental Engineering (MOE), Dalian Key Laboratory on Chemicals Risk Control and Pollution Prevention Technology, School of Environmental Science and Technology, Dalian University of Technology, Linggong Road 2, Dalian 116024, PR China
| | - Chaokui Hu
- Key Laboratory of Protection and Utilization of Aquatic Germplasm Resources, Ministry of Agriculture and Rural Affairs, Liaoning Ocean and Fisheries Science Research Institute, Dalian, Liaoning 116023, PR China
| | - Kun Wang
- Key Laboratory of Protection and Utilization of Aquatic Germplasm Resources, Ministry of Agriculture and Rural Affairs, Liaoning Ocean and Fisheries Science Research Institute, Dalian, Liaoning 116023, PR China
| | - Guiying Liu
- Key Laboratory of Protection and Utilization of Aquatic Germplasm Resources, Ministry of Agriculture and Rural Affairs, Liaoning Ocean and Fisheries Science Research Institute, Dalian, Liaoning 116023, PR China
| | - Bing Jiang
- Key Laboratory of Protection and Utilization of Aquatic Germplasm Resources, Ministry of Agriculture and Rural Affairs, Liaoning Ocean and Fisheries Science Research Institute, Dalian, Liaoning 116023, PR China
| | - Lun Song
- Key Laboratory of Protection and Utilization of Aquatic Germplasm Resources, Ministry of Agriculture and Rural Affairs, Liaoning Ocean and Fisheries Science Research Institute, Dalian, Liaoning 116023, PR China.
| | - Huaijun Xie
- Key Laboratory of Industrial Ecology and Environmental Engineering (MOE), Dalian Key Laboratory on Chemicals Risk Control and Pollution Prevention Technology, School of Environmental Science and Technology, Dalian University of Technology, Linggong Road 2, Dalian 116024, PR China
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Pignattelli S, Provenza F, Rampih D, Crisci A, Renzi M. Ecotoxicological assessment, in freshwater environment, of wastewater sludge coupled and uncoupled with micro-polyvinyl chloride on algae and water fleas. WATER ENVIRONMENT RESEARCH : A RESEARCH PUBLICATION OF THE WATER ENVIRONMENT FEDERATION 2024; 96:e11089. [PMID: 39101386 DOI: 10.1002/wer.11089] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/29/2024] [Revised: 07/08/2024] [Accepted: 07/13/2024] [Indexed: 08/06/2024]
Abstract
In the frame of bioeconomy and circular economy, wastewater sludge (WS) could be a good candidate for its use in agriculture as fertilizer, due to its high content of organic matter, N and P, but on the other hand, it is full of toxicants such as heavy metal, microplastics, detergent, antibiotics, and so on that can reach groundwater and water bodies in leachate form. In this study, we have investigated different sludge concentrations in the eluate form, combined and not with PVC on two different freshwater organisms Selenastrum capricornutum and Daphnia magna, using ecotoxicity tests. At the endpoint, we have evaluated inhibition growth rate, oxidative stress, and pigments production for S. capricornutum, while in case of D. magna, we have assessed organism immobilization and development. From our results, it emerged that at the higher WS concentration, there was not inhibition growth rate, while at oxidative stress, it was higher in algae treated with WS and PVC. Higher Chl-a production was shown for algae treated with 0.3 g/L of sludge coupled with PVC, where higher phaeopigments production were recorded for algae treated with 0.3 g/L of WS. D. magna has shown an opposite trend when compared with algae, where at the highest WS concentrations supplied was corresponding to an increased mortality explaned as the highest immobility percentage. PRACTITIONER POINTS: Wastewater sludge is used in agriculture as fertilizer. PVC microplastic presence and associate ecotoxicity was tested. PVC presence increased oxidative stress in S. capricornutum. D. magna was significantly affected by sludge concentrations supplied.
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Affiliation(s)
- Sara Pignattelli
- Italy CNR-IBBR Institute of Bioscience and Bioresources, Sesto Fiorentino, Italy
| | - Francesca Provenza
- Dipartimento di Scienze della Vita, Università degli Studi di Trieste, Trieste, Italy
- Bioscience Research Center, Orbetello, Italy
| | | | - Alfonso Crisci
- Italy CNR-IBE Institute for Bioeconomy, Sesto Fiorentino, Italy
| | - Monia Renzi
- Dipartimento di Scienze della Vita, Università degli Studi di Trieste, Trieste, Italy
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Li H, Zhang W, Yan H, Gao P. Understanding the toxicity risk of antibiotic emissions of aquaculture from the perspective of fluctuations concentration. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2024; 351:124024. [PMID: 38685554 DOI: 10.1016/j.envpol.2024.124024] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/15/2024] [Revised: 04/08/2024] [Accepted: 04/21/2024] [Indexed: 05/02/2024]
Abstract
Organisms are generally exposed to target contaminant with stable concentrations in traditional ecotoxicological studies. However, it is difficult to truly represent the dynamics and complexity of actual aquatic pollution for risk management. Contaminants may enter nearby aquatic systems in pulsed exposure, thus resulting in that aquatic organisms will be exposed to contaminants at fluctuating concentrations. Especially during the season of summer, due to the changes in displacement or periodic emissions of veterinary antibiotics in aquaculture, algal blooms occur frequently in surrounding waters, thus leading to eutrophication of the water. Florfenicol (FFC) is currently widely used as a veterinary antibiotic, but the aquatic ecological risks of FFC under concentration fluctuations are still unknown. Therefore, the acute exposure, chronic exposure and pulsed exposure effects of FFC on Microcystis aeruginosa were investigated to comprehensively evaluate the ecological risk of FFC and raise awareness of the pulsed exposure mode. Results indicated that the toxic effects of FFC on M. aeruginosa were dominated by exposure mode, exposure duration, exposure frequency, and exposure concentration. The maximum growth inhibition rate of the 10 μg/L FFC treatment amounted to 4.07% during chronic exposure of 18 days. However, the growth inhibition rate decreased from 55.1% to 19.31% when algae was exposure to 10 μg/L FFC during the first pulsed exposure (8 h). Therefore, when the concentration of FFC was equal under chronic and pulsed exposure, FFC exhibited greater toxicity on M. aeruginosa in short pulsed exposure than in continuous exposure. In addition, repetitive pulsed exposure strengthened the resistance of M. aeruginosa on FFC. The adaptive regulation of algae was related to the duration and frequency of exposure. Above results suggested that traditional toxicity assessments lacked consideration for fluctuating concentrations during pollutant emissions, thus underestimating the environmental risk of contaminant. This investigation aims to facilitate the standardization of pulsed exposure.
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Affiliation(s)
- Huixiang Li
- School of Resource and Environmental Sciences, Hubei Biomass-Resource Chemistry and Environmental Biotechnology Key Laboratory, Wuhan University, Wuhan, Hubei, 430079, PR China; Central & Southern China Municipal Engineering Design and Research Institute Co LTD, Jiefang Park Avenue, Wuhan, Hubei, 430063, PR China
| | - Weihao Zhang
- School of Resource and Environmental Sciences, Hubei Biomass-Resource Chemistry and Environmental Biotechnology Key Laboratory, Wuhan University, Wuhan, Hubei, 430079, PR China
| | - Huimin Yan
- School of Resource and Environmental Sciences, Hubei Biomass-Resource Chemistry and Environmental Biotechnology Key Laboratory, Wuhan University, Wuhan, Hubei, 430079, PR China
| | - Pan Gao
- Key Laboratory of Molecular Biophysics of Ministry of Education, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, Hubei, 430074, PR China.
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Guo X, Chen H, Tong Y, Wu X, Tang C, Qin X, Guo J, Li P, Wang Z, Liu W, Mo J. A review on the antibiotic florfenicol: Occurrence, environmental fate, effects, and health risks. ENVIRONMENTAL RESEARCH 2024; 244:117934. [PMID: 38109957 DOI: 10.1016/j.envres.2023.117934] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/03/2023] [Revised: 12/09/2023] [Accepted: 12/11/2023] [Indexed: 12/20/2023]
Abstract
Florfenicol, as a replacement for chloramphenicol, can tightly bind to the A site of the 23S rRNA in the 50S subunit of the 70S ribosome, thereby inhibiting protein synthesis and bacterial proliferation. Due to the widespread use in aquaculture and veterinary medicine, florfenicol has been detected in the aquatic environment worldwide. Concerns over the effects and health risks of florfenicol on target and non-target organisms have been raised in recent years. Although the ecotoxicity of florfenicol has been widely reported in different species, no attempt has been made to review the current research progress of florfenicol toxicity, hormesis, and its health risks posed to biota. In this study, a comprehensive literature review was conducted to summarize the effects of florfenicol on various organisms including bacteria, algae, invertebrates, fishes, birds, and mammals. The generation of antibiotic resistant bacteria and spread antibiotic resistant genes, closely associated with hormesis, are pressing environmental health issues stemming from overuse or misuse of antibiotics including florfenicol. Exposure to florfenicol at μg/L-mg/L induced hormetic effects in several algal species, and chromoplasts might serve as a target for florfenicol-induced effects; however, the underlying molecular mechanisms are completely lacking. Exposure to high levels (mg/L) of florfenicol modified the xenobiotic metabolism, antioxidant systems, and energy metabolism, resulting in hepatotoxicity, renal toxicity, immunotoxicity, developmental toxicity, reproductive toxicity, obesogenic effects, and hormesis in different animal species. Mitochondria and the associated energy metabolism are suggested to be the primary targets for florfenicol toxicity in animals, albeit further in-depth investigations are warranted for revealing the long-term effects (e.g., whole-life-cycle impacts, multigenerational effects) of florfenicol, especially at environmental levels, and the underlying mechanisms. This will facilitate the evaluation of potential hormetic effects and construction of adverse outcome pathways for environmental risk assessment and regulation of florfenicol.
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Affiliation(s)
- Xingying Guo
- Guangdong Provincial Key Laboratory of Marine Disaster Prediction and Prevention, Shantou University, Shantou, 515063, China
| | - Haibo Chen
- Guangdong Provincial Key Laboratory of Marine Disaster Prediction and Prevention, Shantou University, Shantou, 515063, China
| | - Yongqi Tong
- Guangdong Provincial Key Laboratory of Marine Disaster Prediction and Prevention, Shantou University, Shantou, 515063, China
| | - Xintong Wu
- Guangdong Provincial Key Laboratory of Marine Disaster Prediction and Prevention, Shantou University, Shantou, 515063, China
| | - Can Tang
- Guangdong Provincial Key Laboratory of Marine Disaster Prediction and Prevention, Shantou University, Shantou, 515063, China
| | - Xian Qin
- State Key Laboratory of Marine Pollution, City University of Hong Kong, Kowloon, Hong Kong SAR, China
| | - Jiahua Guo
- Shaanxi Key Laboratory of Earth Surface System and Environmental Carrying Capacity, College of Urban and Environmental Sciences, Northwest University, Xi'an, 710127, China
| | - Ping Li
- Guangdong Provincial Key Laboratory of Marine Disaster Prediction and Prevention, Shantou University, Shantou, 515063, China
| | - Zhen Wang
- Guangdong Provincial Key Laboratory of Marine Disaster Prediction and Prevention, Shantou University, Shantou, 515063, China
| | - Wenhua Liu
- Guangdong Provincial Key Laboratory of Marine Disaster Prediction and Prevention, Shantou University, Shantou, 515063, China
| | - Jiezhang Mo
- Guangdong Provincial Key Laboratory of Marine Disaster Prediction and Prevention, Shantou University, Shantou, 515063, China.
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Dong Z, Hou X, Wang X, Shen Z, Pang H, Chen L, Yin Z, Ren F, Li W, Ge Y, Ning H, Hu D. Proteomic Analysis of the Mitochondrial Responses in P19 Embryonic Stem Cells Exposed to Florfenicol. TOXICS 2023; 11:992. [PMID: 38133393 PMCID: PMC10747307 DOI: 10.3390/toxics11120992] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/16/2023] [Revised: 11/29/2023] [Accepted: 12/04/2023] [Indexed: 12/23/2023]
Abstract
Florfenicol (FLO) has been shown to elicit diverse toxic effects in plants, insects, and mammals. Previously, our investigations revealed that FLO induced abnormal cardiac development and early embryonic mortality in chicken embryos. However, the effect of FLO on mitochondrial responses in stem cells remains unclear. In this study, we show that FLO significantly diminishes proliferation viability and obstructs the directed differentiation of P19 stem cells (P19SCs) into cardiomyocytes. Proteomic analysis revealed 148 differentially expressed proteins in response to FLO. Functional analysis has pinpointed FLO interference with biological processes associated with oxidative phosphorylation within the mitochondria. In alignment with the results of proteomic analysis, we confirmed that FLO inhibits the expression of both nuclear DNA-encoded and mitochondrial DNA-encoded subunits of the electron transport chain. Subsequent experiments demonstrated that FLO disrupts mitochondrial dynamics and induces the mitochondrial unfolded protein response to maintain mitochondrial homeostasis. These findings collectively highlight the significance of mitochondrial dynamics and the mitochondrial unfolded protein response to mediate the decreased proliferation viability and directed differentiation potential in P19SCs treated with FLO. In conclusion, this study provides a comprehensive overview of mitochondrial responses to FLO-induced cytotoxicity and enhances our understandings of the molecular mechanisms underlying FLO-induced embryonic toxicity.
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Affiliation(s)
- Zhihua Dong
- College of Animal Science and Technology, Henan Institute of Science and Technology, Xinxiang 453003, China; (Z.D.); (X.H.); (X.W.); (Z.S.); (H.P.); (L.C.); (Z.Y.); (F.R.); (Y.G.)
| | - Xueke Hou
- College of Animal Science and Technology, Henan Institute of Science and Technology, Xinxiang 453003, China; (Z.D.); (X.H.); (X.W.); (Z.S.); (H.P.); (L.C.); (Z.Y.); (F.R.); (Y.G.)
| | - Xueying Wang
- College of Animal Science and Technology, Henan Institute of Science and Technology, Xinxiang 453003, China; (Z.D.); (X.H.); (X.W.); (Z.S.); (H.P.); (L.C.); (Z.Y.); (F.R.); (Y.G.)
| | - Zihui Shen
- College of Animal Science and Technology, Henan Institute of Science and Technology, Xinxiang 453003, China; (Z.D.); (X.H.); (X.W.); (Z.S.); (H.P.); (L.C.); (Z.Y.); (F.R.); (Y.G.)
| | - Huiqing Pang
- College of Animal Science and Technology, Henan Institute of Science and Technology, Xinxiang 453003, China; (Z.D.); (X.H.); (X.W.); (Z.S.); (H.P.); (L.C.); (Z.Y.); (F.R.); (Y.G.)
| | - Lingli Chen
- College of Animal Science and Technology, Henan Institute of Science and Technology, Xinxiang 453003, China; (Z.D.); (X.H.); (X.W.); (Z.S.); (H.P.); (L.C.); (Z.Y.); (F.R.); (Y.G.)
| | - Zhihong Yin
- College of Animal Science and Technology, Henan Institute of Science and Technology, Xinxiang 453003, China; (Z.D.); (X.H.); (X.W.); (Z.S.); (H.P.); (L.C.); (Z.Y.); (F.R.); (Y.G.)
| | - Fei Ren
- College of Animal Science and Technology, Henan Institute of Science and Technology, Xinxiang 453003, China; (Z.D.); (X.H.); (X.W.); (Z.S.); (H.P.); (L.C.); (Z.Y.); (F.R.); (Y.G.)
| | - Weiguo Li
- Postdoctoral Research Station in Biological Sciences, Henan Normal University, Xinxiang 453003, China;
| | - Yaming Ge
- College of Animal Science and Technology, Henan Institute of Science and Technology, Xinxiang 453003, China; (Z.D.); (X.H.); (X.W.); (Z.S.); (H.P.); (L.C.); (Z.Y.); (F.R.); (Y.G.)
| | - Hongmei Ning
- College of Animal Science and Technology, Henan Institute of Science and Technology, Xinxiang 453003, China; (Z.D.); (X.H.); (X.W.); (Z.S.); (H.P.); (L.C.); (Z.Y.); (F.R.); (Y.G.)
| | - Dongfang Hu
- College of Animal Science and Technology, Henan Institute of Science and Technology, Xinxiang 453003, China; (Z.D.); (X.H.); (X.W.); (Z.S.); (H.P.); (L.C.); (Z.Y.); (F.R.); (Y.G.)
- Postdoctoral Research Station in Biological Sciences, Henan Normal University, Xinxiang 453003, China;
- Postdoctoral Research and Development Base, Henan Institute of Science and Technology, Xinxiang 453003, China
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Xue X, Su X, Zhou L, Ji J, Qin Z, Liu J, Li K, Wang H, Wang Z. Antibiotic-Induced Recruitment of Specific Algae-Associated Microbiome Enhances the Adaptability of Chlorella vulgaris to Antibiotic Stress and Incidence of Antibiotic Resistance. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2023; 57:13336-13345. [PMID: 37642958 DOI: 10.1021/acs.est.3c02801] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/31/2023]
Abstract
Insights into the symbiotic relation between eukaryotic hosts and their microbiome lift the curtain on the crucial roles of microbes in host fitness, behavior, and ecology. However, it remains unclear whether and how abiotic stress shapes the microbiome and further affects host adaptability. This study first investigated the effect of antibiotic exposure on behavior across varying algae taxa at the community level. Chlorophyta, in particular Chlorella vulgaris, exhibited remarkable adaptability to antibiotic stress, leading to their dominance in phytoplankton communities. Accordingly, we isolated C. vulgaris strains and compared the growth of axenic and nonaxenic ones under antibiotic conditions. The positive roles of antibiotics in algal growth were apparent only in the presence of bacteria. Results of 16S rRNA sequencing further revealed that antibiotic challenges resulted in the recruitment of specific bacterial consortia in the phycosphere, whose functions were tightly linked to the host growth promotion and adaptability enhancement. In addition, the algal phycosphere was characterized with 47-fold higher enrichment capability of antibiotic resistance genes (ARGs) than the surrounding water. Under antibiotic stress, specific ARG profiles were recruited in C. vulgaris phycosphere, presumably driven by the specific assembly of bacterial consortia and mobile genetic elements induced by antibiotics. Moreover, the antibiotics even enhanced the dissemination potential of the bacteria carrying ARGs from the algal phycosphere to broader environmental niches. Overall, this study provides an in-depth understanding into the potential functional significance of antibiotic-mediated recruitment of specific algae-associated bacteria for algae adaptability and ARG proliferation in antibiotic-polluted waters.
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Affiliation(s)
- Xue Xue
- College of Animal Science and Technology, Northwest A&F University, Yangling, Shaanxi 712100, China
| | - Xiaoyue Su
- College of Animal Science and Technology, Northwest A&F University, Yangling, Shaanxi 712100, China
| | - Linjun Zhou
- College of Animal Science and Technology, Northwest A&F University, Yangling, Shaanxi 712100, China
| | - Jiaqi Ji
- College of Animal Science and Technology, Northwest A&F University, Yangling, Shaanxi 712100, China
| | - Ziwei Qin
- College of Animal Science and Technology, Northwest A&F University, Yangling, Shaanxi 712100, China
| | - Jialin Liu
- College of Animal Science and Technology, Northwest A&F University, Yangling, Shaanxi 712100, China
| | - Kaiqi Li
- College of Animal Science and Technology, Northwest A&F University, Yangling, Shaanxi 712100, China
| | - He Wang
- College of Animal Science and Technology, Northwest A&F University, Yangling, Shaanxi 712100, China
| | - Zaizhao Wang
- College of Animal Science and Technology, Northwest A&F University, Yangling, Shaanxi 712100, China
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Jia J, Liu Q, Wu C. Microplastic and antibiotic proliferated the colonization of specific bacteria and antibiotic resistance genes in the phycosphere of Chlorella pyrenoidosa. JOURNAL OF HAZARDOUS MATERIALS 2023; 455:131618. [PMID: 37201280 DOI: 10.1016/j.jhazmat.2023.131618] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/11/2023] [Revised: 05/07/2023] [Accepted: 05/10/2023] [Indexed: 05/20/2023]
Abstract
Despite that the phycosphere was an important niche for the proliferation of various bacteria and antibiotic resistance genes (ARGs), the factors that affect the colonization of bacteria and ARGs in the phycosphere are still poorly understood. In this study, sterile C. pyrenoidosa co-cultured with bacteria from different sources and provided with polylactic acid microplastic (PLA MPs) and florfenicol (FF) was examined. Results showed that bacteria promoted the growth of C. pyrenoidosa and increased its chlorophyll contents. PLA MPs and FF also showed positive effects on C. pyrenoidosa due to the "Hormesis effect". The occurrence of bacteria in the phycosphere was significantly affected by their sources and the addition of PLA MPs and FF. However, the core microbiota of the phycosphere in each group was similar. Additionally, PLA MPs and FF proliferated the abundance of phenicol-related ARGs (especially floR) and mobile genetic elements in the phycosphere. Notably, PLA MPs and FF enhanced the abundance of Flavobacterium, a potential host of ARGs. Our results highlighted the important roles of bacteria in microalgae and demonstrated exogenous pollutants could promote the spread of ARGs between surrounding environments and the phycosphere, which provide new insights into the occurrence and spread of ARGs in the phycosphere.
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Affiliation(s)
- Jia Jia
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China
| | - Qian Liu
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China; University of Chinese Academy of Sciences, Beijing 100039, China
| | - Chenxi Wu
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China.
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Liu C, Feng C, Duan Y, Wang P, Peng C, Li Z, Yu L, Liu M, Wang F. Ecological risk under the dual threat of heavy metals and antibiotic resistant Escherichia coli in swine-farming wastewater in Shandong Province, China. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2023; 319:120998. [PMID: 36603760 DOI: 10.1016/j.envpol.2022.120998] [Citation(s) in RCA: 11] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/12/2022] [Revised: 12/30/2022] [Accepted: 12/31/2022] [Indexed: 06/17/2023]
Abstract
Mineral elements and antibiotic-resistant bacterial pollutants in livestock and poultry farms' wastewater are often sources of ecological and public health problems. To understand the heavy-metal pollution status and the characteristics of drug-resistant Escherichia coli (E. coli) in swine-farm wastewater in Shandong Province and to provide guidance for the rational use of mineral-element additives, common antibiotics, and quaternary ammonium compound disinfectants on swine farms, 10 mineral elements were measured and E. coli isolated from wastewater and its resistance to 29 commonly used antibiotics and resistance genes was determined. Finally, phylogenetic and multi-locus sequence typing (MLST) analyses was performed on E. coli. The results showed serious pollution from iron and zinc, with a comprehensive pollution index of 708.94 and 3.13, respectively. It is worth noting that average iron levels in 75% (12/16) of the districts exceed allowable limits. Multidrug-resistant E. coli were found in every city of the province. The E. coli isolated from swine-farm wastewater were mainly resistant to tetracyclines (95.3%), chloramphenicol (77.8%), and sulfonamides (62.2%), while antibiotic resistance genes for quinolones, tetracyclines, sulfonamides, aminoglycosides, and β-lactams were all more than 60%. The clonal complex 10 (CC10) was prevalent, and ST10 and ST48 were dominant in E. coli isolates. Multidrug-resistant E. coli were widely distributed, with mainly A genotypes. However, the mechanism of the effect of iron on antibiotic resistance needs more study in this area. Thus, further strengthening the prevention and control of iron and zinc pollution and standardizing the use of antibiotics and mineral element additives in the swine industry are necessary.
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Affiliation(s)
- Cong Liu
- Department of Veterinary Public Health, College of Veterinary Medicine & Shandong Provincial Key Laboratory of Animal Biotechnology and Disease Control and Prevention, Shandong Agricultural University, Taian, 271018, PR China.
| | - Chenglian Feng
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing, 100012, PR China
| | - Yuanpeng Duan
- Department of Veterinary Public Health, College of Veterinary Medicine & Shandong Provincial Key Laboratory of Animal Biotechnology and Disease Control and Prevention, Shandong Agricultural University, Taian, 271018, PR China
| | - Peng Wang
- Department of Veterinary Public Health, College of Veterinary Medicine & Shandong Provincial Key Laboratory of Animal Biotechnology and Disease Control and Prevention, Shandong Agricultural University, Taian, 271018, PR China
| | - Chong Peng
- Department of Veterinary Public Health, College of Veterinary Medicine & Shandong Provincial Key Laboratory of Animal Biotechnology and Disease Control and Prevention, Shandong Agricultural University, Taian, 271018, PR China
| | - Zixuan Li
- Department of Veterinary Public Health, College of Veterinary Medicine & Shandong Provincial Key Laboratory of Animal Biotechnology and Disease Control and Prevention, Shandong Agricultural University, Taian, 271018, PR China
| | - Lanping Yu
- Department of Veterinary Public Health, College of Veterinary Medicine & Shandong Provincial Key Laboratory of Animal Biotechnology and Disease Control and Prevention, Shandong Agricultural University, Taian, 271018, PR China
| | - Mengda Liu
- Laboratory of Zoonoses, China Animal Health and Epidemiology Center, Qingdao, Shandong, 266032, PR China
| | - Fangkun Wang
- Department of Veterinary Public Health, College of Veterinary Medicine & Shandong Provincial Key Laboratory of Animal Biotechnology and Disease Control and Prevention, Shandong Agricultural University, Taian, 271018, PR China.
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10
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Yuan Q, Zhang H, Qin C, Zhang H, Wang D, Zhang Q, Zhang D, Zhao J. Impact of emerging pollutant florfenicol on enhanced biological phosphorus removal process: Focus on reactor performance and related mechanisms. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 859:160316. [PMID: 36403846 DOI: 10.1016/j.scitotenv.2022.160316] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/04/2022] [Revised: 11/15/2022] [Accepted: 11/16/2022] [Indexed: 06/16/2023]
Abstract
Florfenicol (FF), an emerging pollutant antibiotic that is difficult to biodegrade, inevitably enters sewage treatment facilities with high level. To date, however, the performance and related mechanism of FF on enhanced biological phosphorus removal (EBPR) have not been reported. In order to fill this gap, this work investigated the potential impacts of FF on EBPR and revealed the relevant mechanisms. The effect of FF on EBPR was dose-dependent, that was, low dose had no effect on EBPR, while high FF concentration inhibited EBPR. Mechanism investigation showed that FF had no effect on anaerobic phosphate release, but reduced oxic phosphorus uptake. Three-dimensional Excitation-emission Matrix fluorescence spectroscopy and X-ray photoelectron spectroscopy analysis showed that FF affected the structure and components of activated sludge extracellular polymers (EPS). High content of FF stimulated sludge to secrete more EPS. High level of FF reduced the relative abundance of microorganisms responsible for biological phosphorus removal. Microbiological community structure analysis indicated 2.0 mg FF/L increased the relative abundance of Candidatus_Competibacter and Terrimonas from 9.22 % and 12.49 % to 19.00 % and 16.28 %, respectively, but significantly reduced the relative abundance of Chinophagaceae from 11.32 % to 0.38 %, compared with the blank.
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Affiliation(s)
- Qingjiang Yuan
- School of Environmental and Municipal Engineering, Qingdao University of Technology, Qingdao 266520, China
| | - Hongying Zhang
- School of Environmental and Municipal Engineering, Qingdao University of Technology, Qingdao 266520, China
| | - Chengzhi Qin
- School of Environmental and Municipal Engineering, Qingdao University of Technology, Qingdao 266520, China
| | - Huawei Zhang
- School of Environmental and Municipal Engineering, Qingdao University of Technology, Qingdao 266520, China
| | - Dongbo Wang
- College of Environmental Science and Engineering, Hunan University, Changsha 410082, China
| | - Qiuzhuo Zhang
- Shanghai Key Lab for Urban Ecological Processes and Eco-Restoration, Shanghai 200241, China
| | - Dalei Zhang
- School of Environmental and Municipal Engineering, Qingdao University of Technology, Qingdao 266520, China
| | - Jianwei Zhao
- School of Environmental and Municipal Engineering, Qingdao University of Technology, Qingdao 266520, China; College of Environmental Science and Engineering, Hunan University, Changsha 410082, China.
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11
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Chen H, Jin J, Hu S, Shen L, Zhang P, Li Z, Fang Z, Liu H. Metabolomics and proteomics reveal the toxicological mechanisms of florfenicol stress on wheat (Triticum aestivum L.) seedlings. JOURNAL OF HAZARDOUS MATERIALS 2023; 443:130264. [PMID: 36327828 DOI: 10.1016/j.jhazmat.2022.130264] [Citation(s) in RCA: 13] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/11/2022] [Revised: 10/16/2022] [Accepted: 10/24/2022] [Indexed: 06/16/2023]
Abstract
Although the ecological impacts of antibiotics have received attention worldwide, research on the toxicity of florfenicol is still limited. We conducted a metabolomic and proteomic study on wheat (Triticum aestivum L.) seedlings to reveal the toxicological mechanism of florfenicol. The growth of the wheat seedlings was found to be inhibited by florfenicol. Antioxidant enzyme activities (superoxide dismutase, peroxidase and catalase), malondialdehyde content and membrane permeability increased with increasing florfenicol concentration. The contents of chlorophyll and chlorophyll synthesis precursor substances (Proto IX, Mg-proto IX and Pchlide), photosynthetic and respiration rates, and chlorophyll fluorescence parameters decreased, indicating that photosynthesis was inhibited. The ultrastructure of chloroplasts was destroyed, as evidenced by the blurred membrane surface, irregular grana arrangement, irregular thylakoid lamella structure, and increased plastoglobuli number. Proteome analysis revealed that up-regulated proteins were highly involved in protein refolding, translation, oxidation-reduction, tricarboxylic acid cycle (TCA cycle), reactive oxygen species metabolic process, cellular oxidant detoxification, and response to oxidative stress. The down-regulated proteins were mainly enriched in photosynthesis-related pathways. In the metabolome analysis, the content of most of the metabolites in wheat leaves, such as carbohydrates and amino acids increased significantly (p < 0.05). Combined pathway analysis showed that florfenicol stress stimulated the TCA cycle pathway and downregulated the photosynthesis pathway.
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Affiliation(s)
- Hanmei Chen
- School of Environmental Science and Engineering, Instrumental analysis center, Zhejiang Gongshang University, Hangzhou 310018, PR China
| | - Jiaojun Jin
- School of Environmental Science and Engineering, Instrumental analysis center, Zhejiang Gongshang University, Hangzhou 310018, PR China
| | - Shuhao Hu
- School of Environmental Science and Engineering, Instrumental analysis center, Zhejiang Gongshang University, Hangzhou 310018, PR China
| | - Luoqin Shen
- School of Environmental Science and Engineering, Instrumental analysis center, Zhejiang Gongshang University, Hangzhou 310018, PR China
| | - Ping Zhang
- School of Environmental Science and Engineering, Instrumental analysis center, Zhejiang Gongshang University, Hangzhou 310018, PR China
| | - Zhiheng Li
- School of Environmental Science and Engineering, Instrumental analysis center, Zhejiang Gongshang University, Hangzhou 310018, PR China
| | - Zhiguo Fang
- School of Environmental Science and Engineering, Instrumental analysis center, Zhejiang Gongshang University, Hangzhou 310018, PR China
| | - Huijun Liu
- School of Environmental Science and Engineering, Instrumental analysis center, Zhejiang Gongshang University, Hangzhou 310018, PR China.
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12
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Qian Z, Na L, Bao-Long W, Tao Z, Peng-Fei M, Wei-Xiao Z, Sraboni NZ, Zheng M, Ying-Qi Z, Liu Y. Capabilities and mechanisms of microalgae on nutrients and florfenicol removing from marine aquaculture wastewater. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2022; 320:115673. [PMID: 35940008 DOI: 10.1016/j.jenvman.2022.115673] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/09/2022] [Revised: 06/09/2022] [Accepted: 07/02/2022] [Indexed: 06/15/2023]
Abstract
The regulations governing the discharge of marine aquaculture wastewater are becoming increasingly stringent, and the problems of nitrogen and phosphorus pollution and antibiotic residues in wastewater are serious. Microalgae-based treatment with the dual benefits of wastewater purification and microalgae resource recycling was regarded as the most promising technology in aquaculture wastewater treatment. Isochrysis galbana and Chlorella sp. were chosen to investigate antibiotic and nutrient removal mechanisms from aquaculture wastewater. FLO addition stimulated microalgae growth at low FLO concentrations (0.1 and 1 mg/L) but inhibited growth at 10 mg/L. The removal efficiency of DIN by Chlorella sp. and I. galbana after 7 days of cultivation was 66.4% and 25.8%, respectively. Linear curves were obtained between DIN concentration and cultivation duration, remove constant (k) increased as FLO concentration increased from 0 to 10 mg/L, and the highest value of k was obtained in both the Chlorella sp. and I. galbana groups at 10 mg/L. DIP concentrations in FLO-contained simulated aquaculture wastewater decreased sharply with the cultivation of Chlorella sp. and I. galbana, and DIP removal rate increased as FLO concentration increased. When the initial concentration of FLO was 0.1 mg/L, biodegradation by I. galbana accounted for 86.67% of FLO removal. In contrast, FLO removal with biodegradation and biosorption by Chlorella sp. was 89.74% and 3.72%, respectively. Furthermore, Chlorella sp. grown in MPBR demonstrated superior capability for antibiotic-containing marine aquaculture wastewater purification, with average removal rates of DIN and DIP of 81.2% and 100%, respectively. The high removal rate is related to membranes which can improve microalgae performance by decoupling SRT and HRT. For microalgae-based aquaculture wastewater, ammonia was the most crucial nitrogen source, followed by nitrate. These findings serve as a theoretical foundation for developing microalgae-based aquaculture wastewater treatment technology and eliminating antibiotics in aquaculture.
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Affiliation(s)
- Zhang Qian
- Key Laboratory of Environment Controlled Aquaculture (Dalian Ocean University) Ministry of Education, Dalian, 116023, China; College of Marine Science and Environment, Dalian Ocean University, Dalian, 116023, China
| | - Li Na
- Key Laboratory of Environment Controlled Aquaculture (Dalian Ocean University) Ministry of Education, Dalian, 116023, China; College of Marine Science and Environment, Dalian Ocean University, Dalian, 116023, China
| | - Wang Bao-Long
- Key Laboratory of Environment Controlled Aquaculture (Dalian Ocean University) Ministry of Education, Dalian, 116023, China; College of Marine Science and Environment, Dalian Ocean University, Dalian, 116023, China
| | - Zhang Tao
- Key Laboratory of Environment Controlled Aquaculture (Dalian Ocean University) Ministry of Education, Dalian, 116023, China; College of Marine Science and Environment, Dalian Ocean University, Dalian, 116023, China
| | - Ma Peng-Fei
- Key Laboratory of Environment Controlled Aquaculture (Dalian Ocean University) Ministry of Education, Dalian, 116023, China; College of Marine Science and Environment, Dalian Ocean University, Dalian, 116023, China
| | - Zhang Wei-Xiao
- College of Marine Science and Environment, Dalian Ocean University, Dalian, 116023, China
| | - Nusrat Zahan Sraboni
- College of Marine Science and Environment, Dalian Ocean University, Dalian, 116023, China; College of Aquaculture, Chattogram Veterinary and Animal Sciences University, Bangladesh
| | - Ma Zheng
- College of Marine Science and Environment, Dalian Ocean University, Dalian, 116023, China
| | - Zhang Ying-Qi
- Key Laboratory of Environment Controlled Aquaculture (Dalian Ocean University) Ministry of Education, Dalian, 116023, China; College of Marine Science and Environment, Dalian Ocean University, Dalian, 116023, China
| | - Ying Liu
- Key Laboratory of Environment Controlled Aquaculture (Dalian Ocean University) Ministry of Education, Dalian, 116023, China; College of Biosystems Engineering and Food Science, Zhejiang University, Hangzhou, 310058, China.
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13
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Hu D, Zhang B, Suo Y, Li Z, Wan Z, Zhao W, Chen L, Yin Z, Ning H, Ge Y, Li W. Molecular Mechanisms Underlying the Inhibition of Proliferation and Differentiation by Florfenicol in P19 Stem Cells: Transcriptome Analysis. Front Pharmacol 2022; 13:779664. [PMID: 35422703 PMCID: PMC9002123 DOI: 10.3389/fphar.2022.779664] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2021] [Accepted: 02/15/2022] [Indexed: 11/13/2022] Open
Abstract
Florfenicol (FLO), which is widely used in veterinary clinics and aquaculture, can disrupt the protein synthesis of bacteria and mitochondria and, thus, lead to antibacterial and toxic effects in plants, insects, and mammals. FLO was found to repress chicken embryonic development and induce early embryonic death previously, but the underlying mechanism is not fully understood. Clarifying the mechanism of FLO-induced embryonic toxicity is important to the research and development of new drugs and the rational use of FLO to ensure human and animal health and ecological safety. In this study, the effects of FLO on pluripotency, proliferation, and differentiation were investigated in P19 stem cells (P19SCs). We also identified differentially expressed genes and performed bioinformatics analysis to obtain hub genes and conducted some functional analysis. FLO inhibited the proliferation and pluripotency of P19SCs and repressed the formation of embryoid bodies derived from P19SCs. A total of 2,396 DEGs were identified using RNA-Seq in FLO-treated P19SCs, and these genes were significantly enriched in biological processes, such as angiogenesis, embryonic organ development, and morphogenesis of organs. Kyoto encyclopedia of genes and genome-based pathway analysis also showed that five relevant pathways, especially the canonical Wnt pathway, were engaged in FLO-induced toxicity of pluripotent stem cells. We further analyzed modules and hub genes and found the involvement of ubiquitin-mediated proteolysis, DNA replication, and cell cycle machinery in regulating the pluripotency and proliferation of FLO-treated P19SCs. In summary, our data suggest that FLO disrupts the signaling transduction of pathways, especially the canonical Wnt pathway, and further inhibits the expression of target genes involved in regulating DNA replication, cell cycle, and pluripotency. This phenomenon leads to the inhibition of proliferation and differentiation in FLO-treated P19SCs. However, further experiments are required to validate our findings and elucidate the potential mechanisms underlying FLO-induced embryonic toxicity.
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Affiliation(s)
- Dongfang Hu
- Postdoctoral Research Station in Biological Sciences, Henan Normal University, Xinxiang, China.,College of Animal Science and Technology, Henan Institute of Science and Technology, Xinxiang, China.,Postdoctoral Research Base, Henan Institute of Science and Technology, Xinxiang, China
| | - Bin Zhang
- College of Animal Science and Technology, Henan Institute of Science and Technology, Xinxiang, China
| | - Yu Suo
- College of Animal Science and Technology, Henan Institute of Science and Technology, Xinxiang, China
| | - Zhiyue Li
- College of Animal Science and Technology, Henan Institute of Science and Technology, Xinxiang, China
| | - Zhishuai Wan
- College of Animal Science and Technology, Henan Institute of Science and Technology, Xinxiang, China
| | - Weihua Zhao
- College of Animal Science and Technology, Henan Institute of Science and Technology, Xinxiang, China
| | - Lingli Chen
- College of Animal Science and Technology, Henan Institute of Science and Technology, Xinxiang, China
| | - Zhihong Yin
- College of Animal Science and Technology, Henan Institute of Science and Technology, Xinxiang, China
| | - Hongmei Ning
- College of Animal Science and Technology, Henan Institute of Science and Technology, Xinxiang, China
| | - Yaming Ge
- College of Animal Science and Technology, Henan Institute of Science and Technology, Xinxiang, China
| | - Weiguo Li
- Postdoctoral Research Station in Biological Sciences, Henan Normal University, Xinxiang, China
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14
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Mao Y, Yu Y, Ma Z, Li H, Yu W, Cao L, He Q. Azithromycin induces dual effects on microalgae: Roles of photosynthetic damage and oxidative stress. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2021; 222:112496. [PMID: 34243111 DOI: 10.1016/j.ecoenv.2021.112496] [Citation(s) in RCA: 46] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/12/2021] [Revised: 07/02/2021] [Accepted: 07/04/2021] [Indexed: 06/13/2023]
Abstract
Antibiotics are frequently detected in aquatic ecosystems, posing a potential threat to the freshwater environment. However, the response mechanism of freshwater microalgae to antibiotics remains inadequately understood. Here, the impacts of azithromycin (a broadly used antibiotic) on microalgae Chlorella pyrenoidosa were systematically studied. The results revealed that high concentrations (5-100 μg/L) of azithromycin inhibited algal growth, with a 96-h half maximal effective concentration of 41.6 μg/L. Azithromycin could weaken the photosynthetic activities of algae by promoting heat dissipation, inhibiting the absorption and trapping of light energy, impairing the reaction centre, and blocking electron transfer beyond QA. The blockage of the electron transport chain in the photosynthetic process further induced the generation of reactive oxygen species (ROS). The increases in the activities of superoxide dismutase, peroxidase and glutathione played important roles in antioxidant systems but were still not enough to scavenge the excessive ROS, thus resulting in the oxidative damage indicated by the elevated malondialdehyde level. Furthermore, azithromycin reduced the energy reserves (protein, carbohydrate and lipid) and impaired the cellular structure. In contrast, a hormesis effect on algal growth was found when exposed to low concentrations (0.5 and 1 μg/L) of azithromycin. Low concentrations of azithromycin could induce the activities of the PSII reaction centre by upregulating the mRNA expression of psbA. Additionally, increased chlorophyll b and carotenoids could improve the absorption of light energy and decrease oxidative damage, which further contributed to the increase in energy reserves (protein, carbohydrate and lipid). The risk quotients of azithromycin calculated in this study were higher than 1, suggesting that azithromycin could pose considerable ecological risks in real environments. The present work confirmed that azithromycin induced dual effects on microalgae, which provided new insight for understanding the ecological risk of antibiotics.
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Affiliation(s)
- Yufeng Mao
- Key Laboratory of Eco-Environment of Three Gorges Region, Ministry of Education, Chongqing University, Chongqing 400044, China; Key Laboratory of Hydraulic and Waterway Engineering, Ministry of Education, Chongqing Jiaotong University, Chongqing 400074, China; Lingzhi Environmental Protection Co., Ltd, Wuxi 214200, China
| | - Yang Yu
- Key Laboratory of Eco-Environment of Three Gorges Region, Ministry of Education, Chongqing University, Chongqing 400044, China
| | - Zixin Ma
- Key Laboratory of Eco-Environment of Three Gorges Region, Ministry of Education, Chongqing University, Chongqing 400044, China
| | - Hong Li
- Key Laboratory of Eco-Environment of Three Gorges Region, Ministry of Education, Chongqing University, Chongqing 400044, China
| | - Weiwei Yu
- Key Laboratory of Hydraulic and Waterway Engineering, Ministry of Education, Chongqing Jiaotong University, Chongqing 400074, China
| | - Li Cao
- Key Laboratory of Eco-Environment of Three Gorges Region, Ministry of Education, Chongqing University, Chongqing 400044, China
| | - Qiang He
- Key Laboratory of Eco-Environment of Three Gorges Region, Ministry of Education, Chongqing University, Chongqing 400044, China.
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