title: Interactions between Microcystis aeruginosa and coexisting amoxicillin contaminant at different phosphorus levels.
abstract: Microcystis aeruginosa was cultured with 0.05-5 mg L(-1) of phosphorus and exposed to 200-500 ng L(-1) of amoxicillin for seven days. Amoxicillin presented no significant effect (p>0.05) on the growth of M. aeruginosa at phosphorus levels of 0.05 and 0.2 mg L(-1), but stimulated algal growth as a hormesis effect at phosphorus levels of 1 and 5 mg L(-1). Phosphorus and amoxicillin affected the contents of chlorophyll-a, adenosine triphosphate (ATP) and malondialdehyde, the expression of psbA and rbcL, as well as the activities of adenosinetriphosphatase and glutathione S-transferase in similar manners, but regulated the production and release of microcystins and the activities of superoxide dismutase and peroxidase in different ways. Increased photosynthesis activity was related with the ATP consumption for the stress response to amoxicillin, and the stress response was enhanced as the phosphorus concentration increased. The biodegradation of amoxicillin by M. aeruginosa increased from 11.5% to 28.2% as the phosphorus concentration increased. Coexisting amoxicillin aggravated M. aeruginosa pollution by increasing cell density and concentration of microcystins, while M. aeruginosa alleviated amoxicillin pollution via biodegradation. The interactions between M. aeruginosa and amoxicillin were significantly regulated by phosphorus (p<0.05) and led to a complicated situation of combined pollution.
authors.affiliation: Shandong Provincial Key Laboratory of Water Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Shandong University, Jinan 250100, PR China. Electronic address: liuying2010@sdu.edu.cn.
authors.forename: Ying
authors.initials: Y
authors.lastname: Liu
authors.affiliation: Shandong Provincial Key Laboratory of Water Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Shandong University, Jinan 250100, PR China.
authors.forename: Shi
authors.initials: S
authors.lastname: Chen
authors.affiliation: Shandong Urban and Rural Planning Design Institute, Jinan 250013, China.
authors.forename: Xiao
authors.initials: X
authors.lastname: Chen
authors.affiliation: Shandong Provincial Key Laboratory of Water Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Shandong University, Jinan 250100, PR China.
authors.forename: Jian
authors.initials: J
authors.lastname: Zhang
authors.affiliation: Shandong Provincial Key Laboratory of Water Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Shandong University, Jinan 250100, PR China.
authors.forename: Baoyu
authors.initials: B
authors.lastname: Gao
mesh_terms: D000658:Amoxicillin / Q000032:analysis / Q000494:pharmacology*; D002734:Chlorophyll / Q000378:metabolism; D000077194:Chlorophyll A; D004784:Environmental Monitoring; D015870:Gene Expression / Q000187:drug effects; D046931:Microcystis / Q000187:drug effects* / Q000254:growth & development / Q000378:metabolism; D010758:Phosphorus / Q000032:analysis*; D010788:Photosynthesis / Q000187:drug effects* / Q000235:genetics; D014871:Water Microbiology; D014874:Water Pollutants, Chemical / Q000032:analysis / Q000494:pharmacology*
chemical_list: D014874:Water Pollutants, Chemical; D002734:Chlorophyll; D010758:Phosphorus; D000658:Amoxicillin; D000077194:Chlorophyll A
keywords: Adenosinetriphosphatase; Antioxidant responses; Biodegradation; Combined pollution; Hormesis