title: The removal of cyanobacteria and their metabolites through anoxic biodegradation in drinking water sludge.
abstract: The effects of environmental factors on cyanobacteria damage and microcystin-LR degradation in drinking water sludge were investigated under anoxic conditions. The rates of microcystin-LR release and degradation increased rapidly with the increasing temperature from 15°C to 40°C and the highest degradation rate of 99% was observed at 35°C within 10days. Compared to acidic conditions, microcystin-LR degraded more rapidly in weak alkali environments. In addition, the microbial community structures under different anoxic conditions were studied. The sequencing results showed that four phyla obtained from the DGGE profiles were as follows: Proteobacteria, Acidobacteria, Firmicutes and Cyanobacteria. Proteobacteria containing nine genera were the most common species. Pseudomonas, Methylosinus and Sphingomona all showed stronger activities and had significant increase as microcystin-LR degraded, so they should be responsible for the microcystin-LR degradation. This is the first report of Pseudomonas, Methylosinus and Sphingomonas as the microcystins-degrading microorganisms in anoxic drinking water sludge.
authors.affiliation: School of Environmental Science and Engineering, Shandong University, 27 Shanda Nan Road, Jinan 250100, China.
authors.forename: Guangxiang
authors.initials: G
authors.lastname: Ma
authors.affiliation: School of Environmental Science and Engineering, Shandong University, 27 Shanda Nan Road, Jinan 250100, China; Shandong Provincial Engineering Centre on Environmental Science and Engineering, 17923 Jingshi Road, Jinan 250061, China.
authors.forename: Haiyan
authors.initials: H
authors.lastname: Pei
authors.affiliation: School of Environmental Science and Engineering, Shandong University, 27 Shanda Nan Road, Jinan 250100, China; Shandong Provincial Engineering Centre on Environmental Science and Engineering, 17923 Jingshi Road, Jinan 250061, China. Electronic address: wenrongh@sdu.edu.cn.
authors.forename: Wenrong
authors.initials: W
authors.lastname: Hu
authors.affiliation: School of Environmental Science and Engineering, Shandong University, 27 Shanda Nan Road, Jinan 250100, China.
authors.forename: Xiangchao
authors.initials: X
authors.lastname: Xu
authors.affiliation: School of Environmental Science and Engineering, Shandong University, 27 Shanda Nan Road, Jinan 250100, China.
authors.forename: Chunxia
authors.initials: C
authors.lastname: Ma
authors.affiliation: School of Environmental Science and Engineering, Shandong University, 27 Shanda Nan Road, Jinan 250100, China.
authors.forename: Xiuqing
authors.initials: X
authors.lastname: Li
mesh_terms: D000693:Anaerobiosis; D001673:Biodegradation, Environmental; D044822:Biodiversity; D000458:Cyanobacteria / Q000235:genetics / Q000302:isolation & purification* / Q000378:metabolism*; D004275:DNA, Ribosomal / Q000235:genetics; D058645:Denaturing Gradient Gel Electrophoresis; D060766:Drinking Water / Q000382:microbiology*; D006863:Hydrogen-Ion Concentration; D008387:Marine Toxins; D052998:Microcystins / Q000302:isolation & purification; D008969:Molecular Sequence Data; D010802:Phylogeny; D017422:Sequence Analysis, DNA; D012722:Sewage / Q000382:microbiology*; D013696:Temperature
chemical_list: D004275:DNA, Ribosomal; D060766:Drinking Water; D008387:Marine Toxins; D052998:Microcystins; D012722:Sewage; C057862:cyanoginosin LR
keywords: Anoxic biodegradation; Bacteria; Cyanobacteria; Microcystin; Sludge