title: Simultaneous removal of harmful algal blooms and microcystins using microorganism- and chitosan-modified local soil.
abstract: Cyanobacterial harmful algal blooms (cyano-HAB) and microcystins (MCs) can cause a potential threat to public health. Here, a method for simultaneous removal of cyano-HAB and MCs was developed using chitosan-modified local soil (MLS) flocculation plus microorganism-modified soil capping. The experiment was conducted in simulated columns containing algal water collected from Lake Taihu (China). More than 90% of algal cells and intracellular MCs were flocculated and removed from water using chitosan-MLS and the sunken flocs were treated by different capping materials including Pseudomonas sp. An18 modified local soil. During 40 days of incubation, dissolved MC-LR and MC-RR showed 10-fold increase in the flocculation-only system. The increase of MC-LR and MC-RR in water was reduced by 30 and 70% in soil capping treatments; however, the total content of MCs in the sediment-water column remained similar to that in the control and flocculation only systems. In contrast, both dissolved MCs and total MCs were reduced by 90% in Pseudomonas sp. An18 modified soil capping treatment. The high performance of toxin decomposition was due to the combined effects of flocculation and MC-degrading bacteria that embedded in the capping material, which prevents dilution of bacteria biomass, concentrates algal cells, confines released toxins, and enhances toxin biodegradation.
authors.affiliation: †Research Center for Eco-environmental Sciences, Chinese Academy of Sciences, 18 Shuangqing Road, Beijing 100085, China.|‡Institute of Biology, Guizhou Academy of Science, Guiyang 550009, China.
authors.forename: Hong
authors.initials: H
authors.lastname: Li
authors.affiliation: †Research Center for Eco-environmental Sciences, Chinese Academy of Sciences, 18 Shuangqing Road, Beijing 100085, China.
authors.forename: Gang
authors.initials: G
authors.lastname: Pan
mesh_terms: D001673:Biodegradation, Environmental; D049109:Cell Proliferation; D002681:China; D048271:Chitosan / Q000737:chemistry*; D000458:Cyanobacteria / Q000378:metabolism; D005427:Flocculation; D019015:Geologic Sediments / Q000737:chemistry; D057097:Harmful Algal Bloom; D060106:Lakes / Q000382:microbiology; D013058:Mass Spectrometry; D052998:Microcystins / Q000302:isolation & purification*; D011549:Pseudomonas / Q000166:cytology / Q000378:metabolism*; D012987:Soil / Q000737:chemistry*; D014867:Water / Q000737:chemistry
chemical_list: D052998:Microcystins; D012987:Soil; D014867:Water; C078588:microcystin; D048271:Chitosan