TY - JOUR
T1 - Effects of different algaecides on the photosynthetic capacity, cell integrity and microcystin-LR release of Microcystis aeruginosa
AU - Zhou, Shiqing
AU - Shao, Yisheng
AU - Gao, Naiyun
AU - Deng, Yang
AU - Qiao, Junlian
AU - Ou, Huase
AU - Deng, Jing
PY - 2013/10/1
Y1 - 2013/10/1
N2 - Bench scale tests were conducted to study the effects of four common algaecides, including copper sulfate, hydrogen peroxide, diuron and ethyl 2-methylacetoacetate (EMA) on the photosynthetic capacity, cell integrity and microcystin-LR (MC-LR) release of Microcystis aeruginosa. The release of potassium (K+) from cell membrane during algaecide exposure was also analyzed. The three typical photosynthetic parameters, including the effective quantum yield (Fe), photosynthetic efficiency (α) and maximal electron transport rate (rETRmax), were measured by a pulse amplitude modulated (PAM) fluorometry. Results showed that the photosynthetic capacity was all inhibited by the four algaecides, to different degrees, by limiting the energy capture in photosynthesis, and blocking the electron transfer chain in primary reaction. For example, at high diuron concentration (7.5mgL-1), Fe, α and rETRmax decreased from 0.46 to 0.19 (p<0.01), from 0.20 to 0.01 (p<0.01) μmol electrons m-2s-1/μmol photons m-2s-1, and from 160.7 to 0.1 (p<0.001) μmolm-2s-1 compared with the control group after 96h of exposure, respectively. Furthermore, the increase of algaecide dose could lead to the cell lysis, as well as release of intracellular MC-LR that enhanced the accumulation of extracellular MC-LR. The order of MC-LR release potential for the four algaecides was CuSO4>H2O2>diuron>EMA.
AB - Bench scale tests were conducted to study the effects of four common algaecides, including copper sulfate, hydrogen peroxide, diuron and ethyl 2-methylacetoacetate (EMA) on the photosynthetic capacity, cell integrity and microcystin-LR (MC-LR) release of Microcystis aeruginosa. The release of potassium (K+) from cell membrane during algaecide exposure was also analyzed. The three typical photosynthetic parameters, including the effective quantum yield (Fe), photosynthetic efficiency (α) and maximal electron transport rate (rETRmax), were measured by a pulse amplitude modulated (PAM) fluorometry. Results showed that the photosynthetic capacity was all inhibited by the four algaecides, to different degrees, by limiting the energy capture in photosynthesis, and blocking the electron transfer chain in primary reaction. For example, at high diuron concentration (7.5mgL-1), Fe, α and rETRmax decreased from 0.46 to 0.19 (p<0.01), from 0.20 to 0.01 (p<0.01) μmol electrons m-2s-1/μmol photons m-2s-1, and from 160.7 to 0.1 (p<0.001) μmolm-2s-1 compared with the control group after 96h of exposure, respectively. Furthermore, the increase of algaecide dose could lead to the cell lysis, as well as release of intracellular MC-LR that enhanced the accumulation of extracellular MC-LR. The order of MC-LR release potential for the four algaecides was CuSO4>H2O2>diuron>EMA.
KW - Cell lysis
KW - Cyanobacteria
KW - Microcystin-LR
KW - PAM
KW - Photosynthesis
UR - http://www.scopus.com/inward/record.url?scp=84879477339&partnerID=8YFLogxK
U2 - 10.1016/j.scitotenv.2013.05.064
DO - 10.1016/j.scitotenv.2013.05.064
M3 - Article
C2 - 23792253
AN - SCOPUS:84879477339
SN - 0048-9697
VL - 463-464
SP - 111
EP - 119
JO - Science of the Total Environment
JF - Science of the Total Environment
ER -