Cyanobacteria is one of the major sources of toxins in freshwater. These microorganisms are highly adaptive to changing environmental conditions. In this study, the occurrence of toxin producing cyanobacteria in Lagun...Cyanobacteria is one of the major sources of toxins in freshwater. These microorganisms are highly adaptive to changing environmental conditions. In this study, the occurrence of toxin producing cyanobacteria in Laguna de Bay and factors affecting its occurrence and growth were determined. The presence ofMicrocystis aeruginosa was positively correlated with nitrate (NO3) and iron (Fe^2+) with correlation coefficient of +0.72972 and +0.91063, respectively. It is negatively correlated with occurrence of sunshine (in days) and turbidity with correlation -0.79055 and -0.93531, respectively.展开更多
The transformation profiles of polycyclic aromatic hydrocarbons (PAHs) by pure laccases from Trametes versicolor and Pycnoporus sanguineus, and the optimal reaction conditions (acetonitrile concentration, pH, tempe...The transformation profiles of polycyclic aromatic hydrocarbons (PAHs) by pure laccases from Trametes versicolor and Pycnoporus sanguineus, and the optimal reaction conditions (acetonitrile concentration, pH, temperature and incubation time) were determined. Anthracene was the most transformable PAH by both laccases, followed by benzo[a]pyrene, and benzo[a]anthracene. Laccase-mediator system (LMS) could not only improve the PAH oxidation but also extend the substrate types compared to laccase alone. 5e/0 or 10~ (v/v) of acetonitrile concentration, pH 4, temperature of 40 ~C, and incubation time of 24 h were most favorable for anthracene oxidation by laccase from T. versicolor or P. sanguineus. The gas chromatography-mass spectrometry analysis indicated that 9,10- anthraquinone was the main product of anthracene transformed by laccase from T. versicolor. Microtox test results showed that both anthracene and its laccase-transformation products were not acute toxic compounds, suggesting that laccase-treatment of anthracene would not increase the acute toxicity of contaminated site.展开更多
文摘Cyanobacteria is one of the major sources of toxins in freshwater. These microorganisms are highly adaptive to changing environmental conditions. In this study, the occurrence of toxin producing cyanobacteria in Laguna de Bay and factors affecting its occurrence and growth were determined. The presence ofMicrocystis aeruginosa was positively correlated with nitrate (NO3) and iron (Fe^2+) with correlation coefficient of +0.72972 and +0.91063, respectively. It is negatively correlated with occurrence of sunshine (in days) and turbidity with correlation -0.79055 and -0.93531, respectively.
基金Supported by the National High-Tech R&D Program of China(No.2007AA061101)the Key Laboratory of Soil Environment and Pollution Remediation,Institute of Soil Science,Chinese Academy of Sciencesthe Zhejiang Provincial Natural Science Foundation of China(No.Y5110147)
文摘The transformation profiles of polycyclic aromatic hydrocarbons (PAHs) by pure laccases from Trametes versicolor and Pycnoporus sanguineus, and the optimal reaction conditions (acetonitrile concentration, pH, temperature and incubation time) were determined. Anthracene was the most transformable PAH by both laccases, followed by benzo[a]pyrene, and benzo[a]anthracene. Laccase-mediator system (LMS) could not only improve the PAH oxidation but also extend the substrate types compared to laccase alone. 5e/0 or 10~ (v/v) of acetonitrile concentration, pH 4, temperature of 40 ~C, and incubation time of 24 h were most favorable for anthracene oxidation by laccase from T. versicolor or P. sanguineus. The gas chromatography-mass spectrometry analysis indicated that 9,10- anthraquinone was the main product of anthracene transformed by laccase from T. versicolor. Microtox test results showed that both anthracene and its laccase-transformation products were not acute toxic compounds, suggesting that laccase-treatment of anthracene would not increase the acute toxicity of contaminated site.