Algicidal Efficiency and Genotoxic Effects of Phanerochaete chrysosporium against Microcystis aeruginosa

Abstract

Eutrophication has become a severe environmental problem. This study evaluated the algicidal efficiency and genotoxic effects of Microcystis aeruginosa co-cultured with Phanerochaete chrysosporium for 48 h under the optimum conditions of 250 mg/L of P. chrysosporium at 25 °C with dissolved oxygen content of 7.0 mg/L. The results showed that the activity of algal dehydrogenase, superoxide dismutase, and peroxidase were all decreased and the malondialdehyde content increased after co-culturing. Fourier transform infrared spectroscopy and scanning electron microscopy observations showed that the functional group and structure of algal cells were significantly changed. Compared with those of control tadpoles, blood cells of Fejervarya multistriata tadpoles had increased micronucleus frequency (from 1.05 ± 0.09 to 1.99 ± 0.05) and abnormal nuclei (from 2.45 ± 0.06 to 5.83 ± 0.07). The tail length of M. aeruginosa co-cultured with P. chrysosporium increased from 1.12 ± 0.21 to 21.68 ± 0.34, and the comet length increased from 6.45 ± 0.09 to 36.45 ± 0.67 within 48 h. Micronucleus assay and Comet assay results demonstrated that P. chrysosporium might effectively remove algae and reduce genotoxic effects and may be safe for aquatic ecosystems.