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.

Recent Advances in the Research on the Anticyanobacterial Effects and Biodegradation Mechanisms of Microcystis aeruginosa with Microorganisms

“…AF-1 (cell-free filtrate) was lower than that of the control at the first 48 h but much higher at 72 h, indicating that some evasive mechanisms were taken to prevent the ROS accumulation in cyanobacterial cells at the initial stage [51]. Similar variations of ROS have been observed in M. aeruginosa KW after being treated with Paucibacter aquatile DH15, and the malondialdehyde (MDA) content and SOD activity related to remove ROS also increased at first and then decreased [61]; The MDA content, CAT and POD activity of M. aeruginosa FACHB-905 also increased quickly when fermentation liquid (5%, v/v) of P. aeruginosa [18] and P. chrysosporium was added quickly [101]; moreover, the responses of M. aeruginosa FACHB-905 cells to Streptomyces sp. KY-34 and Streptomyces sp.…”

“…It has been reported that the fungus Trichaptum abietinum 1302BG can eliminate four cyanobacteria directly including M. aeruginosa FACH-918 and M. aeruginosa PCC 7806 in 48 h [106]. Some other fungi such as Trichoderma citrinoviride [6], Penicillium chrysogenum [97], Aureobasidium pullulans KKUY070 [98], Lopharia spadicea [99], Phanerochaete chrysosporium [100,101], Irpex lacteus T2b [102], Trametes versicolor F21a [107] and Bjerkandera adusta T1 [103] also show good inhibitory activities against M. aeruginosa. It has been stated that T. citrinoviride and A. pullulans have highly specific anticyanobacterial effects towards Microcystis spp.…”

“…Gene such as mcyB that are involved in microcystins synthesis are also inhibited by Penicillium spp. [97], the white-rot fungi P. chrysosporium [100,101] and P. noxius HN-1 [104]; moreover, both directly attack the anticyanobacterium (S. globisporus G9) [83] and indirectly attack anticyanobacteria (including S. amritsarensis HG-16 and Bacillus sp. AF-1) could inhibit microcystins synthesis [5,51].…”

The Effect of Algicidal and Denitrifying Bacteria on the Vertical Distribution of Cyanobacteria and Nutrients

“…The control and mitigation measures of Microcystis bloom have been developed and highlighted by researchers. Many algicidal bacteria have been isolated [5,6] and constitute the major group of microorganisms showing inhibitory effects on cyanobacteria [7]. Algicidal bacteria, as a biological control method, are expected to be environmentally friendly and feasible for bloom control [8].…”