Characterization and effects of two algicidal isolates on antioxidase activities of Chlorella pyrenoidosa

With increasing water pollution, algal bloom becomes more and more frequent. To manage algal blooms, the exploitation and study of novel algae-lysing strains are extremely urgent. In this study, two algicidal isolates (NP23 and AM11) against Chlorella pyrenoidosa were obtained from the Baiguishan reservoir in China. Phylogenetic analysis of the 16S rDNA sequences revealed that isolates NP23 and AM11 were closely related to Enterobacter cloacae and Gibberella moniliformis, respectively. Moreover, to determine the effects of these two algicidal isolates on antioxidase activities of C. pyrenoidosa, the activities of superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT) were investigated in cultures of their host algae. The results showed that NP23 and AM11 were able to promote the activity of these three antioxidases soon after inoculation (1-3 days) but significantly inhibited antioxidase activities after the third day. These results provide a strong foundation for further research of the algicidal mechanism. (c) 2015 American Institute of Chemical Engineers Environ Prog, 34: 1647-1651, 2015