Chlorella vulgaris was cultivated in varying proportions of toxic sludge extracts obtained from a sequencing batch reactor for treating synthetic wastewater containing chlorophenols. C. vulgaris could reduce the ecotoxicity from sludge extracts, and a positive correlation was noted between ecotoxicity removal and total organic carbon removal. In terms of cell density, the optimal proportion of sludge extracts required for the cultivation of C. vulgaris was lower than 50%. The correlation between protein content in per 106 algae and inhibition extent of ecotoxicity of the 5 groups on the day of inoculation (0.9182, p <.05) indicated a positive relationship between algal protein secretion and ecotoxicity. According to the protein expression and differential protein expression analysis, we concluded that C. vulgaris produced proteins that involved in the stress response/redox system and energy metabolism/biosynthesis to respond to the toxic environment and some other proteins related to mixotrophic metabolism.
Bibliographical noteFunding Information:
This work was supported by the Shanghai Pujiang Program in China [Grant No. 13PJD009 ]; the Natural Science Foundation of China [Grant No. 51378207 ] and the National Science and Technology Major Project of the Ministry of Science and Technology of China (Grant No. 2014ZX07202-011-002 ). The authors also would like to express their appreciation to Chinese Scholarship Council (CSC). Appendix A
- Chlorella vulgaris
- Excess sludge
- Proteomics analysis
- Response mechanism
- Toxicity removal