Dynamic mechanism of the microbiota of high-salinity organic wastewater with salt-tolerant yeast and its application

Abstract

High-salinity organic wastewater represents an industrial wastewater with complex composition and poor biodegradability, which is difficult to treat biochemically. To reveal the intrinsic mechanism of the microbial community of the high-salinity organic wastewater treated with salt-tolerant yeast, the microbiota and the environmental factor were characterized and investigated. As a result of bioaugmentation, the removal rates of chemical oxygen demand, NH3–H, and total nitrogen increased significantly in a pilot-scale wastewater treatment plant. The result of high-throughput sequencing showed that microbial community structure was significantly affected by bioaugmentation. At the phylum level, Proteobacteria and Ascomycota were dominant, whereas at the genus level, Paracoccus and Meyerozyma were dominant. Meyerozyma successfully colonized and played a key role in the treatment of high-salinity organic wastewater, which might be the main reason leading to the increase of pollutant removal efficiency. Furthermore, pH, dissolved oxygen, and water inflow were the key factors affecting microbial community succession during bioaugmentation, however, the abundance of Meyerozyma was not affected by the concentration of influent contaminants. This study systematically revealed the dynamic change and functional prediction of microbial during bioaugmentation, as well as the relationship between microbial community and environmental factors, which laid a solid theoretical foundation for the subsequent large-scale high-salinity wastewater treatment.