An efficient Chlorella sp.-Cupriavidus necator microcosm for phenol degradation and its cooperation mechanism

Tao Yi; Ying Shan; Bo Huang; Tao Tang; Wei Wei; Nigel W T Quinn

doi:10.1016/j.scitotenv.2020.140775

An efficient Chlorella sp.-Cupriavidus necator microcosm for phenol degradation and its cooperation mechanism

Sci Total Environ. 2020 Nov 15:743:140775. doi: 10.1016/j.scitotenv.2020.140775. Epub 2020 Jul 6.

Authors

Tao Yi¹, Ying Shan², Bo Huang², Tao Tang³, Wei Wei⁴, Nigel W T Quinn⁵

Affiliations

¹ CAS Key Lab of Low-Carbon Conversion Science & Engineering, Shanghai Advanced Research Institute, Chinese Academy of Sciences, Shanghai 201210, China; School of Life Sciences, Shanghai University, Shanghai 200444, China.
² CAS Key Lab of Low-Carbon Conversion Science & Engineering, Shanghai Advanced Research Institute, Chinese Academy of Sciences, Shanghai 201210, China.
³ CAS Key Lab of Low-Carbon Conversion Science & Engineering, Shanghai Advanced Research Institute, Chinese Academy of Sciences, Shanghai 201210, China; Earth Science Division, Lawrence Berkeley National Laboratory, California 94720, USA. Electronic address: tangt@sari.ac.cn.
⁴ CAS Key Lab of Low-Carbon Conversion Science & Engineering, Shanghai Advanced Research Institute, Chinese Academy of Sciences, Shanghai 201210, China; Center for Excellence in Urban Atmospheric Environment, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China.
⁵ Earth Science Division, Lawrence Berkeley National Laboratory, California 94720, USA.

PMID: 32663680
DOI: 10.1016/j.scitotenv.2020.140775

Abstract

A Chlorella sp.-Cupriavidus necator (C. necator) microcosm was artificially established for phenol degradation. The cooperation relationship between Chlorella sp. and C. necator was initially demonstrated, and then the effects of Chlorella sp./C. necator inoculation ratio, light intensity, temperature and pH on the performance of this microcosm were systematically evaluated and optimized. The optimal conditions for phenol degradation were as follows: a Chlorella sp./C. necator inoculation ratio of 1:1, a light intensity of 110 μmol m^-2 s^-1, a temperature in the range of 25-32 °C and a pH in the range of 5.5-7.5. Under optimal conditions, this microcosm could degrade phenol with a maximum concentration of 1200 mg L^-1 within 60 h. It was found that only when the phenol concentration was reduced to the tolerance concentration of microalgae, that is, the last stage of phenol degradation, the cooperation effect could be generated, indicating that the tolerance of microalgae to phenol may be more important than its degradation performance. Comparative transcriptomic analysis was conducted to discuss the cooperation mechanism of this microcosm subject to high phenol concentrations. The up-regulation of genes involved in photosynthesis and carbon fixation of Chlorella sp. demonstrated the CO₂ and O₂ exchange between Chlorella sp. and C. necator and their cooperation relationship. This study suggests that this microcosm has great potential for the bioremediation of phenol contaminants.

Keywords: Biodegradation; Comparative transcriptomic analysis; Cooperation relationship; Microalgal-bacterial microcosm; Phenol.

MeSH terms

Biomass
Chlorella*
Cupriavidus necator*
Microalgae*
Phenol
Phenols

Substances

Phenols
Phenol