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

Abstract

A Chlorella sp.-Cupriavidus necator (C. necator) consortium was artificially established for phenol degradation. The synergistic 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 consortium 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 ℃ and a pH in the range of 5.5-7.5. Under optimal conditions, this consortium could degrade phenol with a maximum concentration of 1200 mg L -1 within 60 h. Comparative transcriptomic analysis was conducted to discuss the symbiosis mechanism of this consortium 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, which, we suggest, may be the main reason for their mutual promotion of growth and phenol degradation.

Effect of co-culture with Halomonas mongoliensis on Dunaliella salina growth and phenol degradation

“…Many reports have been demonstrated that co-culture of microalgae and bacteria enhanced the phenol degradation and improved the biomass of microalgae. Yi et al (2020) reported that Chlorella sp. monoculture could not degrade 400 mg L −1 phenol, and its growth was seriously inhibited.…”