The roles of bacteria in resource recovery, wastewater treatment and carbon fixation by microalgae-bacteria consortia: A critical review

Microalgae-bacteria consortia (MBCs) with mutualism have attracted much attention due to their advantages in wastewater treatment, resource recovery and CO2 sequestration. To date, most related studies have focused on the overall functions of MBC in the abovementioned processes. In the MBC reported in the literature, there are mainly three types of bacteria, i.e., 1) bacteria naturally associated with microalgae; 2) bacteria in activated sludge; and 3) bacteria with known identities. However, the effects of different bacterial sources and strains on MBC performance have not been compared. Therefore, this review summarizes the various types of MBC, the relationships between microalgae and bacteria, the effects of different bacteria on growth, pigment and lipid production, pollutant removal, and carbon fixation by MBC. In addition, the remaining research gaps and future perspectives in this field are proposed. This review may act as a guide to the selection of bacteria in establishing more robust MBC and promote their applications in pollution remediation and greenhouse gas reduction.