Algae, especially microalgae and macroalgae, are photosynthetic organisms that have been used for environmental purposes for a long time, which has been covered in depth through research. The major environmental uses of wastewater treatment, including nutrient recovery and reduction of the organic load, are mentioned in the literature. Microalgae are characterized by a very rapid growth, a huge potential to assimilate nitrogen and phosphorus, and an ability to form symbiotic relationships with other microorganisms, whereas macroalgae are mainly recognized for their high biomass production and their capacity to absorb pollutants in the water environment. This review paper has adopted the PRISMA method to strictly select research papers on biological consortia of the following: microalgae, bacteria, microalgae–fungi, macroalgae, bacteria, and macroalgae–fungi. Assessment of the chosen articles indicates that the cohabitation of microalgae and bacteria is the most favored theme in the literature by far, given its well-documented effectiveness and biological stability. In addition, bibliometric analyses show that there has been increasing attention to microalgae–fungi consortia since 2015, indicating new trends towards biofloc formation, which greatly facilitates biomass separation. On the other hand, consortia involving macroalgae in association with microorganisms (either bacteria or fungi) are still in their infancy in research.
Charef et al. (Sun,) studied this question.