ARTIFICIAL LICHENS: A POTENTIAL APPROACH TO HARVEST MICROALGAE CELLS

Lichens exist in nature as a dynamic system between fungi and algae or cyanobacteria and their use have been considered one of the new exponents in the field of bioprocess engineering. Multiple research fronts carried out with microalgae have confirmed their promising properties in bioprocesses. A commonly reported bottleneck that hinders their economic feasibility is in harvesting stage. Production operating facilities are hampered by high energy consumption or by use of toxic chemicals, which often results in low biomass rates, increasing the volume of water in the process and requirements for separation, employing conventional harvesting operations. On the other hand, fungal species are easier to recover than microalgae. With appropriate combination (fungi + microalgae) an interaction between fungal hyphae and microalgae cells can be promoted, effectively removing microalgae from cocultures. This work assessed the efficiency of two procedures for microalgae harvesting applying lichens formed between species Chlorella vulgaris (microalgae) and Mucor circinelloides (filamentous fungus), with presence and absence of a matrix. Both strategies afforded high efficient to recover microalgae (>95%), although the best result was found for the strategy using a screen, which resulted in total recovery of 99.7% microalgal biomass and 47% of microalgal biomass in the lichenized structured.