n research by Aravindan Rajendran and Bo Hu published recently in Biotechnology for Biofuels, they describe the development of a novel platform technology using algae and fungal cultures. While microalgae is considered a promising source for biofuel and bioenergy production, bio-remediation and production of high-value bioactive compounds, harvesting microalgae remains a major bottleneck in the algae-based processes.
The objective of Drs. Rajendran and Hu’s research was to mimic the growth of natural lichen and develop a novel biofilm platform technology using filamentous fungi and microalgae to form a lichen type of biofilm “mycoalgae” in a supporting polymer matrix.
The possibility of the co-existence of Chlorella vulgaris with various fungal cultures was tested to identify the best strain combination for high algae harvest efficiency. The effect of different matrices for cell attachment and biofilm formation, cell surface characterization of mycoalgae biofilm, kinetics of the process with respect to the algae-fungi cell distribution and total biomass production was studied.
Mycoalgae biofilm with algae attachment efficiency of 99.0% and above was achieved in a polymer-cotton composite matrix with glucose concentration of 2 g/L in the growth medium and agitation intensity of 150 rpm at 27 °C. The total biomass in the co-culture with the selected strain combination (Mucor sp. and Chlorella sp.) was higher than the axenic cultures of fungi and algae at the conditions tested.
The results show that algae can be grown with complete attachment to a bio-augmenting fungal surface and can be harvested readily as a biofilm for product extraction from biomass. Even though, interaction between heterotrophic fungi and phototrophic algae was investigated in solid media after prolonged contact in a report, this research is the first of its kind in developing an artificial lichen type biofilm called “mycoalgae” biofilm completely attached on a matrix in liquid cultures.
The mycoalgae biofilm based processes, propounds the scope for exploring new avenues in the bio-production industry and bioremediation.