Numerous researches reported that some filamentous fungi
that naturally existed in activated sludge could immobilize or entrap
the sludge solids by forming bio-flocculation/coagulation
and strengthen the flocculation structure due to their unique filamentous
properties [10,14,15]. Therefore in this study, filamentous
fungi were identified and isolated from local municipal wastewater
sludge and used to evaluate their feasibility for bio-flocculation of
a non-flocculating microalgae strain Chlorella vulgaris UMN235.
Self-pelletization under optimized culture conditions was developed
and evaluated as a promising alternative to current harvesting
technologies. Furthermore, the lipid content of some fungi
species was reported to be over 30% of total fungal biomass [11],
making high oil fungi a good biodiesel feedstock, which could be
converted into biofuels directly together with oleaginous microalgae.
Therefore, the lipid content of fungi is also an important selection
criterion.