Moreover, both the clostridial strain and the mixed cultures were chosen by their ability to produce bioH2 directly from starch without the need of a prior
saccharification step. This strategy was already successfully
employed in the production of H2 by clostridial strains from complex feedstock containing starch, like palm oil mill effluents [38],
and from raw starch [39]. The concentration of microalgal biomass
ranged from 10 to 50 g/L and its sugar concentration is determinant for the bioconversion yield. The sugar content of the microalgal biomass achieved 18% of the total algal dry mass. This value is
in accordance with the sugar concentration range described for S.
obliquus (10–17% (w/w))