Cold-adapted culturing of the microalga Monoraphidium sp. in thin-layer raceway pond for biomass production
Abstrakt
Three cultivation regimes were tested in cold-adapted cultures of the green microalga Monoraphidium in an outdoor thin-layer raceway pond: cultivation under sunlight; its combination with continuous supplementary illumination; and nitrogen depletion using both light sources. The highest volumetric and areal productivity, 0.16 g L-1 d-1 and 3.22 g m- 2 d-1, respectively corresponding to the specific growth rate mu of 0.191 d-1 were achieved when sunlight was combined with supplementary illumination.
The maximum total fatty acid content, 20.29 % of DW, rich in oleic acid, 54 % of total fatty acid content, was achieved under nitrogen depletion stress. An outstanding amount of lutein, 26.39 mg lutein g-1 DW, was detected grown under sunlight in the first trial.
From the harvested and fermented biomass in the second trial 236 mLN g- 1oTS of methane was generated.