2.1. Culture conditions for the experimental organism
Chlorella minutissima, a fast-growing green microalga, was
selected for this study. Axenic cultures of the test microalga was
maintained in Erlenmeyer flasks with N 11 medium as per Soeder & Bolze
(1981). The temperature was mentained at 25±2 °C with phtoperiod of 14 h
and light intensity of 75 μmol photons m−2s−1 PAR.
For drying experiments, C. minutissima was cultivated in raceway
ponds with volumetric capacity of 40,000 L each (14 × 4 × 0.75 m).
Before cultivation in raceway ponds, the selected microalga was
scaled-up in the UZn medium (Koley, Mathimani, Bagchi, Sonkar, &
Mallick, 2019), and was acclimatized to the outdoor condition as
detailed in Sonkar, Deb, & Mallick (2020). The raceway ponds were
operated at 30 cm of culture depth with a corresponding culture volume
of 16000 L. Harvesting of the microalgal biomass was carried by
pH-induced flocculation using NaOH at pH 12 for 12 h following Koley,
Prasad, Bagchi, & Mallick (2017).