Application of agar liquid-gel transition in cultivation and harvesting of microalgae for biodiesel production

In order to increase microalgal biomass productivity efficient cultivation and harvesting methods are needed against the available traditional methods. The present study focuses on the same by harvesting microalgae using agar gel. Agar medium containing bold's basal medium (BBM) undergoes a thermore-versible gel transition. As compared to the traditional protocols, this gel is used to cultivate microalgae without even affecting the total productivity. To develop the gel for microalgae cultivation, agar was boiled in BBM. Then the agar was cooled to 35 degrees C and microalgae culture was added to it. After seeding the microalgae the temperature of the agar was further decreased by 10 degrees C to induce gelation. Instead of isolated cells microalgae were grown in clusters within the agar gel. Microalgal clusters gravimetrically settle at the bottom within 2 h. In this method agar can be reused. (C) 2017 Elsevier Ltd. All rights reserved.