Effect of aeration in simple photobioreactor system for biomass production of synechococcus sp. (cyanobacteria) HS-7 and HS-9 as biofuel feedstock

¹ Department of Biology, Faculty of Mathematics and Natural Sciences, Universitas Indonesia, Kampus UI Depok, Depok 16424, West Java, Indonesia
² Department of Mechanical Engineering, Faculty of Engineering, Universitas Indonesia, Kampus UI Depok, Depok 16424, West Java, Indonesia

^* Coresponding author: nining.prihantini@gmail.com

Abstract

People have been searching toward to biofuel as a prominent alternative to replace oil fuel. Microalgae biomass, specifically from the genus Synechococcus, has been used as the biofuel’s feedstock as it’s able to grow faster than the other groups at cyanobacteria. Strains being used were isolated from Ciseeng hot spring (HS-7) and Rawa Danau Banten hot spring (HS-9). The intensity of aeration (IA) were given as high (330 bubbles/min) and low (220 bubbles/min) to understand its influence on feedstock growth. Change in growth was observed microscopically using direct methods over fourteen days. At the end of the experiment, result demonstrate that high IA gaves rise to Synechococcus biomass density at 125,21 × 10₆ cell/ml and 100,63 × 10⁶ cell/ml for HS-7 & HS-9 respectively. Meanwhile, low IA gaves rise to Synechococcus biomass density at 21,7 × 10⁶ cell/ml and 10,61 × 10⁶ cell/ml for HS-7 & HS-9 accordingly. Positive trend also follows the growth at Synechococcus biomass with high IA, but did not apply to the system with low IA. The difference in biomass production occurred because of discrepancies in cell and nutrient distribution inside the photobioreactor system. Therefore, it implies that proper controlling of IA would affect the yielding of feedstock for producing biofuels.