TITLE:
Growth Enhancement of Dunaliella salina by Microbubble Induced Airlift Loop Bioreactor (ALB)—The Relation between Mass Transfer and Growth Rate
AUTHORS:
Kezhen Ying, Daniel J. Gilmour, Yuzhen Shi, William B. Zimmerman
KEYWORDS:
Airlift Bioreactor; Fluidic Oscillator; Dunaliella salina; Specific Growth Rate
JOURNAL NAME:
Journal of Biomaterials and Nanobiotechnology,
Vol.4 No.2A,
April
17,
2013
ABSTRACT:
The efficiency of a novel microalgal culture
system (an airlift loop bioreactor [ALB] engaged with a fluidic oscillator to produce microbubbles) is compared with both a conventional
ALB (producing fine bubbles without the fluidic oscillator) and non-aerated
flask culture. The impact of CO2 mass transfer on Dunaliella salina growth is assessed, through
varying the gas (5% CO2,
95% N2) dosing flow rate. The results showed that approximately 6 - 8 times higher chlorophyll content was
achieved in the aerated ALB cultures than in the non-aerated flasks, and there was
a 20% - 40% increase in specific growth rate of D. salina in the novel ALB with microbubbles when compared with the
conventional ALB cultures.
The increase in chlorophyll content was found to be proportional to the total amount
of CO2 mass transfer. For the same dosing time and flow rate, higher
CO2 mass transfer rate (microbubble dosing) resulted in a greater growth
rate.