An optimisation approach for culturing shear-sensitive dinoflagellate microalgae in bench-scale bubble column photobioreactors.
The dinoflagellate Karlodinium veneficum was grown in bubble column photobioreactors and a genetic algorithm-based stochastic search strategy used to find optimal values for the culture parameters gas flow rate, culture height, and nozzle sparger diameter. Cell production, concentration of reactive oxygen species (ROS), membrane fluidity and photosynthetic efficiency were studied throughout the culture period. Gas-flow rates below 0.26Lmin(-1), culture heights over 1.25m and a nozzle diameter of 1.5mm were found to provide the optimal conditions for cell growth, with an increase of 60% in cell production with respect to the control culture. Non-optimal conditions produced a sufficiently high shear stress to negatively affect cell growth and even produce cell death. Cell physiology was also severely affected in stressed cultures. The production of ROS increased by up to 200%, whereas cell membrane fluidity decreased by 60% relative to control cultures. Photosynthetic efficiency decreased concomitantly with membrane fluidity.
Chemical Engineering Area, University of Almería, 04120 Almería, Spain. Electronic address: llr288@ual.es.
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L
López-Rosales
Chemical Engineering Area, University of Almería, 04120 Almería, Spain.
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F
García-Camacho
Chemical Engineering Area, University of Almería, 04120 Almería, Spain.
A
A
Sánchez-Mirón
Chemical Engineering Area, University of Almería, 04120 Almería, Spain.
A
A
Contreras-Gómez
Chemical Engineering Area, University of Almería, 04120 Almería, Spain.
E
E
Molina-Grima
D001709:Biotechnology / Q000295:instrumentation / Q000379:methods; D002462:Cell Membrane / Q000378:metabolism; D004141:Dinoflagellida / Q000254:growth & development* / Q000378:metabolism; D058086:Microalgae / Q000254:growth & development* / Q000378:metabolism; D008962:Models, Theoretical; D058433:Photobioreactors; D010788:Photosynthesis; D017382:Reactive Oxygen Species / Q000378:metabolism; D033081:Shear Strength
D017382:Reactive Oxygen Species
Dinoflagellate; Fluid-dynamics; Karlodinium veneficum; Microalgae; Physiology