(68c) Optimization of Microalgal Oxygen Evolution within Planar Cultivation Systems

Optimization
of microalgal oxygen evolution within planar cultivation systems

Sina Kaabipour¹, Julia
Lin¹, Clayton Jeffryes^1,*

¹Nanobiomaterials and Bioprocessing
Laboratory (NABLAB), Dan F. Smith Department of Chemical Engineering, Lamar
University, Beaumont, TX 77710

*Corresponding Author:
cjeffryes@lamar.edu

Algal bioprocesses have exhibited
diverse applications ranging from production of biofuels to pharmaceutical
compounds for novel drug manufacture [1]. The significance of biogenic oxygen
evolution however lies in maintaining efficient biomass productivity such as within
photobioreactors [2] and hybrid ecosystems [3]. The following analysis
investigates the effect of microalgal cell culture concentration on the biogenic
oxygen generation by considering the principles of light penetration. A dimensionless
model was obtained from illumination and specific physiologically-related
parameters to describe the oxygen production rate of Chlorella Vulgaris and
Synechococcus elongatus.
Such parameters were optimized to yield a satisfactory fit between experimental
oxygen generation data and model output. Furthermore, the optimal dimensionless
concentration of each strain was specified with respect to different light
inputs followed by the determination of optimal average volumetric productivity.
The results express that the evolution rate can be optimized within any planar tissue
culture regardless of the strain type and system dimensions. This is beneficial
in utilizing synergistic phototrophic-heterotrophic microenvironments where preserving
the balance between bacterial respiration and photosynthetic production is of
crucial importance, which can concordantly result in prohibition of unbalanced
population ratios and profligate growth of one species [3]. Further applications
contribute to effective biotransformation of high value compounds [4],
environmental remediation [5], and renewable energy [6]. Moreover, the
presented model yields a less intricate approach for understanding bioprocess
variables useful for describing processes with various types of strains, tissue
cultures and cultivation systems.

Keywords: Chlorella
Vulgaris, Dimensionless Equations, Optimization

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