Stacked optical waveguide photobioreactor for high density algal cultures

Area of Science:

• Biotechnology
• Algal cultivation
• Photobioreactor design

Background:

• Traditional photobioreactors suffer from poor light distribution due to self-shading, limiting volumetric productivity.
• Optimizing light distribution is crucial for efficient algal cultivation and biomass production.

Purpose of the Study:

• To introduce an ultracompact algal photobioreactor design that enhances light distribution.
• To evaluate the performance of the novel photobioreactor in terms of biomass growth and productivity.
• To demonstrate sustained production of a target compound using the engineered system.

Main Methods:

• Incorporation of stacked layers of slab waveguides with embedded light scatterers.
• Operation and optimization of a 10-layer bioreactor.
• Cultivation of a genetically engineered algal strain for compound secretion.

Main Results:

• Sustained uniform biomass growth for 3 weeks in the 10-layer bioreactor.
• Demonstrated an 8-fold increase in biomass productivity compared to traditional systems.
• Achieved constant secreted ethylene production for over 45 days.

Conclusions:

• The stacked waveguide architecture significantly improves light distribution in photobioreactors.
• The novel design leads to enhanced biomass productivity and reduced need for culture mixing.
• This technology offers potential for cost reduction in algal cultivation and bioproducts manufacturing.