Enhanced lipidic algae biomass production using gas transfer from a fermentative Rhodosporidium toruloides culture to an autotrophic Chlorella protothecoides culture

• Published in: Bioresource technology Vol. 138; pp. 48 - 54
• Main Authors: Santos, C.A., Caldeira, M.L., Lopes da Silva, T., Novais, J.M., Reis, A.
• Format: Journal Article
• Language: English
• Published: Kidlington Elsevier Ltd 01-06-2013; Elsevier
• Subjects: Algae; Ammonium Compounds - metabolism; Autotrophic Processes; Basidiomycota - growth & development; Basidiomycota - metabolism; Biodiesel; Biofuel production; Biological and medical sciences; Biomass; Biotechnology; Carbon Dioxide - metabolism; Carbon dioxide fixation; Cell Culture Techniques; Cell Membrane - metabolism; Chlorella - growth & development; Chlorella protothecoides; Culture; Energy; Fatty Acids - metabolism; Fermentation; Flow Cytometry; Fundamental and applied biological sciences. Psychology; Gases - metabolism; Glucose - metabolism; Heterotrophic Processes; Hydrogen-Ion Concentration; Industrial applications and implications. Economical aspects; Kinetics; Lipid; Lipids - chemistry; Metabolism; Methods. Procedures. Technologies; Microalga; Microbial engineering. Fermentation and microbial culture technology; Natural gas; Oxygen - metabolism; Photobioreactors - microbiology; Photosynthesis; Reactors; Respiration; Rhodosporidium toruloides; Time Factors; Yeast; Carbon dioxide fixation; Yeast; Microalga; Biodiesel; Lipid; Chlorella; Algae; Carbon dioxide; Lipids; Autotrophy; Biomass; Chlorophyceae; Fermentation; Basidiomycota; Fungi; Fixation; Chlorophyta; Alga; Microorganism; Rhodosporidium toruloides
• ISSN: 0960-8524; 1873-2976
• DOI: 10.1016/j.biortech.2013.03.135

•Efficient symbiotic system between yeast and microalgae cultures.•Improvement of microalga growth.•Efficient CO2 fixation by C. protothecoides.•Fatty acids source suitable to produce biodiesel.•The association of bioreactors is a feasible way to supply CO2 to algae culture.
In order to produce single-cell oil for biodiesel, a yeast and a microalga were, for the first time, grown in two separate reactors connected by their gas-phases, taking advantage of their complementary nutritional metabolisms, i.e., respiration and photosynthesis.
The yeast Rhodosporidium toruloides was used for lipid production, originating a carbon dioxide-enriched outlet gas stream which in turn was used to stimulate the autotrophic growth of Chlorella protothecoides in a vertical-alveolar-panel (VAP) photobioreactor.
The microalgal biomass productivity was 0.015gL−1h−1, and its lipid productivity attained 2.2mgL−1h−1 when aerated with the outlet gas stream from the yeast fermenter. These values represent an increase of 94% and 87%, respectively, as compared to a control culture aerated with air.
The CO2 bio-fixed by the microalgal biomass reached an estimated value of 29mgL−1h−1 in the VAP receiving the gas stream from the fermenter, a value 1.9 times higher than that measured in the control VAP.