title: Mixotrophic growth of Phaeodactylum tricornutum on fructose and glycerol in fed-batch and semi-continuous modes.
abstract: Mixotrophic cultures of Phaeodactylum tricornutum were carried out in bubble columns using fructose and glycerol in indoor fed-batch and semi-continuous modes. In the fed-batch cultures, different nutrient-addition strategies, combined with stepwise increments in the light intensity, were assayed. It was found that glycerol promoted significantly higher biomass productivity than fructose. A glycerol-induced photoinhibition that arrested the growth of P. tricornutun was also observed. As this was considered a limitation as regards transferring the fed-batch mode to outdoor conditions, this information was used to culture P. tricornutum in semi-continuous mode. Similar glycerol-induced photoinhibition was not observed in these cultures, even at highest dilution rates. Although the highest biomass (1.5 g L(-1) d(-1)) and EPA (40 mg L(-1) d(-1)) productivities found in the semi-continuous cultures were lower than those obtained photoautotrophically in outdoor photobioreactors, the findings showed that semi-continuous mode was an excellent candidate for transferring mixotrophic culture to an outdoor setting.
authors.affiliation: Area of Chemical Engineering, Department of Engineering, University of Almería, 04120 Almería, Spain.
authors.forename: M C
authors.initials: MC
authors.lastname: Cerón-García
authors.affiliation: Area of Chemical Engineering, Department of Engineering, University of Almería, 04120 Almería, Spain.
authors.forename: J M
authors.initials: JM
authors.lastname: Fernández-Sevilla
authors.affiliation: Area of Chemical Engineering, Department of Engineering, University of Almería, 04120 Almería, Spain.
authors.forename: A
authors.initials: A
authors.lastname: Sánchez-Mirón
authors.affiliation: Area of Chemical Engineering, Department of Engineering, University of Almería, 04120 Almería, Spain.
authors.forename: F
authors.initials: F
authors.lastname: García-Camacho
authors.affiliation: Area of Chemical Engineering, Department of Engineering, University of Almería, 04120 Almería, Spain. Electronic address: acontre@ual.es.
authors.forename: A
authors.initials: A
authors.lastname: Contreras-Gómez
authors.affiliation: Area of Chemical Engineering, Department of Engineering, University of Almería, 04120 Almería, Spain.
authors.forename: E
authors.initials: E
authors.lastname: Molina-Grima
mesh_terms: D018533:Biomass; D017377:Diatoms / Q000254:growth & development* / Q000378:metabolism; D005632:Fructose / Q000378:metabolism*; D005990:Glycerol / Q000378:metabolism*
chemical_list: D005632:Fructose; D005990:Glycerol
keywords: Fed-batch; Glycerol; Microalgae; Mixotrophic growth; Semi-continuous