title: Use of fermentative metabolites for heterotrophic microalgae growth: Yields and kinetics.
abstract: The growth of two lipid-producing Chlorella species on fermentative end-products acetate, butyrate and lactate, was investigated using a kinetic modeling approach. Chlorella sorokiniana and Auxenochlorella protothecoides were grown on synthetic media with various (acetate:butyrate:lactate) ratios. Both species assimilated efficiently acetate and butyrate with yields between 0.4 and 0.5g carbon of biomass/g carbon of substrate, but did not use lactate. The highest growth rate on acetate, 2.23d(-1), was observed for C. sorokiniana, and on butyrate, 0.22d(-1), for A. protothecoides. Butyrate removal started after complete acetate exhaustion (diauxic effect). However, butyrate consumption may be favored by the increase of biomass concentration induced by the initial use of acetate. A model combining Monod and Haldane functions was then built and fitted the experimental data well for both species. Butyrate concentration and (acetate:butyrate) ratios were identified as key parameters for heterotrophic growth of microalgae on fermentative metabolites.
authors.affiliation: INRA, UMR 050, Laboratoire de Biotechnologie de l'Environnement, Avenue des Etangs, 11100 Narbonne, France.
authors.forename: V
authors.initials: V
authors.lastname: Turon
authors.affiliation: INRA, UMR 050, Laboratoire de Biotechnologie de l'Environnement, Avenue des Etangs, 11100 Narbonne, France.
authors.forename: C
authors.initials: C
authors.lastname: Baroukh
authors.affiliation: INRA, UMR 050, Laboratoire de Biotechnologie de l'Environnement, Avenue des Etangs, 11100 Narbonne, France.
authors.forename: E
authors.initials: E
authors.lastname: Trably
authors.affiliation: INRA, UMR 050, Laboratoire de Biotechnologie de l'Environnement, Avenue des Etangs, 11100 Narbonne, France.
authors.forename: E
authors.initials: E
authors.lastname: Latrille
authors.affiliation: Laboratoire Ecologie des Systèmes Marins Côtiers-UMR 5119, 2 Rue des Chantiers, 34200 Sète, France.
authors.forename: E
authors.initials: E
authors.lastname: Fouilland
authors.affiliation: INRA, UMR 050, Laboratoire de Biotechnologie de l'Environnement, Avenue des Etangs, 11100 Narbonne, France. Electronic address: Jean-Philippe.Steyer@supagro.inra.fr.
authors.forename: J-P
authors.initials: JP
authors.lastname: Steyer
mesh_terms: D000085:Acetates / Q000494:pharmacology; D018533:Biomass; D020148:Butyric Acid / Q000494:pharmacology; D002244:Carbon / Q000494:pharmacology; D002245:Carbon Dioxide / Q000378:metabolism; D002708:Chlorella / Q000187:drug effects / Q000254:growth & development* / Q000378:metabolism; D005285:Fermentation / Q000187:drug effects; D052836:Heterotrophic Processes / Q000187:drug effects; D007700:Kinetics; D019344:Lactic Acid / Q000494:pharmacology; D008055:Lipids / Q000494:pharmacology; D055442:Metabolome / Q000187:drug effects; D058086:Microalgae / Q000187:drug effects / Q000254:growth & development* / Q000378:metabolism
chemical_list: D000085:Acetates; D008055:Lipids; D020148:Butyric Acid; D002245:Carbon Dioxide; D019344:Lactic Acid; D002244:Carbon
keywords: Chlorella; Diauxic effect; Heterotrophy; Kinetic model; Volatile fatty acids