title: Control of nitrogen behaviour by phosphate concentration during microalgal-bacterial cultivation using digestate.
abstract: The cultivation of microalgae with digestate supernatant is a promising process for the recovery of mineralized nutrients (P, N) from anaerobic digestion. Nevertheless, the variability of phosphorus concentration in the influent could limit this process. The impact of initial N:P ratios between 3 and 76gNgP(-1) was studied and proved no growth limitation over 14-day batch experiments even when P was depleted. Nitrogen assimilation was not affected by phosphorus concentrations and reached 10.1mgNL(-1)d(-1) whereas phosphorus removal ranged from 0.6 to 2.0mgPL(-1)d(-1). The biomass N:P ratio was found to be a function of the influent N:P ratio. Phosphorus storage by microalgae was thus confirmed. Nitrification was found to be highly dependent on the initial phosphorus concentration. The evolution of microalgae communities was also monitored and revealed the advantage of Scenedesmus over Chlorella when the media was phosphorus-depleted.
authors.affiliation: Irstea, UR GERE, 17 av. de Cucillé, CS 64427, F-35044 Rennes, France; Université Européenne de Bretagne, F-35044 Rennes, France.
authors.forename: Cyril
authors.initials: C
authors.lastname: Marcilhac
authors.affiliation: INRA, UR50, Laboratoire de Biotechnologie de l'Environnement, Avenue des Etangs, F-11100 Narbonne, France.
authors.forename: Bruno
authors.initials: B
authors.lastname: Sialve
authors.affiliation: Irstea, UR GERE, 17 av. de Cucillé, CS 64427, F-35044 Rennes, France; Université Européenne de Bretagne, F-35044 Rennes, France.
authors.forename: Anne-Marie
authors.initials: AM
authors.lastname: Pourcher
authors.affiliation: Irstea, UR GERE, 17 av. de Cucillé, CS 64427, F-35044 Rennes, France.
authors.forename: Christine
authors.initials: C
authors.lastname: Ziebal
authors.affiliation: INRA, UR50, Laboratoire de Biotechnologie de l'Environnement, Avenue des Etangs, F-11100 Narbonne, France.
authors.forename: Nicolas
authors.initials: N
authors.lastname: Bernet
authors.affiliation: Irstea, UR GERE, 17 av. de Cucillé, CS 64427, F-35044 Rennes, France; Université Européenne de Bretagne, F-35044 Rennes, France. Electronic address: fabrice.beline@irstea.fr.
authors.forename: Fabrice
authors.initials: F
authors.lastname: Béline
mesh_terms: D017756:Aquaculture / Q000379:methods*; D018533:Biomass; D002708:Chlorella / Q000254:growth & development; D058086:Microalgae / Q000254:growth & development* / Q000378:metabolism; D058465:Nitrification; D009584:Nitrogen / Q000378:metabolism*; D010710:Phosphates / Q000378:metabolism*; D010758:Phosphorus / Q000378:metabolism; D044444:Scenedesmus / Q000254:growth & development* / Q000378:metabolism; D013045:Species Specificity
chemical_list: D010710:Phosphates; D010758:Phosphorus; D009584:Nitrogen
keywords: Community evolution; Digestate; Microalgae; Nitrification; Phosphorus