title: Dissolved inorganic carbon enhanced growth, nutrient uptake, and lipid accumulation in wastewater grown microalgal biofilms.
abstract: Microalgal biofilms grown to evaluate potential nutrient removal options for wastewaters and feedstock for biofuels production were studied to determine the influence of bicarbonate amendment on their growth, nutrient uptake capacity, and lipid accumulation after nitrogen starvation. No significant differences in growth rates, nutrient removal, or lipid accumulation were observed in the algal biofilms with or without bicarbonate amendment. The biofilms possibly did not experience carbon-limited conditions because of the large reservoir of dissolved inorganic carbon in the medium. However, an increase in photosynthetic rates was observed in algal biofilms amended with bicarbonate. The influence of bicarbonate on photosynthetic and respiration rates was especially noticeable in biofilms that experienced nitrogen stress. Medium nitrogen depletion was not a suitable stimulant for lipid production in the algal biofilms and as such, focus should be directed toward optimizing growth and biomass productivities to compensate for the low lipid yields and increase nutrient uptake.
authors.affiliation: Utah State University, Department of Biological Engineering, Logan, UT 84322, United States. Electronic address: maureen.kesaano@aggiemail.usu.edu.
authors.forename: Maureen
authors.initials: M
authors.lastname: Kesaano
authors.affiliation: University of Minnesota, Department of Bioproducts and Biosystems Engineering and West Central Research and Outreach Center, St. Paul, MN 55108, United States.
authors.forename: Robert D
authors.initials: RD
authors.lastname: Gardner
authors.affiliation: Montana State University, Department of Microbiology and Center for Biofilm Engineering, Bozeman, MT 59717, United States.
authors.forename: Karen
authors.initials: K
authors.lastname: Moll
authors.affiliation: Montana State University, Department of Civil Engineering and Center for Biofilm Engineering, Bozeman, MT 59717, United States.
authors.forename: Ellen
authors.initials: E
authors.lastname: Lauchnor
authors.affiliation: Montana State University, Department of Chemical and Biological Engineering and Center for Biofilm Engineering, Bozeman, MT 59717, United States.
authors.forename: Robin
authors.initials: R
authors.lastname: Gerlach
authors.affiliation: Montana State University, Department of Chemical and Biological Engineering and Center for Biofilm Engineering, Bozeman, MT 59717, United States.
authors.forename: Brent M
authors.initials: BM
authors.lastname: Peyton
authors.affiliation: Utah State University, Department of Biological Engineering, Logan, UT 84322, United States.
authors.forename: Ronald C
authors.initials: RC
authors.lastname: Sims
mesh_terms: D001639:Bicarbonates / Q000494:pharmacology; D018441:Biofilms / Q000187:drug effects / Q000254:growth & development*; D056804:Biofuels; D002244:Carbon / Q000378:metabolism*; D050356:Lipid Metabolism; D058086:Microalgae / Q000187:drug effects / Q000254:growth & development / Q000502:physiology*; D009584:Nitrogen / Q000302:isolation & purification; D010100:Oxygen / Q000032:analysis / Q000378:metabolism; D010758:Phosphorus / Q000302:isolation & purification; D010788:Photosynthesis; D014865:Waste Disposal, Fluid / Q000379:methods; D062065:Wastewater; D060753:Water Quality
chemical_list: D001639:Bicarbonates; D056804:Biofuels; D002244:Carbon; D009584:Nitrogen; D010100:Oxygen; D010758:Phosphorus; D062065:Wastewater
keywords: Biofilms; Biofuels; Dissolved inorganic carbon; Microalgae; Wastewater