title: Direct measurement and characterization of active photosynthesis zones inside wastewater remediating and biofuel producing microalgal biofilms.
abstract: Microalgal biofilm based technologies are of keen interest due to their high biomass concentrations and ability to utilize light and CO2. While photoautotrophic biofilms have long been used for wastewater remediation, biofuel production represents a relatively new and under-represented focus area. However, the direct measurement and characterization of fundamental parameters required for industrial control are challenging due to biofilm heterogeneity. This study evaluated oxygenic photosynthesis and respiration on two distinct microalgal biofilms cultured using a novel rotating algal biofilm reactor operated at field- and laboratory-scales. Clear differences in oxygenic photosynthesis and respiration were observed based on different culturing conditions, microalgal composition, light intensity and nitrogen availability. The cultures were also evaluated as potential biofuel synthesis strategies. Nitrogen depletion was not found to have the same effect on lipid accumulation compared to traditional planktonic microalgal studies. Physiological characterizations of these microalgal biofilms identify fundamental parameters needed to understand and control process optimization.
authors: Center for Biofilm Engineering, Montana State University, Bozeman, MT 59717, United States; Department of Chemical and Biological Engineering, Montana State University, Bozeman, MT 59717, United States; Chemical and Biological Signature Science, Pacific Northwest National Laboratories, Richland, WA 99352, United States.
authors: Hans C
authors: HC
authors: Bernstein
authors: Department of Biological Engineering, Utah State University, Logan, UT 84322, United States.
authors: Maureen
authors: M
authors: Kesaano
authors: Center for Biofilm Engineering, Montana State University, Bozeman, MT 59717, United States; Department of Microbiology, Montana State University, Bozeman, MT 59717, United States.
authors: Karen
authors: K
authors: Moll
authors: Department of Biological Engineering, Utah State University, Logan, UT 84322, United States.
authors: Terence
authors: T
authors: Smith
authors: Center for Biofilm Engineering, Montana State University, Bozeman, MT 59717, United States; Department of Chemical and Biological Engineering, Montana State University, Bozeman, MT 59717, United States.
authors: Robin
authors: R
authors: Gerlach
authors: Center for Biofilm Engineering, Montana State University, Bozeman, MT 59717, United States; Department of Chemical and Biological Engineering, Montana State University, Bozeman, MT 59717, United States.
authors: Ross P
authors: RP
authors: Carlson
authors: Department of Biological Engineering, Utah State University, Logan, UT 84322, United States.
authors: Charles D
authors: CD
authors: Miller
authors: Center for Biofilm Engineering, Montana State University, Bozeman, MT 59717, United States; Department of Chemical and Biological Engineering, Montana State University, Bozeman, MT 59717, United States.
authors: Brent M
authors: BM
authors: Peyton
authors: Environmental Biotechnology Consultants, Manhattan, MT 59741, United States.
authors: Keith E
authors: KE
authors: Cooksey
authors: Center for Biofilm Engineering, Montana State University, Bozeman, MT 59717, United States; Department of Chemical and Biological Engineering, Montana State University, Bozeman, MT 59717, United States. Electronic address: rob.gardner@biofilm.montana.edu.
authors: Robert D
authors: RD
authors: Gardner
authors: Department of Biological Engineering, Utah State University, Logan, UT 84322, United States. Electronic address: ron.sims@usu.edu.
authors: Ronald C
authors: RC
authors: Sims
mesh_terms: D000332:Aerobiosis; D001673:Biodegradation, Environmental; D018441:Biofilms / Q000254:growth & development; D056804:Biofuels / Q000382:microbiology*; D019149:Bioreactors / Q000382:microbiology; D004952:Esters / Q000378:metabolism; D058086:Microalgae / Q000502:physiology*; D009584:Nitrogen / Q000172:deficiency; D010100:Oxygen / Q000032:analysis; D010788:Photosynthesis; D062065:Wastewater / Q000382:microbiology*; D018508:Water Purification / Q000379:methods*
chemical_list: D056804:Biofuels; D004952:Esters; D009584:Nitrogen; D010100:Oxygen; D062065:Wastewater
keywords: Biofilm; Biofuel; Microalgae; Photosynthesis; Wastewater remediation