title: Lipid recovery from a vegetable oil emulsion using microbial enrichment cultures.
abstract: BACKGROUND
  Many waste streams have a relatively high vegetable oil content, which is a potential resource that should be recovered. Microbial storage compound production for the recovery of lipids from lipid-water emulsions with open (unsterilized) microbial cultures was investigated in a sequencing batch reactor using a diluted vegetable oil emulsion as model substrate.
  
  
  RESULTS
  After feeding, triacylglycerides (TAG) were accumulated intracellular by the microbial enrichment culture and subsequently used for growth in the remainder of the sequencing batch cycle. Roughly 50% of the added TAG could be recovered as intracellular lipids in this culture. The maximum lipid storage capacity of the enrichment culture was 54% on volatile suspended solids (VSS) mass basis in a separate fed-batch accumulation experiment. The microbial community was dominated by a lipolytic fungus, Trichosporon gracile, that was responsible for intracellular lipid accumulation but also a significant fraction of lipolytic and long chain fatty-acid-utilizing bacteria was present.
  
  
  CONCLUSIONS
  Herewith, we demonstrate an effective strategy for enrichment of a microbial community that can accumulate significant amounts of lipids from wastewaters without the need for sterilization of substrates or equipment. Further optimization of this process will make recovery of lipids from wastewater possible.
authors: Department of Biotechnology, Delft University of Technology, Julianalaan 67, 2628 BC Delft, The Netherlands.
authors: Jelmer
authors: J
authors: Tamis
authors: Department of Biotechnology, Delft University of Technology, Julianalaan 67, 2628 BC Delft, The Netherlands ; Winogradsky Institute of Microbiology, RAS, Leninskii avenue, 14, Leninskii avenue, 32а, Moscow, 119991 Russia.
authors: Dimitry Y
authors: DY
authors: Sorokin
authors: Department of Biotechnology, Delft University of Technology, Julianalaan 67, 2628 BC Delft, The Netherlands.
authors: Yang
authors: Y
authors: Jiang
authors: Department of Biotechnology, Delft University of Technology, Julianalaan 67, 2628 BC Delft, The Netherlands.
authors: Mark C M
authors: MC
authors: van Loosdrecht
authors: Department of Biotechnology, Delft University of Technology, Julianalaan 67, 2628 BC Delft, The Netherlands.
authors: Robbert
authors: R
authors: Kleerebezem
keywords: Feast-famine; Microbial enrichment culture; Resource recovery; Storage compounds; Vegetable oil