title: Production of docosahexaenoic acid by Crypthecodinium cohnii grown in a pH-auxostat culture with acetic acid as principal carbon source.
abstract: Crypthecodinium cohnii, a marine alga used for the commercial production of docosahexaenoic acid (DHA), was cultivated in medium containing sodium acetate as principal carbon source; the pH was maintained at a constant value by addition of acetic acid, which also provided an additional carbon source in a controlled manner. The accumulation of lipid by C. cohnii in this pH-auxostat culture was significantly greater than previously reported for batch cultures using glucose as principal carbon source. Of six strains tested in pH-auxostat cultures, C. cohnii ATCC 30772 was the best, with the cells reaching 20 to 30 g dry weight per liter after 98 to 144 h and containing in excess of 40% (w/w) total lipid, with DHA representing approximately half of the total fatty acids in the triacylglycerol fraction. A productivity of 36 mg DHA L(-1) h(-1) was achieved during cultivation for 98 h using a 5% (vol/vol) inoculum, and DHA production was in excess of 3 g per liter of culture. Most of the DHA was present in neutral lipids.
authors.affiliation: Lipid Research Centre, Department of Biological Sciences, University of Hull, United Kingdom. C.Ratledge@hull.ac.uk
authors.forename: C
authors.initials: C
authors.lastname: Ratledge
authors.forename: K
authors.initials: K
authors.lastname: Kanagachandran
authors.forename: A J
authors.initials: AJ
authors.lastname: Anderson
authors.forename: D J
authors.initials: DJ
authors.lastname: Grantham
authors.forename: J C
authors.initials: JC
authors.lastname: Stephenson
mesh_terms: D019342:Acetic Acid / Q000378:metabolism; D001709:Biotechnology / Q000379:methods*; D002244:Carbon / Q000378:metabolism; D002455:Cell Division; D005591:Chemical Fractionation; D004281:Docosahexaenoic Acids / Q000378:metabolism*; D056890:Eukaryota / Q000254:growth & development / Q000378:metabolism*; D006863:Hydrogen-Ion Concentration; D008055:Lipids / Q000737:chemistry
chemical_list: D008055:Lipids; D004281:Docosahexaenoic Acids; D002244:Carbon; D019342:Acetic Acid