title: Enhancing the value of nitrogen from rapeseed meal for microbial oil production.
abstract: Rapeseed meal, a major byproduct of biodiesel production, has been used as a low-cost raw material for the production of a generic microbial feedstock through a consolidated bioconversion process. Various strategies were tested for the production of a novel fermentation medium, rich in free amino nitrogen (FAN): commercial enzymes (CEs) (2.7 mg g⁻¹ dry meal), liquid state fungal pre-treatment (LSF) using Aspergillus oryzae (4.6 mg g⁻¹), liquid state fungal pre-treatment followed by fungal autolysis (LSFA) (9.13 mg g⁻¹), liquid state pre-treatment using fungal enzymatic broth (EB) (2.1 mg g⁻¹), but the best strategy was a solid state fungal pre-treatment followed by fungal autolysis (34.5 mg g⁻¹). The bioavailability of the nitrogen sources in the novel medium was confirmed in fed-batch bioreactor studies, in which 82.3g dry cell L⁻¹ of the oleaginous yeast Rhodosporidium toruloides Y4 was obtained with a lipid content of 48%. The dry cell weight obtained was higher than that obtained using conventional yeast extract, due to a higher total nitrogen content in the novel biomedium. The fatty acids obtained from the microbial oil were similar to those derived from rapeseed oil.
authors.affiliation: School of Chemical Engineering and Analytical Science, Manchester University, Oxford Road, Manchester M13 9PL, United Kingdom.
authors.forename: Esra
authors.initials: E
authors.lastname: Uçkun Kiran
authors.forename: Apilak
authors.initials: A
authors.lastname: Salakkam
authors.forename: Antoine P
authors.initials: AP
authors.lastname: Trzcinski
authors.forename: Ufuk
authors.initials: U
authors.lastname: Bakir
authors.forename: Colin
authors.initials: C
authors.lastname: Webb
mesh_terms: D001487:Basidiomycota / Q000235:genetics / Q000254:growth & development / Q000378:metabolism*; D056804:Biofuels; D019149:Bioreactors; D001709:Biotechnology / Q000379:methods*; D029741:Brassica rapa / Q000378:metabolism* / Q000382:microbiology; D003470:Culture Media; D005285:Fermentation; D008055:Lipids / Q000096:biosynthesis; D009584:Nitrogen / Q000378:metabolism*; D009821:Oils / Q000378:metabolism*
chemical_list: D056804:Biofuels; D003470:Culture Media; D008055:Lipids; D009821:Oils; D009584:Nitrogen