title: Elucidating the Effect of Glycerol Concentration and C/N Ratio on Lipid Production Using Yarrowia lipolytica SKY7.
abstract: The high demand for renewable energy and increased biodiesel production lead to the surplus availability of crude glycerol. Due to the above reason, the bio-based value addition of crude glycerol into various bioproducts is investigated; among them, microbial lipids are attractive. The present study was dedicated to find the optimal glycerol concentration and carbon/nitrogen (C/N) ratio to produce maximum lipid using Yarrowia lipolytica SKY7. The glycerol concentration (34.4 to168.2 g/L) and C/N ratio (25 to 150) were selected to investigate to maximize the lipid production. Initial glycerol concentration 112.5 g/L, C/N molar ratio of 100, and with 5 % v/v inoculum supplementation were found to be optimum for biomass and lipid production. Based on the above optimal parameters, lipid concentration of 43.8 % w/w with a biomass concentration of 14.8 g/L was achieved. In the case of glycerol concentration, the maximum Yp/s (0.192 g/g); Yx/s (0.43 g/g) was noted when the initial glycerol concentration was 112.5 g/L with C/N molar ratio 100 and inoculum volume 5 % v/v. The glycerol uptake was also noted to increase with the increase in glycerol concentration. At low C/N ratio, the glycerol consumption was found to be high (79.43 g/L on C/N 25) whereas the glycerol consumption was observed to decrease when the C/N ratio was raised to 150 (40.8 g/L).
authors.affiliation: Institut National de la Recherche Scientifique, Centre Eau, Terre & Environnement, Université du Québec, 490 de la Couronne, QC, G1K 9A9, Canada.
authors.forename: Mathiazhakan
authors.initials: M
authors.lastname: Kuttiraja
authors.affiliation: Institut National de la Recherche Scientifique, Centre Eau, Terre & Environnement, Université du Québec, 490 de la Couronne, QC, G1K 9A9, Canada.
authors.forename: Ayed
authors.initials: A
authors.lastname: Douha
authors.affiliation: Institut National de la Recherche Scientifique, Centre Eau, Terre & Environnement, Université du Québec, 490 de la Couronne, QC, G1K 9A9, Canada.
authors.forename: Jose R
authors.initials: JR
authors.lastname: Valéro
authors.affiliation: Institut National de la Recherche Scientifique, Centre Eau, Terre & Environnement, Université du Québec, 490 de la Couronne, QC, G1K 9A9, Canada. rd.tyagi@ete.inrs.ca.
authors.forename: Rajeswar Dayal
authors.initials: RD
authors.lastname: Tyagi
mesh_terms: D018533:Biomass; D002244:Carbon / Q000032:analysis*; D005990:Glycerol / Q000494:pharmacology*; D008055:Lipids / Q000096:biosynthesis; D009584:Nitrogen / Q000032:analysis*; D014131:Trace Elements / Q000494:pharmacology; D014280:Triglycerides / Q000378:metabolism; D025062:Yarrowia / Q000187:drug effects / Q000254:growth & development / Q000378:metabolism*
chemical_list: D008055:Lipids; D014131:Trace Elements; D014280:Triglycerides; D002244:Carbon; D009584:Nitrogen; D005990:Glycerol
keywords: Biodiesel; C/N ratio; Crude glycerol; Microbial lipid; Y. lipolytica