title: New dual-stage pH control fed-batch cultivation strategy for the improvement of lipids and carotenoids production by the red yeast Rhodosporidium toruloides NCYC 921.
abstract: The optimal medium pH to produce biomass and fatty acids by the red yeast Rhodosporidium toruloides NCYC 921 is 4.0, and to produce carotenoids is 5.0. Based on this difference, a dual-stage pH control fed-batch cultivation strategy for the enhancement of lipids and carotenoids production by this yeast was studied. The results showed that when the yeast growth phase was conducted at pH 4.0, and the products accumulation phase was conducted at pH 5.0, biomass, total fatty acid and total carotenoid productivities were significantly improved comparing with the yeast fed batch cultivations carried out at fixed medium pH (4 or 5). Under dual-stage pH control conditions, the biomass, carotenoids and lipids productivities attained 2.35 g/Lh, 0.29 g/Lh and 0.40 g/Lh, respectively. It was also observed that the oxygen played a major role in the yeast carotenoid production.
authors.affiliation: Laboratório Nacional de Energia e Geologia-LNEG, I.P., Unidade de Bioenergia, BBRI-Infraestrutura de Investigação em Biomassa e Bioenergia, Estrada do Paço do Lumiar, 22, 1649-038 Lisboa, Portugal.
authors.forename: Carla
authors.initials: C
authors.lastname: Dias
authors.affiliation: Laboratório Nacional de Energia e Geologia-LNEG, I.P., Unidade de Bioenergia, BBRI-Infraestrutura de Investigação em Biomassa e Bioenergia, Estrada do Paço do Lumiar, 22, 1649-038 Lisboa, Portugal.
authors.forename: Sofia
authors.initials: S
authors.lastname: Sousa
authors.affiliation: Laboratório Nacional de Energia e Geologia-LNEG, I.P., Unidade de Bioenergia, BBRI-Infraestrutura de Investigação em Biomassa e Bioenergia, Estrada do Paço do Lumiar, 22, 1649-038 Lisboa, Portugal.
authors.forename: João
authors.initials: J
authors.lastname: Caldeira
authors.affiliation: Laboratório Nacional de Energia e Geologia-LNEG, I.P., Unidade de Bioenergia, BBRI-Infraestrutura de Investigação em Biomassa e Bioenergia, Estrada do Paço do Lumiar, 22, 1649-038 Lisboa, Portugal.
authors.forename: Alberto
authors.initials: A
authors.lastname: Reis
authors.affiliation: Laboratório Nacional de Energia e Geologia-LNEG, I.P., Unidade de Bioenergia, BBRI-Infraestrutura de Investigação em Biomassa e Bioenergia, Estrada do Paço do Lumiar, 22, 1649-038 Lisboa, Portugal. Electronic address: teresa.lopessilva@lneg.pt.
authors.forename: Teresa
authors.initials: T
authors.lastname: Lopes da Silva
mesh_terms: D001487:Basidiomycota / Q000254:growth & development* / Q000378:metabolism*; D061249:Batch Cell Culture Techniques / Q000379:methods*; D056804:Biofuels / Q000382:microbiology; D018533:Biomass; D002338:Carotenoids / Q000096:biosynthesis*; D005227:Fatty Acids / Q000096:biosynthesis; D006863:Hydrogen-Ion Concentration; D008055:Lipids / Q000096:biosynthesis*
chemical_list: D056804:Biofuels; D005227:Fatty Acids; D008055:Lipids; D002338:Carotenoids
keywords: Biomass; Carotenoids; Fatty acids; Rhodosporidium toruloides; pH