title: Enhancement of lutein production in Chlorella sorokiniana (Chorophyta) by improvement of culture conditions and random mutagenesis.
abstract: Chlorella sorokiniana has been selected for lutein production, after a screening of thirteen species of microalgae, since it showed both a high content in this carotenoid and a high growth rate. The effects of several nutritional and environmental factors on cell growth and lutein accumulation have been studied. Maximal specific growth rate and lutein content were attained at 690 μmol photons m(-2) s(-1), 28 °C, 2 mM NaCl, 40 mM nitrate and under mixotrophic conditions. In general, optimal conditions for the growth of this strain also lead to maximal lutein productivity. High lutein yielding mutants of C. sorokiniana have been obtained by random mutagenesis, using N-methyl-N'-nitro-nitrosoguanidine (MNNG) as a mutagen and selecting mutants by their resistance to the inhibitors of the carotenogenic pathway nicotine and norflurazon. Among the mutants resistant to the herbicides, those exhibiting both high content in lutein and high growth rate were chosen. Several mutants exhibited higher contents in this carotenoid than the wild type, showing, in addition, either a similar or higher growth rate than the latter strain. The mutant MR-16 exhibited a 2.0-fold higher volumetric lutein content than that of the wild type, attaining values of 42.0 mg L(-1) and mutants DMR-5 and DMR-8 attained a lutein cellular content of 7.0 mg g(-1) dry weight. The high lutein yield exhibited by C. sorokiniana makes this microalga an excellent candidate for the production of this commercially interesting pigment.
authors: Institute of Plant Biochemistry and Photosynthesis, CIC Cartuja, University of Seville and CSIC, Avda. Americo Vespucio no. 49, 41092-Seville, Spain.
authors: Baldo F
authors: BF
authors: Cordero
authors: Institute of Plant Biochemistry and Photosynthesis, CIC Cartuja, University of Seville and CSIC, Avda. Americo Vespucio no. 49, 41092-Seville, Spain.
authors: Irina
authors: I
authors: Obraztsova
authors: Institute of Plant Biochemistry and Photosynthesis, CIC Cartuja, University of Seville and CSIC, Avda. Americo Vespucio no. 49, 41092-Seville, Spain.
authors: Inmaculada
authors: 0000-0003-2849-675X
authors: I
authors: Couso
authors: Department of Chemistry, Experimental Sciences Faculty, University of Huelva, Avda. Fuerzas Armadas s/n, 21071-Huelva, Spain.
authors: Rosa
authors: R
authors: Leon
authors: Institute of Plant Biochemistry and Photosynthesis, CIC Cartuja, University of Seville and CSIC, Avda. Americo Vespucio no. 49, 41092-Seville, Spain.
authors: Maria Angeles
authors: MA
authors: Vargas
authors: Institute of Plant Biochemistry and Photosynthesis, CIC Cartuja, University of Seville and CSIC, Avda. Americo Vespucio no. 49, 41092-Seville, Spain.
authors: Herminia
authors: H
authors: Rodriguez
mesh_terms: D002708:Chlorella / Q000254:growth & development / Q000378:metabolism*; D003470:Culture Media; D005947:Glucose / Q000494:pharmacology; D014975:Lutein / Q000096:biosynthesis*; D016296:Mutagenesis; D009584:Nitrogen / Q000494:pharmacology; D013696:Temperature
chemical_list: D003470:Culture Media; D005947:Glucose; D009584:Nitrogen; D014975:Lutein