title: Effect of selenate on viability and selenomethionine accumulation of Chlorella sorokiniana grown in batch culture.
abstract: The aim of this work was to study the effect of Se(+VI) on viability, cell morphology, and selenomethionine accumulation of the green alga Chlorella sorokiniana grown in batch cultures. Culture exposed to sublethal Se concentrations of 40 mg · L(-1) (212 μM) decreased growth rates for about 25% compared to control. A selenate EC50 value of 45 mg · L(-1) (238.2 μM) was determined. Results showed that chlorophyll and carotenoids contents were not affected by Se exposure, while oxygen evolution decreased by half. Ultrastructural studies revealed granular stroma, fingerprint-like appearance of thylakoids which did not compromise cell activity. Unlike control cultures, SDS PAGE electrophoresis of crude extracts from selenate-exposed cell cultures revealed appearance of a protein band identified as 53 kDa Rubisco large subunit of Chlorella sorokiniana, suggesting that selenate affects expression of the corresponding chloroplast gene as this subunit is encoded in the chloroplast DNA. Results revealed that the microalga was able to accumulate up to 140 mg · kg(-1) of SeMet in 120 h of cultivation. This paper shows that Chlorella sorokiniana biomass can be enriched in the high value aminoacid SeMet in batch cultures, while keeping photochemical viability and carbon dioxide fixation activity intact, if exposed to suitable sublethal concentrations of Se.
authors.affiliation: Algal Biotechnology Group, Department of Chemistry and Material Sciences, Faculty of Experimental Sciences, University of Huelva, Campus el Carmen, Avenida de las Fuerzas Armadas s/n, 21007 Huelva, Spain ; Department of Food Technology and Biotechnology, Faculty of Chemistry, Brno University of Technology, Purkyňova 118, 61200 Brno, Czech Republic.
authors.forename: Živan
authors.identifier: 0000-0002-7916-5427
authors.initials: Ž
authors.lastname: Gojkovic
authors.affiliation: Algal Biotechnology Group, Department of Chemistry and Material Sciences, Faculty of Experimental Sciences, University of Huelva, Campus el Carmen, Avenida de las Fuerzas Armadas s/n, 21007 Huelva, Spain ; Algal Biotechnology Group, International Centre for Environmental Research (CIECEM), Parque Dunar s/n, Matalascaňas, Almonte, 21760 Huelva, Spain.
authors.forename: Carlos
authors.initials: C
authors.lastname: Vílchez
authors.affiliation: Department of Environmental Biology and Public Health, University of Huelva, Campus el Carmen, 21007 Huelva, Spain.
authors.forename: Rafael
authors.initials: R
authors.lastname: Torronteras
authors.affiliation: Algal Biotechnology Group, Department of Chemistry and Material Sciences, Faculty of Experimental Sciences, University of Huelva, Campus el Carmen, Avenida de las Fuerzas Armadas s/n, 21007 Huelva, Spain.
authors.forename: Javier
authors.initials: J
authors.lastname: Vigara
authors.affiliation: Department of Chemistry and Material Sciences, University of Huelva, Campus el Carmen, 21007 Huelva, Spain.
authors.forename: Veronica
authors.initials: V
authors.lastname: Gómez-Jacinto
authors.affiliation: University of Applied Science, Giessen, Wiesenstrasse 14, 35390 Giessen, Germany.
authors.forename: Nora
authors.initials: N
authors.lastname: Janzer
authors.affiliation: Department of Chemistry and Material Sciences, University of Huelva, Campus el Carmen, 21007 Huelva, Spain.
authors.forename: José-Luis
authors.initials: JL
authors.lastname: Gómez-Ariza
authors.affiliation: Department of Food Technology and Biotechnology, Faculty of Chemistry, Brno University of Technology, Purkyňova 118, 61200 Brno, Czech Republic.
authors.forename: Ivana
authors.initials: I
authors.lastname: Márová
authors.affiliation: Algal Biotechnology Group, Department of Chemistry and Material Sciences, Faculty of Experimental Sciences, University of Huelva, Campus el Carmen, Avenida de las Fuerzas Armadas s/n, 21007 Huelva, Spain.
authors.forename: Ines
authors.identifier: 0000-0002-0656-4523
authors.initials: I
authors.lastname: Garbayo
mesh_terms: D061249:Batch Cell Culture Techniques / Q000379:methods*; D019149:Bioreactors / Q000382:microbiology*; D049109:Cell Proliferation / Q000187:drug effects / Q000502:physiology; D048429:Cell Size / Q000187:drug effects; D002470:Cell Survival / Q000187:drug effects / Q000502:physiology; D002708:Chlorella / Q000166:cytology* / Q000187:drug effects / Q000502:physiology*; D004305:Dose-Response Relationship, Drug; D064586:Selenic Acid / Q000008:administration & dosage*; D012645:Selenomethionine / Q000302:isolation & purification* / Q000378:metabolism*
chemical_list: D012645:Selenomethionine; D064586:Selenic Acid