title: Effects of nutritional conditions on growth and biochemical composition of Tetraselmis sp.
abstract: BACKGROUND
  This study aimed to maximize biomass concentration, biomass productivity and biochemical composition of the marine microalga Tetraselmis sp.
  
  
  METHODS
  In the current study, Box-Behnken Design was used to model the effect of NaNO3, NaH2PO4, metals and vitamins in the F/2 medium on the growth, total chlorophylls, carotenoids and starch contents. The total chlorophylls content was quantified by spectrophotometry. The FT-IR spectroscopy was used to estimate the biochemical compositions of Tetraselmis sp. grown under both optimized medium culture for starch production and standard culture medium.
  
  
  RESULTS
  Finalized NaNO3(1.76 mM), NaH2PO4(0.018 mM), metals (1500 μL.L-1) and vitamins (312.5 μL.L-1) concentrations, generated an increase in biomass concentration up to 5.72 g.L-1which contributed to an increase about 2.4-fold than that of the standard conditions of biomass productivity (408.57 mg.L-1.day-1). The maximum value of carotenoids content (0.3 mg.g DW-1) was achieved at the highest level of all factors. The total chlorophylls content reached also its maximum (5.18 mg.g DW-1) at high nitrate (1.76 mM), phosphate (0.054 mM), metals and vitamins concentrations, while the maximum starch content (42% DW) was achieved with low nitrate and phosphate concentrations (0.58 mM and 0.027 mM) and with metals and vitamins limitations. Thus, the nitrogen, phosphorus, metals and vitamins limitations led to divert the metabolism for the starch biosynthesis.
  
  
  CONCLUSIONS
  The high biomass concentration productivity and starch production make Tetraselmis sp. strain a good candidate for biotechnological applications.
authors.affiliation: Unité de Biotechnologie des Algues, Biological Engineering Department, National School of Engineers of Sfax, University of Sfax, Sfax, Tunisia.
authors.forename: Mouna
authors.initials: M
authors.lastname: Dammak
authors.affiliation: Unité de Biotechnologie des Algues, Biological Engineering Department, National School of Engineers of Sfax, University of Sfax, Sfax, Tunisia.
authors.forename: Bilel
authors.initials: B
authors.lastname: Hadrich
authors.affiliation: Unité de Biotechnologie des Algues, Biological Engineering Department, National School of Engineers of Sfax, University of Sfax, Sfax, Tunisia.
authors.forename: Ramzi
authors.initials: R
authors.lastname: Miladi
authors.affiliation: Unité de Biotechnologie des Algues, Biological Engineering Department, National School of Engineers of Sfax, University of Sfax, Sfax, Tunisia.
authors.forename: Mohamed
authors.initials: M
authors.lastname: Barkallah
authors.affiliation: Unité de Biotechnologie des Algues, Biological Engineering Department, National School of Engineers of Sfax, University of Sfax, Sfax, Tunisia.
authors.forename: Faiez
authors.initials: F
authors.lastname: Hentati
authors.affiliation: Unité de Biotechnologie des Algues, Biological Engineering Department, National School of Engineers of Sfax, University of Sfax, Sfax, Tunisia.
authors.forename: Ridha
authors.initials: R
authors.lastname: Hachicha
authors.affiliation: Université Clermont Auvergne, Université Blaise Pascal, Institut Pascal, BP 10448, F-63000, Clermont-Ferrand, France.|CNRS, UMR 6602, IP, F-63178, Aubière, France.
authors.forename: Céline
authors.initials: C
authors.lastname: Laroche
authors.affiliation: Université Clermont Auvergne, Université Blaise Pascal, Institut Pascal, BP 10448, F-63000, Clermont-Ferrand, France.|CNRS, UMR 6602, IP, F-63178, Aubière, France.
authors.forename: Philippe
authors.initials: P
authors.lastname: Michaud
authors.affiliation: Laboratory of Plant Biotechnology, Faculty of Sciences of Sfax, University of Sfax, Sfax, Tunisia.
authors.forename: Imen
authors.initials: I
authors.lastname: Fendri
authors.affiliation: Unité de Biotechnologie des Algues, Biological Engineering Department, National School of Engineers of Sfax, University of Sfax, Sfax, Tunisia. slim.abdelkafi@enis.tn.
authors.forename: Slim
authors.initials: S
authors.lastname: Abdelkafi
mesh_terms: D002338:Carotenoids / Q000378:metabolism; D018929:Cell Culture Techniques; D002478:Cells, Cultured; D002734:Chlorophyll / Q000378:metabolism; D000460:Chlorophyta / Q000254:growth & development* / Q000378:metabolism; D003470:Culture Media; D058086:Microalgae / Q000254:growth & development* / Q000378:metabolism; D013213:Starch / Q000378:metabolism
chemical_list: D003470:Culture Media; D002734:Chlorophyll; D002338:Carotenoids; D013213:Starch
keywords: Bioactive compounds; Biomass; Box-Behnken Design; Microalgae; Starch; Tetraselmis sp.