This paper focuses on an autotrophic cultivation of Chlorella vulgaris, in low nitrogen-content media, using indoor photobioreactors. Nutritional factors, which controlled the Chlorella growth and the chemical composition of cells (., proteins, carbohydrates, lipids), were studied. The moderate feeding of both N and P and/or their starvation in the photobioreactor were investigated in order to induce a high accumulation of lipids into Chorella cells. | Energies 2014, 7, 3840-3857; doi: OPEN ACCESS energies ISSN 1996-1073 Article Batch Growth of Chlorella Vulgaris CCALA 896 versus Semi-Continuous Regimen for Enhancing Oil-Rich Biomass Productivity Sigita Vaičiulytė 1,2, Giulia Padovani 3, Jolanta Kostkevičienė 1 and Pietro Carlozzi 3,* 1 2 3 Department of Botany and Genetics, Faculty of Natural Sciences, Vilnius University, 21/27, Vilnius LT-03101, Lithuania; E-Mails: sigittta@ (.); (.) Department of Chemical and Biological Engineering, Division of Industrial Biotechnology, Chalmers University of Technology, Kemivä 10, Gothenburg SE-412 96, Sweden gen Institute of Ecosystem Study, National Research Council (CNR), Section of Florence, Polo Scientifico, Via Madonna del Piano n. 10, Sesto Fiorentino (FI) IT-50019, Italy; E-Mail: * Author to whom correspondence should be addressed; E-Mail: ; Tel.: +39-055-5225-962; Fax: +39-055-5225-920. Received: 10 March 2014; in revised form: 7 May 2014 / Accepted: 11 June 2014 / Published: 19 June 2014 Abstract: The aim of this study was to induce lipid accumulation in Chlorella cells by creating stressful growth conditions. Chlorella vulgaris CCALA 896 was grown under various batch growth modes in basal and modified BG-11 and Kolkwitz culture broths, using a continuous light regimen of 150 µ 2/s, at 30 ° In order to perform the E/m C. experiments, two indoor photobioreactor shapes were used: a cylindrical glass photobioreactor (CGPBR) with a working volume of 350 mL, and a flat glass photobioreactor (FGPBR) with a working volume of 550 mL. Stress-eliciting conditions, such as nitrogen and phosphorous starvation, were imposed in order to induce lipid accumulation. The results demonstrated that more than 56% of the lipids can be accumulated in Chlorella biomass grown under two-phase batch growth conditions. The highest .
