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Case Study on Innovative Aquatic-Based Bioeconomy for Chlorella sorokiniana
Abstract:Over the last decade due to climate change and a strategy of natural resources preservation, the interest for the aquatic biomass has dramatically increased. Along with mitigation of the environmental pressure and connection of waste streams (including CO2 and heat emissions), microalgae bioeconomy can supply food, feed, as well as the pharmaceutical and power industry with number of value-added products. Furthermore, in comparison to conventional biomass, microalgae can be cultivated in wide range of conditions without compromising food and feed production, thus addressing issues associated with negative social and the environmental impacts. This paper presents the state-of-the art technology for microalgae bioeconomy from cultivation process to production of valuable components and by-streams. Microalgae Chlorella sorokiniana were cultivated in the pilot-scale innovation concept in Hamburg (Germany) using different systems such as race way pond (5000 L) and flat panel reactors (8 x 180 L). In order to achieve the optimum growth conditions along with suitable cellular composition for the further extraction of the value-added components, process parameters such as light intensity, temperature and pH are continuously being monitored. On the other hand, metabolic needs in nutrients were provided by addition of micro- and macro-nutrients into a medium to ensure autotrophic growth conditions of microalgae. The cultivation was further followed by downstream process and extraction of lipids, proteins and saccharides. Lipids extraction is conducted in repeated-batch semi-automatic mode using hot extraction method according to Randall. As solvents hexane and ethanol are used at different ratio of 9:1 and 1:9, respectively. Depending on cell disruption method along with solvents ratio, the total lipids content showed significant variations between 8.1% and 13.9 %. The highest percentage of extracted biomass was reached with a sample pretreated with microwave digestion using 90% of hexane and 10% of ethanol as solvents. Proteins content in microalgae was determined by two different methods, namely: Total Kejadahl Nitrogen (TKN), which further was converted to protein content, as well as Bradford method using Brilliant Blue G-250 dye. Obtained results, showed a good correlation between both methods with protein content being in the range of 39.8–47.1%. Characterization of neutral and acid saccharides from microalgae was conducted by phenol-sulfuric acid method at two wavelengths of 480 nm and 490 nm. The average concentration of neutral and acid saccharides under the optimal cultivation conditions was 19.5% and 26.1%, respectively. Subsequently, biomass residues are used as substrate for anaerobic digestion on the laboratory-scale. The methane concentration, which was measured on the daily bases, showed some variations for different samples after extraction steps but was in the range between 48% and 55%. CO2 which is formed during the fermentation process and after the combustion in the Combined Heat and Power unit can potentially be used within the cultivation process as a carbon source for the photoautotrophic synthesis of biomass.
Digital Object Identifier (DOI): doi.org/10.5281/zenodo.1340466Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 320
 Wijesekara I., Pangestuti R., Kim S.K., Biological activities and potential health benefits of sulfated polysaccharides derived from marine algae. Carbohydrate Polymers, 2011, 84, pp. 14-21.
 Schaeffer D. J., Krylov V. S., Anti-HIV activity of extracts and compounds from algae and cyanobacteria. Ecotoxicol Environ Saf, 2000, 45(3), pp. 208-227.
 Jiménez-Escrig A., Gómez-Ordóñez E., Rupérez P., Seaweed as a source of novel nutraceuticals: sulfated polysaccharides and peptides. Adv Food Nutr Res, 2011, 64, pp. 325-337.
 Swamy M., Marine algal sources for treating bacterial diseases. Advances in Food and Nutrition Research, 2011, 64, pp. 71-84.
 Zubia M., Fabre M. S., Kerjean V., Lann K. L., Stiger-Pouvreau V., Fauchon, M. et al., Antioxidant and antitumoural activities of some Phaeophyta from Brittany coasts. Food Chem, 2011, 116, pp. 693-701.
 Stout E. P, Prudhomme J., Roch K. L., Fairchild C. R., Franzblau S. G., Aalbersberg W., et al., Unusual antimalarial meroditerpenes from tropical red macroalgae. Bioorganic & Medicinal Chemistry Letters, 2020, 20, pp. 5662-5665.
 Kannan R. R. R., Arumugam R., Anantharaman P., Antibacterial potential of three seagrasses against human pathogens. Asian Pacific Journal of Tropical Medicine, 2010, 3, pp. 890-893.
 Zhang C., Li X, Kim S. K., Application of marine biomaterials for nutraceuticals and functional foods. Food Sci Biotechnol, 2012, 21, pp. 625-631.
 Alassali A., Cybulska I., Brudecki G. P., Brudecki G. P., Farzanah R., Thomsen M. H., Methods for Upstream Extraction and Chemical Characterization of Secondary Metabolites from Algae Biomass. Adv Tech Biol Med, 2016, 4, pp. 1-16.
 Hong-Wei Yen, I.-Chen Hu, Chun-Yen Chen, Shih-Hsin Ho, Duu-Jong Lee, Jo-Shu Chang, Microalgae-based biorefinery – From biofuels to natural products. Bioresource Technology, 2013, 135,pp. 166-174.
 Priyadarshani I., Rath B., Commercial and industrial application of micro algae – A review. J. Algal Biomass Utln., 2012, 3 (4), pp. 89 – 100.
 El-Sayed Salama, Kurade, M. B., Abou-Shanab, R. A. I., El-Dalatony, M. M., Il-Seung Yang, Min, B., et al., Recent progress in microalgal biomass production coupled with wastewater treatment for biofuel generation. Renewable and Sustainable Energy Reviews, 2017, 79, pp. 1189-1211.
 Wang B., Li Y., Wu N., Lan C.Q., CO2 bio-mitigation using microalgae. Appl Microbiol Biotechnol, 2008, 79 (5), pp. 707-718.
 Morita M., Watanabe Y., Saiki H., Photosynthetic productivity of conical helical tubular photobioreactor incorporating Chlorella sorokiniana under field conditions. In: Biotechnol. Bioeng., 2002, 77 (2), pp. 155-162.
 (dataset) SAG, 2014. Culture Collection of Algae at Göttingen University, List of Media and Recipes. http://www.uni-goettingen.de/de/list-of-media-and-recipes/186449.html.
 Lopez, C. V. G., Garcia, M. C. C., Fernandez, F. G. A., Buston, C. S., Christi, Y., Sevilla, J. M. F., Protein measurements of microalgal and cyanobacterial biomass. Bioresource Technology, 2010, 101, pp. 7587-7591.
 Bradford, M., A Rapid and Sensitive Method for the Quantitation of Microgram Quantities of Protein Utilizing the Principle of Protein-Dye Binding. Analytical Biochemistry,1976, 72, pp. 248-254.
 Dubois, M., Gilles, K., Hamilton, J. K, Rebers, P. A., Smith, F., Colorimetric Method for Determination of Sugars and Related Substances. Analytical Chemistry, 1956, 28 (3), pp. 350–356.
 Fermentation of organic materials. Characterization of the substrate, sampling, collection of material data, fermentation tests. Vergärung organischer Stoffe Substratcharakterisierung, Probenahme, Stoffdatenerhebung, Gärversuche, VDI 4630, 2016.