Outdoor culture of Halamphora coffeaeformis in the semi-arid Pampa of Argentina: A comprehensive analysis of triacylglycerol production for biodiesel

The feasibility of microalgal triacylglycerol (TAG) production for biodiesel remains constrained by high production costs under outdoor conditions. The aim of this study was to evaluate the capacity of an Argentinian strain of the diatom Halamphora coffeaeformis grown in outdoor raceway ponds to pro...

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Detalles Bibliográficos
Autores: Navarro, Francisco Ezequiel, Leonardi, Patricia Ines, Damiani, Maria Cecilia, Martin, Lucas Ariel, Martínez, A. M., Popovich, Cecilia Angelines
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2023
País:Argentina
Institución:Consejo Nacional de Investigaciones Científicas y Técnicas
Repositorio:CONICET Digital (CONICET)
Idioma:inglés
OAI Identifier:oai:ri.conicet.gov.ar:11336/216063
Acceso en línea:http://hdl.handle.net/11336/216063
Access Level:acceso embargado
Palabra clave:BIODIESEL
BIOENERGY CULTURE
DIATOMS
RACEWAY POND
SEAWATER
https://purl.org/becyt/ford/1.6
https://purl.org/becyt/ford/1
Descripción
Sumario:The feasibility of microalgal triacylglycerol (TAG) production for biodiesel remains constrained by high production costs under outdoor conditions. The aim of this study was to evaluate the capacity of an Argentinian strain of the diatom Halamphora coffeaeformis grown in outdoor raceway ponds to produce TAG suitable for biodiesel. The strain was cultured in seawater enriched with a biofertilizer during summer and spring in the semi-arid Pampa of Argentina. The following variables were analysed: 1) growth rate; 2) TAG accumulation; 3) lipid content and quality; 4) dissolved nutrient and physicochemical properties; and 5) climatic conditions. Intracellular TAG accumulation was evaluated with fluorometry by Nile Red. The growth rate and biomass productivity of the species were similar in the two seasons, with approximate values of 1.35 div. day−1 and 61.25 kg.ha−1.day−1, respectively. Total lipid content increased about 4-fold with respect to inocula in the 2 cultures, reaching up to 44.7 % ash free dry weight (AFDW) in summer and 36.4 % AFDW in spring. However, lipid accumulation differed between seasons: neutral lipid accumulation began at 8 days of cultivation in summer and at 19 days in spring. Salinity was the main stressor that accelerated the TAG accumulation in the species, the nutrient levels did not reach limiting values. In spring, precipitation decreased salinity levels, reducing stress and delaying the onset of TAG accumulation. The biodiesel properties inferred from the fatty acid profile of the species meet international standards and their quality ensures good performance in cold climates. Furthermore, the reported lipid productivity of the species (~25.6 kg.ha−1.day−1) is higher than that of the soybean oil used commercially for biodiesel. Based on the results obtained, H. coffeaeformis has potential for exploitation as a renewable source of TAG for biodiesel production in arid and semi-arid environments with access to brackish or marine water.