Extracellular carotenoid production and fatty acids profile of Parachlorella kessleri under increased CO2 concentrations

Autor(es)

Carvalho de Jesus, Priscila da Costa ^[1] ; Mendes, Maria Anita ^[1] ; Perpetuo, Elen Aquino ^{[2, 3]} ; Basso, Thiago Olitta ^[1] ; Oller do Nascimento, Claudio Augusto ^[1]

Afiliação do(s) autor(es)

^[1] Univ Sao Paulo, Dept Chem Engn, Escola Politecn, Sao Paulo - Brazil

^[2] Univ Sao Paulo, Ctr Estudos & Pesquisa Meio Ambiente CEPEMA, Cubatao - Brazil

^[3] Univ Fed Sao Paulo, Inst Marine Sci, UNIFESP, Santos, SP - Brazil

• Tipo de documento: Artigo Científico
• Fonte: Journal of Biotechnology; v. 329, p. 151-159, MAR 10 2021.
• Citações Web of Science: 3

Resumo

Large-scale cultivations of photoautotrophic microorganisms represent a very promising and potentially cost-effective alternative for climate change mitigation, when associated to the co-production of high value bioproducts, such as fatty acids and carotenoids, considering the growing demand for natural products. During microalgae cultivation, CO2 enrichment is a requirement to reach high productivities, although high CO2 levels are normally stressful to microalgae. On the other hand, cellular stress is a well reported strategy to induce carotenoid and fatty acids production. This work evaluated extracellular carotenoid production from the mangrove-isolated microalga Parachlorella kessleri cultivated under 5, 15 and 30% CO2 in stirred tank photo-bioreactors. In the 10th day of cultivation, CO2 supply was interrupted until the end of the cultivation (14th day), causing a stressful and imperative condition for microalgae cells to release the red pigment. Growth kinetics, physiological parameters and bioproducts production were evaluated. Growth kinetics were similar under all tested conditions and differences were not statistically significant, with the highest values of mu max, biomass concentration, lipid content and CO2 fixation rate of 0.77 d(-1), 1.24 g L-1, 241 mg g(-1) (dw) and 165 mg L-1 d(-1), respectively. In contrast, total carotenoid concentrations varied significantly (p < 0.01), with the highest concentration of 0.030 mu g mL(-1) under 5% CO2. The produced red pigment presented antioxidant activity and characteristics of carotenoids confirmed by UV-vis and tandem mass spectrometry (MS/MS). The fatty acid profiles in the biomass varied in response to CO2 levels in the cultivations. In general, higher CO2 concentrations (15 and 30%) favored the production of saturated and mono-unsaturated fatty acids, suitable as biodiesel feedstock, while drastically decreased the production of the polyunsaturated. (AU)

• Processo FAPESP: 18/22790-7 - Avaliação do potencial da produção de biopolímeros por bactérias metilotróficas
• Beneficiário: Elen Aquino Perpetuo
• Modalidade de apoio: Auxílio à Pesquisa - Programa BIOTA - Regular
• Processo FAPESP: 14/50279-4 - Brasil Research Centre for Gas Innovation
• Beneficiário: Julio Romano Meneghini
• Modalidade de apoio: Auxílio à Pesquisa - Programa Centros de Pesquisa em Engenharia