Celente, Gleison, de Cassia de Souza Schneider, Rosana, Julich, Jennifer, Medianeira Rizzetti, Tiele, Alcayaga Lobo, Eduardo and Sui, Yixing ORCID: 0000-0003-2646-5773 (2023) Life cycle assessment of microalgal cultivation medium: biomass, glycerol, and beta-carotene production by Dunaliella salina and Dunaliella tertiolecta. The International Journal of Life Cycle Assessment. ISSN 0948-3349 (Print), 1614-7502 (Online) (doi:https://doi.org/10.1007/s11367-023-02209-2)

Preview

PDF (Publisher VoR) 43708_SUI_Life_cycle_assessment_of_microalgal_cultivation_medium_biomass_glycerol_and_beta_carotene.pdf - Published Version Available under License Creative Commons Attribution. Download (2MB) | Preview

Abstract

Purpose
Dunaliella is a halophilic genus of microalgae with high potential in the global food market. The microalgal cultivation process contributes to not only economic impact but also environmental impact, especially regarding the artificial medium composition. In this context, a life cycle assessment was carried out to analyze the impacts associated with the components of the modified Johnson medium (MJM) and to predict the best scenarios to cultivate Dunaliella tertiolecta and Dunaliella salina for biomass, glycerol, and beta-carotene production.
Method
Two chains were analyzed separately: (1) Dunaliella salina (strain DF 15) cultivated in 8 scenarios combining different nitrogen (0.1 and 1.0 g L−1 KNO3) and magnesium (1.1–2.3 g L−1 MgCl2.6H2O) concentrations to produce biomass, glycerol, and beta-carotene and (2) Dunaliella tertiolecta (strain CCAP 19/30) cultivated in 5 scenarios combining different nitrogen (0.1 and 1.0 g L−1 KNO3) and salt (116.9–175.4 g L−1 sea salt) concentrations to produce biomass and glycerol. In addition, we evaluated the potential of cultivating these species to reduce the carbon footprint of the proposed scenarios.
Results and discussion
For D. salina, S5 (1 g L−1 KNO3, 1.1 g L−1 MgCl2.6H2O) had the lowest environmental damage for biomass (74.2 mPt) and glycerol production (0.95 Pt) and S3 (0.1 g L−1 KNO3, 1.9 g L−1 MgCl2.6H2O) for beta-carotene (3.88 Pt). T4 (1 g L−1 KNO3, 116.9 g L−1 sea salt) was the best for D. tertiolecta for biomass (74 mPt) and glycerol (0.49 Pt). “Respiratory inorganics,” “Non-renewable energy,” and “Global warming” were the most impacted categories. “Human health,” “Climate change,” and “Resources” had the highest share of all damage categories. All the scenarios presented negative carbon emission after proposing using brine as alternative salt source: S5 was the best scenario (− 157.5 kg CO2-eq) for D. salina and T4 for D. tertiolecta (− 213.6 kg CO2-eq).
Conclusion
The LCA proved its importance in accurately predicting the optimal scenarios for MJM composition in the analyzed bioproducts, as confirmed by the Monte Carlo simulation. Although the absolute values of impacts and productivity cannot be directly compared to large-scale cultivation, the validity of the LCA results at this scale remains intact. Productivity gains could outweigh the impacts of “surplus” MJM components. Our study showcased the potential of combining D. salina and D. tertiolecta cultivation with CO2 capture, leading to a more environmentally friendly cultivation system with a reduced carbon footprint.

Item Type:	Article
Uncontrolled Keywords:	life cycle assessment; Dunaliella salina; Dunaliella tertiolecta; modified Johnson medium; medium; optimization; Carbon footprint
Subjects:	G Geography. Anthropology. Recreation > GE Environmental Sciences Q Science > Q Science (General) Q Science > QH Natural history
Faculty / School / Research Centre / Research Group:	Faculty of Engineering & Science Faculty of Engineering & Science > School of Science (SCI)
Last Modified:	15 Aug 2023 12:32
URI:	http://gala.gre.ac.uk/id/eprint/43708

Actions (login required)

View Item

Downloads