Cultivation of Limnospira maxima under extreme environmental conditions in Saudi Arabia: Salinity adaptation and scaling-up from laboratory culture to large-scale production

• Published in: Bioresource technology 2024-08, Vol.406, p.131089, Article 131089
• Main Authors: González-Portela, Ricardo E., Romero-Villegas, Gabriel I., Kapoore, Rahul V., Alammari, Zain M., Malibari, Raghdah A., Shaikhi, Ali Al, Al Hafedh, Yousef, Aljahdali, Abdulaziz H., Banjar, Rana E., Mhedhbi, Emna, Filimban, Akram, Padri, Mohamad, Fuentes-Grünewald, Claudio
• Format: Article
• Language: English
• Subjects: Biomass yield; Cyanobacteria; Desert adaptation; Microalgae farming; Sustainability
• ISSN: 0960-8524; 1873-2976; 1873-2976
• DOI: 10.1016/j.biortech.2024.131089

[Display omitted] •Limnospira maxima was cultivated in harsh environment of summer in Saudi Arabia.•Natural evaporation was proven to adapt the strain into hypersaline seawater.•Biomass productivity reached 60 g m2/day with more than 40 % protein content.•Uncoiled and straightened algal filaments were found during the adaptation process.•Direct sunlight exposure initiated the color change in the outdoor cultivation. Limnospira maxima has been adapted to grow in high salinity and in an economically alternative medium using industrial-grade fertilizers under harsh environmental conditions in Saudi Arabia. A sequence of scaling-up processes, from the laboratory to large-scale open raceways, was conducted along with gradual adaptation to environmental stress (salinity, light, temperature, pH). High biomass concentration at harvest point and areal productivity were achieved during the harsh summer season (1.122 g L−1 and 60.35 g m−2 day−1, respectively). The average protein content was found to be above 40 % of dry weight. Changes in the color and morphological appearance of the L. maxima culture were observed after direct exposure to sunlight in the outdoor raceways. These results demonstrate a successful and robust adaptation method for algal cultivation at outdoor large-scale in harsh environment (desert conditions) and also prove the feasibility of using hypersaline seawater (42 g kg−1) as an algal growth medium.