Abstract
Microalgae cultivation is a promising alternative to traditional agriculture in arid—semi-arid areas. The aim of this study is to assess the viability of long-term cultivation of native Arthrospira platensis in Gran Canaria. Maximum culture productivity (0.08 g/L/day) and optimal concentration range (0.6–0.9 g/L) were firstly determined in 8000 L raceway under a greenhouse. Afterwards, a stable productivity of 0.06 g/L/day (6.0 g/m2/day) was obtained by reusing the culture medium during 26 days of cultivation, with consistent biomass biochemical composition. Outdoor temperature and daily solar irradiation ranged between 17.9–30.7 °C and 79.2–274.8 W/m2, while culture pH and salinity were in the range 9.42–10.77 and 11.2–14.9 g/L, respectively. Protein (>60%), potassium (1.8 g/100 g) and C-phycocyanin (7.2%) content is in the high-range of commercial Spirulina, which makes BEA 1257B promising for food and extraction of natural pigments/antioxidants. The dried biomass complies with international standards for human consumption, because of low heavy metal content and no pathogens presence. Product quality can be improved by reducing ash (≃12%) and sodium (1.5%) content through biomass washing optimization and/or further dewatering step. Other microorganisms can be prevented by high alkaline conditions and mild chemical treatments. These results pave the way for a sustainable microalgae-based blue bioeconomy in the Canary Islands.
Highlights
In a global scenario where Earth’s growing population is predicted to reach nearly 10 billion people by 2050, a 60% increment in the agricultural production demand in the 30 years is expected [1]
Our results suggest that year-round stable production of native A. platensis BEA 1257B in open ponds by recycling the culture medium is feasible, with valuable productivity (21.9 t/ha/year of dry biomass), consistent high quality and reproducibility of the biomass, and significant reduction of the water demand
The Canarian strain A. platensis BEA 1257B was cultivated in an 8000 L raceway under greenhouse conditions for approximately two months, in semi-continuous mode
Summary
In a global scenario where Earth’s growing population is predicted to reach nearly 10 billion people by 2050, a 60% increment in the agricultural production demand in the 30 years is expected [1]. Achieving agricultural sustainability in the coming decades, despite the growing competition for land, clean water and energy, and the changing climate conditions that harm traditional crops and future farming systems is an urgent issue to ensure global food supply [2]. The enhancement of extensive agriculture over the last decades has increased output productivities, but has generated drastic impacts on the environment [3]. This indicates the need to develop new agricultural strategies which support high biomass productivities while concomitantly mitigating environmental effects or even support environmental restoration [3], according to the concept of ecological sustainability in relation to business development [4]. CO2 from flue gas can be used as carbon source in the cultivation process [5,6]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
