Cultivation of different microalgae with pentose as carbon source and the effects on the carbohydrate content

ABSTRACT

In the search for alternative carbon sources for microalgae cultivation, pentoses can be considered interesting alternatives since the most abundant global source of renewable biomass is lignocellulosic waste, which contains significant quantities of pentoses. However, the use of pentoses (C5) in the cultivation of microalgae is still not widely studied and only recently the first metabolic pathway for pentose absorption in microalgae was proposed. So, the objective of this work was to evaluate if the use of pentoses affects the growth and carbohydrates content of Chlorella minutissima, Chlorella vulgaris, Chlorella homosphaera and Dunaliella salina. The kinetic parameters, carbohydrate and protein content and the theoretical potential for ethanol production were estimated for all strains. The highest cellular concentrations (1.25 g L⁻¹) were obtained for D. salina with 5% of pentoses. The addition of pentoses leads to high levels of carbohydrates for C. minutissima (58.6%) cultured with 5% of pentoses, and from this biomass, it is possible to determine a theoretical production of ethanol of 38 mL per 100 g of biomass. The pentoses affect the growth and the biomass composition of the studied strains, generating biomass with potential use for bioethanol production.

KEYWORDS:

• Carbohydrates
• carbon source
• Chlorella
• Dunaliella
• microalgae
• pentoses

Disclosure statement

No potential conflict of interest was reported by the authors.

ORCID

Jorge Alberto Vieira Costa http://orcid.org/0000-0001-8042-7642

Additional information

Funding

The authors are grateful to CAPES (Coordination for the Improvement of Higher Education Personnel) for the financial support that enabled this research.