Assessing the potential of fatty acids produced by filamentous fungi as feedstock for biodiesel production

ABSTRACT

Increased costs and limited availability of traditional lipid sources for biodiesel production encourage researchers to find more sustainable feedstock at low prices. Microbial lipid stands out as feedstock replacement for vegetable oil to convert fatty acid esters. In this study, the potential of three isolates of filamentous fungi (Mucor circinelloides URM 4140, M. hiemalis URM 4144, and Penicillium citrinum URM 4126) has been assessed as single-cell oil (SCO) producers. M. circinelloides 4140 had the highest biomass concentration with lipid accumulation of up to 28 wt% at 120 hr of cultivation. The profile of fatty acids revealed a high content of saturated (SFA) and monounsaturated fatty acids (MUFA), including palmitic (C16:0, 33.2–44.1 wt%) and oleic (C18:1, 20.7–31.2 wt%) acids, with the absence of polyunsaturated fatty acids (PUFA) having more than four double bonds. Furthermore, the predicted properties of biodiesel generated from synthesized SCOs have been estimated by using empirical models which were in accordance with the limits imposed by the USA (ASTM D6715), European Union (EN 14214), and Brazilian (ANP 45/2014) standards. These results suggest that the assessed filamentous fungus strains can be considered as alternative feedstock sources for high-quality biofuel production.

KEYWORDS:

• Biodiesel
• fatty acids
• filamentous fungi
• single cell oil

Acknowledgments

The authors gratefully acknowledge the financial support of Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) and Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq). Juan D. Rivaldi would especially like to thank the support of CAPES (Process PNPD 02565/09-9).

Additional information

Funding

This work was supported by the Coordenação de Aperfeiçoamento de Pessoal de Nível Superior [Grant Number Process Number PNPD-CAPES 20131746] and Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq). [Grant Number Process Number CNPq 404812/2013-9].