Potential biodiesel production from Brazilian plant oils and spent coffee grounds by Beauveria bassiana lipase 1 expressed in Aspergillus nidulans A773 using different agroindustry inputs

This paper describes the obtaining of fatty acids ethyl esters from Acai (Euterpe oleracea Martius), Buriti (Mauritia flexuosa) and spent coffee grounds oils using a Beauveria bassiana lipase expressed in Aspergillus nidulans, which gene was cloned in pExpyr vector. Carbon sources were tested to enhance recombinant lipase secretion. Cassava peels, corn meal, corn syrup, sorghum seed and wheat bran induced higher lipase activity. Monosaccharides, when combined to previously cited carbon sources, interfered at lipase production: fructose and glucose enhanced lipase production, especially on sorghum seed and wheat bran cultures; while xylose diminished its production. Lipase was immobilized on hydrophobic resins, and derivatives were characterized using pNPP transesterification with ethanol as co-substrate. Sepabead-C18 derivative demonstrated as better pNPP transesterification catalyzer, being 2-fold higher than butyl derivative. The Sepabead-C18 derivative was biochemically characterized using different temperatures and solvents. The transesterification of Acai, Buriti and coffee spent grounds oils were performed with cyclohexane, and the product content was quantified using gas-chromatography as 17.1%, 5.0%, and 3.4%, respectively. The results demonstrated the potential of immobilized heterologous lipases to produce ethyl ester from Brazilian natural oils and a common food waste. This work will improve the enzymatic methodologies for biodiesel industry. (C) 2020 Elsevier Ltd. All rights reserved.