Abstract
Ionic liquids (ILs) are regarded as green solvents and have demonstrated ability in the solvation of lignocellulosic material, thus promoting its enzymatic hydrolysis by cellulases. In this study, cellulase (PKC-Cel) obtained from Trichoderma reesei (RUTC30) through fermentation displayed good stability in choline acetate [Cho]OAc, a biodegradable IL. Empty fruit bunches (EFB) were subjected to single-step hydrolysis in an IL-enzyme system. Response surface methodology was employed to maximize ethanol production. Three parameters were optimized, namely sugar loading, inoculum concentration, and agitation. The distilled ethanol purity was 98.6% (v/v). The ethanol yield was 87.94% of the theoretical yield, which was 0.275 g ethanol g−1 EFB. In comparison, the non-IL system produced 0.127 g g−1 EFB. The yield coefficients ,
, and
were 0.552, 0.148, and 3.69 g g−1. The specific growth rate
was determined to be 0.264 h−1 and the
was 0.777 h−1.
Acknowledgements
This project is funded by FRGS-13-088-0329. The authors are grateful to the Department of Biotechnology Engineering and International Institute for Halal Research and Training (INHART) in IIUM and Centre of Research in Ionic Liquids (CORIL) in University Technology Petronas for providing the lab facilities. Our gratitude is also extended to the West Oil Mill, Sime Darby Plantation for providing the experimental biomass samples for this project. We would like to thank Editage (www.editage.com) for English language editing.
Declaration of interest statement
The authors declare no financial or commercial conflict of interest.