Procedia Chemistry 18 (2016) 147 – 154 1876-6196 © 2016 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/). Peer-review under responsibility of the organizing committee of the Molecular and Cellular Life Sciences: Infectious Diseases, Biochemistry and Structural Biology 2015 (MCLS 2015) doi:10.1016/j.proche.2016.01.023 Available online at www.sciencedirect.com ScienceDirect Molecular and Cellular Life Sciences: Infectious Diseases, Biochemistry and Structural Biology 2015 Conference, MCLS 2015 Deep Eutectic Solvent (DES) as a Pretreatment for Oil Palm Empty Fruit Bunch (OPEFB) in Sugar Production Nur Atikah Md Nor a , Wan Aida Wan Mustapha a , Osman Hassan a * a School of Chemical Sciences and Food Technology, Faculty of Science and Technology, Universiti Kebangsaan Malaysia (UKM), 43600 Bangi, Selangor, Malaysia Abstract Oil Palm Empty Fruit Bunch (OPEFB) was pretreated using Deep Eutectic Solvent (DES) at different parameters to enable a highest yield of sugar. DES is a combination of two or more cheap and safe components to form an eutectic mixture through hydrogen bond interaction, which has a melting point lower than that of each component. DES can be used to replace Ionic Liquids (ILs), which are more expensive and toxic. In this study, OPEFB was pretreated with DES mixture of choline chloride : urea in 1:2 molar ratio. The pretreatment was performed at temperature 110ºC and 80ºC for 4 hours and 1 hour. Pretreatment A (110ºC, 4 hours), B (110ºC, 1 hour), C (80ºC, 4 hours) and D (80ºC, 1 hour). Enzymatic hydrolysis was done by using the combination of two enzymes, namely, Cellic Ctec2 and Cellic Htec2. Morphology surface of OPEFB is observed under Scanning Electron Microscopy (SEM). The treated fiber is tested for crystallinity using XRD and functional group analysis using FTIR, to check the effect of the pretreatment on the fiber and compared it with the untreated fiber. From XRD analysis, DES successfully gave an effect towards degree of crystallinity of cellulose. Pretreatment A and B successfully reduce the percentage of crystallinity while pretreatment C and D increased the percentage of crystallinity. From FTIR analysis, DES can expose the structure of cellulose even though the functional group of lignin and hemicellulose were still present. Upon enzymatic hydrolysis, DES-treated fiber successfully produced sugar but not significantly when compared with raw. Pretreatment A, B, C and D produced glucose at the amount of 60.47 mg/ml, 66.33 mg/ml, 61.96 mg/ml and 59.12 mg/ml respectively. However, pretreatment C gave the highest xylose (70.01 mg/ml) production compared to other DES pretreatments. © 2015 The Authors. Published by Elsevier B.V. Peer-review under responsibility of the organizing committee of the Molecular and Cellular Life Sciences: Infectious Diseases, Biochemistry and Structural Biology 2015 (MCLS 2015). Keywords: Deep eutectic solvent; oil palm empty fruit bunch; pretreatment; crystallinity * Corresponding author. Tel.: - ; fax: -. E-mail address: drosmanhassan@gmail.com © 2016 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/). Peer-review under responsibility of the organizing committee of the Molecular and Cellular Life Sciences: Infectious Diseases, Biochemistry and Structural Biology 2015 (MCLS 2015)