Reaction optimization of Aspergillus niger α-L-arabinofuranosidase for improved arabinose production from kenaf stem

Abstract

There are abundant of lignocellulosic biomass readily available with varying compositions. Kenaf (Hibiscus cannabinus) is one of this lignocellulosic biomass that has a high content of hemicellulose. This particular hemicellulose is composed of high arabinoxylan, which is a xylan backbone with arabinofuranosyl branches. In order to hydrolyze arabinoxylan, a branching enzyme is needed. Therefore, α-L-arabinofuranosidase from Aspergillus niger ATCC120120 (AnabfA) was used to hydrolyzed pre-treated kenaf and the reaction conditions were optimized using central composite design (CCD) to produce a significant amount of arabinose. There were 20 experiments conducted with 1.68 star points and 6 replicates at the centre points. The reaction conditions that were optimized are enzyme loading, substrate concentration and reaction time in which resulted with 88 U AnabfA activity, 0.9% (w/v) and 48 h, respectively. These optimized conditions managed to increase the yield of arabinose with 47.17 mg/g arabinose produced.