Investigation of commercial enzyme preparations for selective release of arabinose from corn fibre

BACKGROUND: Lignocellulosic materials have great potential in the production of L‐arabinose in a new cost‐effective way. Selective enzymatic liberation of L‐arabinose from agricultural residues could be a promising method if purification of specific enzymes and extraction of pure polysaccharides could be omitted from the process. To achieve this goal, investigation of commercial multi‐component enzyme preparations for selective release of L‐arabinose from destarched corn fibre and soaking in aqueous ammonia (SAA) pretreated destarched corn fibres were performed. RESULTS: Hemicellulase NS22002 (Novozymes) has a relative xylanase activity of 1% (of measured highest) and 9%, and a relative arabinoxylan‐arabinofuranohydrolase (AX‐AFH) activity of 71% and 100% at pH 3 and 4, respectively. At pH 6 its relative xylanase and AX‐AFH activities are 93% and 52%, respectively. Hydrolyses of SAA pretreated destarched corn fibre with Hemicellulase NS22002 at pH 4 and 6 resulted in a large amount of hemicellulosic oligomers, considerable amount of monomer arabinose and negligible amount of monomer xylose and galactose in the supernatants. During the hydrolysis at pH 3 monomer sugars were not released and low amounts of hemicellulosic oligomers were solubilised. CONCLUSION: SAA pretreatment has been found to be an appropriate method to make the structure of destarched corn fibre accessible for hemicellulose‐degrading enzymes. Hemicellulase NS22002 has high endo‐xylanase activity over a broad pH range, and its α‐L‐arabinofuranosidase can release arabinose from solubilised hemicellulosic oligomers derived from corn fibre. Enzymatic hydrolysis of SAA pretreated destarched corn fibre using Hemicellulase NS22002 is suitable to solubilise the hemicellulose fraction, however it cannot selectively release arabinose monomers. © 2014 Society of Chemical Industry