The optimum conditions for the production of L-arabinose from debranched arabinan were determined to be pH 6.5, 75 degrees C, 20 gl(-1) debranched arabinan, 42 U ml(-1) endo-1,5-alpha-L-arabinanase, and 14U ml(-1) alpha-L-arabinofuranosidase from Caldicellulosiruptor saccharolyticus and the conditions for sugar beet arabinan were pH 6.0, 75 degrees C. 20 gl(-1) sugar beet arabinan, 3 U ml(-1) endo-1,5-alpha-L-arabinanase, and 24 U ml(-1) alpha-L-arabinofuranosidase. Under the optimum conditions, 16 gl(-1) L-arabinose was obtained from 20 gl(-1) debranched arabinan or sugar beet arabinan after 120 min, with a hydrolysis yield of 80% and a productivity of 8 gl(-1) h(-1). This is the first reported trial for the production of L-arabinose from the hemicellulose arabinan by the combined use of endo- and exo-arabinanases. (C) 2010 Elsevier Ltd. All rights reserved.