Preparation of ferulic acid from corn bran: Its improved extraction and purification by membrane separation

摘要

Corn bran contains a high amount of ferulic acid. However, the separation and purification of ferulic acid from corn bran still encounter technical problems. In this research, ferulic acid was obtained from corn bran via membrane separation from hydrolysate treated with an alkaline-ethanol aqueous solution. The technology was optimised as follows. One weight of corn bran was extracted using 0.25 mol/L NaOH in 50% ethanol aqueous solution at 75 degrees C for 2 h. Filtrates were ultrafiltrated at room temperature using a membrane with 5000 Da molecular cut-off. Permeates with 91.8% recovery of ferulic acid were concentrated by nanofiltration using a membrane with 150 Da molecular cut-off. Ferulic acid crystal (8.47 g/kg corn bran) with 84.45% purity was obtained after the pH of the concentrate was adjusted to 2.0. The reducing sugars released from the alkaline-hydrolysed residue increased by 54.5% compared with the untreated corn bran after xylanase hydrolysis for 8 h. (C) 2013 The Institution of Chemical Engineers. Published by Elsevier B.V. All rights reserved.