Investigation of selective arabinose release from corn fibre by acid hydrolysis under mild conditions

Abstract

BACKGROUND The high cost of pure arabinose has resulted in a growing demand to develop new cost‐effective methods of arabinose production from lignocellulosic and pectin‐rich materials. Corn fibre is an inexpensive by‐product of the corn wet‐milling process, and is a promising raw material for producing arabinose and other value‐added products. In this study fast dilute sulphuric acid hydrolysis of corn fibre was investigated for selective arabinose solubilization. Acid concentration and reaction time of hydrolysis of destarched ground corn fibre and raw corn fibre were 0.25–5 w/w% at 5–15 min and 0.25–1.25 w/w% at 25–75 min, respectively. Results were evaluated statistically and model equations were developed to predict the yields of sugars. RESULTS In the case of raw corn fibre the most favourable conditions were 1.1 w/w% sulphuric acid concentration and 51 min reaction time at 90°C, where a total arabinose yield of 75.9% was achieved with satisfactory selectivity. In the case of destarched ground corn fibre at a sulphuric acid concentration of 4.6 w/w%, a reaction time of 5 min and a temperature of 90°C, a total arabinose yield of 80.5% could be achieved with satisfactory selectivity, according to the model equations. CONCLUSION Arabinose‐rich liquid fractions were produced by mild sulphuric acid treatments of corn fibre. Based on the models developed the mono‐ and oligosaccharide contents of the hydrolysates can be controlled under the conditions investigated. © 2014 Society of Chemical Industry

Integrated Process of Arabinose Biopurification and Xylitol Fermentation Based on the Diverse Action of Candida boidinii

“…In the first step of the fractionation, corn fibre was treated under mild acidic conditions to solubilise the starch content and liberate most of the arabinose. 14 After the first hydrolysis, a considerable amount of oligosaccharides was obtained in the supernatant, thus an oligomer hydrolysis step was required to recover the sugars in monomeric form (Fig. 1).…”

“…6 The relatively high cost of gum arabic and the expensive purification steps result in the high cost of pure arabinose, 11 which has evoked an increasing research effort to develop new cost-effective methods of arabinose production from agro-residues rich in hemicellulose or pectin, for example from sugar beet pulp, 11 corn hull, 12 xylose-mother liquor, 6 wheat bran 13 and corn fibre. 14 Biopurification of hemicellulosic hydrolysate is an interesting and inexpensive strategy to produce a pure arabinose solution through the depletion of other sugars (e.g. glucose, xylose, galactose) using the adequate microorganisms.…”

Optimised Fractionation of Brewer’s Spent Grain for a Biorefinery Producing Sugars, Oligosaccharides, and Bioethanol

“…Concentrations of glucose, xylose, arabinose, ethanol, acetic acid, formic acid, 5hydroxymethyl-furfural (HMF), and furfural were quantified by high-performance liquid chromatography (HPLC) with refractive index detection. Separation was achieved on BioRad (Hercules, CA, USA) Aminex HPX-87H (300 × 7.8 mm) column equipped with Micro-Guard Cation H+ Refill Cartridge (30 × 4.6 mm) guard column, heated at 65 • C, using 5 mmol/L sulphuric acid at a flow rate of 0.5 mL/min [43]. Xylooligosaccharides were analysed by thin layer chromatography (TLC) according to the method detailed by Ontañon et al [47].…”

“…The dry content of BSG was measured by rapid moisture analyser (Precisa XM 60). The glucan, xylan, arabinan and Klason-lignin contents were analysed by using the NREL (National Renewable Energy Laboratory) method [42] with minor modifications detailed by Fehér et al [43]. The starch content was determined according to the method described by Bedő et.al [44].…”

“…The reaction time (10, 30, 50 min) and the sulphuric acid concentration (0.5, 1.25, 2.0 w/w%) were varied according to a full factorial experimental design. The range of the reaction time and sulphuric acid concentration were determined according to preliminary tests and previous studies [43,44]. Hydrolyses occurred at 90 • C reaction temperature in water bath without agitation.…”