Green Downstream Processing Method for Xylooligosaccharide Purification and Assessment of Its Prebiotic Properties

Area of Science:

• Biomass valorization and carbohydrate chemistry
• Green chemistry and sustainable processing
• Food science and nutraceutical development

Background:

• Lignocellulosic biomass hydrolysis yields xylooligosaccharides (XOS) contaminated with lignin derivatives and inhibitors (furfural, HMF, acetic acid).
• Existing purification methods like membrane filtration and activated charcoal treatment have limitations in efficiency and inhibitor removal.
• Development of cost-effective and environmentally friendly purification techniques for XOS is crucial for its industrial application.

Purpose of the Study:

• To develop and evaluate a novel graphene oxide-mediated purification (GOMP) method for XOS from ozone-assisted autohydrolysis of wheat bran.
• To compare the efficacy of GOMP with conventional purification techniques in terms of XOS recovery and inhibitor removal.
• To assess the prebiotic potential of purified XOS fractions.

Main Methods:

• Ozone-assisted autohydrolysis of wheat bran to obtain hydrolysate rich in XOS and inhibitors.
• Application of graphene oxide-mediated purification (GOMP) for selective adsorption of inhibitors.
• Characterization of XOS composition (DP2-6) and evaluation of prebiotic activity with probiotic cultures.

Main Results:

• GOMP achieved high XOS recovery (73.87%) and near-complete removal of inhibitors (furfural 85.42%, HMF 87.38%, acetic acid 84.0%).
• GOMP significantly outperformed membrane purification (44.07% recovery) and was comparable to activated charcoal (72.76% recovery) with superior inhibitor removal.
• Purified XOS fractions (DP2-6) demonstrated prebiotic effects, stimulating probiotic growth and producing short-chain fatty acids.

Conclusions:

• Graphene oxide-mediated purification (GOMP) is an efficient, single-step, and eco-friendly method for purifying xylooligosaccharides from lignocellulosic biomass.
• GOMP offers a viable alternative to conventional methods, providing high XOS recovery and effective inhibitor removal.
• The purified XOS exhibits significant prebiotic properties, highlighting its potential for use in functional foods and supplements.