# Optimized Alkaline Hydrolysis for Recovering Ferulated Arabinoxylan Biopolymers from Maize Bran with Antioxidant Functionality

## TL;DR

This study optimizes a method to extract antioxidant-rich ferulated arabinoxylan biopolymers from maize bran using alkaline hydrolysis.

## Contribution

The study introduces an optimized alkaline hydrolysis method for efficiently extracting antioxidant-active ferulated arabinoxylans from maize bran.

## Key findings

- FAX yields ranged from 14.7 to 18.9% with high arabinose- and xylose-rich polymer content.
- Alkaline-extracted FAXs showed significantly higher antioxidant activity than free phenolics.
- FAXs exhibited high water-holding and emulsifying properties suitable for food applications.

## Abstract

Maize bran is an abundant cereal byproduct and a promising source of ferulated arabinoxylan biopolymers (FAXs). In this study, alkaline hydrolysis was optimized for FAX extraction from maize bran using a design-of-experiments approach evaluating alkali concentration, extraction time, and temperature. Purified FAXs were characterized for their chemical composition, phenolic and ferulic acid content, antioxidant activity, microstructure, and functional properties using GC–MS, HPLC, FT-IR, SEM, and standard antioxidant and functional assays. The FAX yields ranged from 14.7 to 18.9%, producing arabinose- and xylose-rich polymers (A/X ratio 0.68–0.74) with a high proportion of bound ferulic acid. Antioxidant assays (FRAP, ABTS, and DPPH) showed that alkaline-extracted and bound phenolic fractions exhibited substantially higher antioxidant capacity (p ≤ 0.05) than free phenolics, highlighting the importance of phenolic association with the arabinoxylan backbone. The FAX 3 extract also showed high activity in both the alkaline-extracted phenolic compounds (905.0 μg/g TE) and fraction II (286.5 μg/g TE), indicating that specific structural features may contribute to its bioactivity. In addition, FAXs demonstrated high water-holding capacity and favorable emulsifying properties. These results support the recovery of maize bran-derived FAXs as functional, antioxidant-active ingredients for food and related applications.