# Impact of extraction methods on soybean hull polysaccharides: structure and functional properties analysis

## TL;DR

This study examines how different extraction methods affect the structure and functional properties of soybean hull polysaccharides.

## Contribution

The study reveals how extraction methods influence the structural and functional properties of soybean hull polysaccharides.

## Key findings

- Microwave pretreatment increases SHP yield and carbohydrate content.
- MS-SHP shows superior emulsifying activity and stability due to its HG-type structure.
- Extraction methods significantly alter SHP's viscosity and monosaccharide content.

## Abstract

Soybean hull polysaccharides (SHP) exhibit diverse functional properties, yet the influence of extraction methods on their structure–function relationships remains unclear. This study investigated microwave-assisted extraction (M), extractant-assisted (citric acid, MC; sodium citrate, MS), and extractant-enzyme (cellulase/pectinase)-assisted (MCC, MCP, MSC, MSP). The results show that the M have a relatively high extraction yield (3.39 %) and carbohydrate content (92.64 %) compared with others. MS have the highest glucuronic acid content (41.60 %). Structural analysis revealed that M, MC, MCC, and MCP produced RG-I-type pectins with high branching degrees (12.85–16.71), whereas MS, MSP, and MSC generated predominantly linear homogalacturonan (HG) domains (linearity: 1.51–1.81). Moreover, Na+ combined with higher HG domains reduced electrostatic repulsion and promoted polysaccharide alignment at the oil–water interface, leading to superior emulsifying activity (277.48 m2/g) and stability (6232.07 min) in MS. These findings clarify SHP structure–function relationships and provide guidance for tailoring polysaccharide properties through optimized extraction strategies.

Investigating the effects of different extraction methods on the physicochemical properties, structural characteristics, and functional properties of soybean hull polysaccharides.Unlabelled Image

•Microwave pretreatment enhances the yield and carbohydrate content of SHP.•Extraction methods significantly influence SHP's viscosity, monosaccharide content, and structure.•MS-SHP exhibits superior emulsifying activity and emulsion stability.•MS-SHP has primarily HG-type structural domains, while MC-SHP is mainly RG-I type.

Microwave pretreatment enhances the yield and carbohydrate content of SHP.

Extraction methods significantly influence SHP's viscosity, monosaccharide content, and structure.

MS-SHP exhibits superior emulsifying activity and emulsion stability.

MS-SHP has primarily HG-type structural domains, while MC-SHP is mainly RG-I type.