Recent advances in Astragalus polysaccharides: Structural characterization, bioactivities and gut microbiota modulation effects

Background

Astragalus polysaccharides (APS) as the main active ingredient derived from Astragalus membranaceus proved to have remarkable health benefits. The diverse bioactivities of APS have also been extensively reported, making it a potential functional food ingredient and herbal formulations in functional food and medicinal fields to treat diseases and body disorders. Nevertheless, there is a lack of necessary analysis of the structure, biological activity and relationship between APS and gut microbiota.

Scope and approach

This review revisits the evidence-based information on the preparation, structure, biological activities and related mechanisms of APS. Emphasis is placed on the impact of APS on host health and gut microbiota.

Key findings and conclusions

The APS has a molecular weight range of 2.11–5020 kDa and exhibits various biological activities. Among them, those with moderate molecular weight range possess the strongest bioactivity. Meanwhile, APS can modulate the composition and structure of gut microbiota, improve intestinal barrier permeability, thus maintaining intestinal health. Additionally, APS and its metabolites can act with gut microbiota to mediate actions on immune cells (such as macrophages, dendritic cells, and lymphocytes), regulate immune responses and provide potential benefits to overall health. Exploring the structure, biological activity and connection between APS and gut microbiota can greatly promote the utilization of astragalus resources and provide new insights and methods for improving intestinal and host health.