# Hydrogel Design Based on Bacterial Exopolysaccharides: The Biomedical Promise of Levan

## TL;DR

This paper reviews how levan, a bacterial exopolysaccharide, can be used to create advanced hydrogels with biomedical applications like drug delivery and tissue engineering.

## Contribution

The paper provides a comprehensive overview of levan-based hydrogels, emphasizing their design strategies and biomedical promise.

## Key findings

- Levan-based hydrogels offer adjustable mechanical and biological properties.
- Levan's biocompatibility and bioactivity make it suitable for drug delivery and tissue engineering.
- Design strategies include chemical modification and composite formation to tailor hydrogel properties.

## Abstract

Bacterial exopolysaccharides have emerged as versatile biopolymers for the design of advanced hydrogels with adjustable physico-chemical, mechanical, and biological properties. Among these, levan, a fructose-based exopolysaccharide synthesized by various microbial species, has attracted increasing attention due to its unique structural features, high biocompatibility, and inherent bioactivity. This review provides a comprehensive overview of hydrogel systems derived from bacterial exopolysaccharides, with a particular focus on levan-based hydrogels. We discuss the molecular structure, synthesis pathways, and physico-chemical characteristics of levan that underpin its hydrogel-forming ability. Emphasis is placed on design strategies, including chemical modification, crosslinking approaches, and composite formation, that enable fine-tuning of mechanical strength, swelling behavior, and degradation kinetics. This review further highlights biomedical applications of levan-based hydrogels, encompassing drug delivery, wound healing, rejuvenation, tissue engineering, regenerative medicine, and bioprinting, while addressing current limitations and future research directions. By elucidating the structure–function relationships and emerging fabrication methodologies, this review underscores the biomedical promise of levan as a sustainable and functional biopolymer for next-generation hydrogel technologies.