Endophytic bacteria and fungi as a source of polysaccharides: production and characterization techniques

Polymers, mainly polysaccharides, are a class of macromolecules that have a variety of structural and functional roles in biological systems. Recently, research on polysaccharides, especially exopolysaccharides (EPS) from microbial sources, has gained significant interest. These substances are valued for their biocompatibility, biodegradability, and wide range of applications across the pharmaceutical, biomedical, and industrial sectors. Endophytic microorganisms, which live inside healthy plant tissues, are a newly discovered sustainable source of exopolysaccharides. This article reviews research on endophytic bacteria and fungi that produce polysaccharides. The major focus is on summarizing the production and characterization techniques used. It includes extraction, purification, and structural analysis, including chromatographic, spectroscopic, and microscopic techniques. Additionally, tables summarizing features of polysaccharides from both bacterial and fungal endophytes, and a table on the characterization techniques and biological activities of these polysaccharides are included. By consolidating current insights and identifying existing gaps, this review seeks to enhance understanding of endophytic polysaccharides.