Advancements in novel polysaccharide analysis: Emerging spectral technology approaches

Polysaccharides are essential components of cells and significantly influence the growth, development, and functional regulation of organisms. Traditional detection methods such as chemical analysis and chromatography are often highly destructive to samples, cost-ineffective, inefficient, labor intensive, and involve reagents that can pose health to operators. In contrast, spectroscopic technology, particularly vibrational spectroscopy, has emerged as a safe, reliable and time-reducing method for the assessment of polysaccharide quality and safety. This review summarizes and compares the latest developments and applications of various spectral techniques, including near-infrared spectroscopy (NIRS), mid-infrared spectroscopy (MIRS), Raman, terahertz (THz) spectroscopy and hyperspectral imaging (HSI) in the quality analysis of polysaccharides from both quantitative and qualitative perspectives. Spectroscopic techniques are less commonly used for qualitative analysis of polysaccharides than quantitative methods in currently research progress. NIRS, MIRS, and HSI are key in assessing the quality of extracted and cell wall polysaccharides, while THz spectroscopy is valuable for elucidating the crystallinity of starch and cellulose. In qualitative analysis, NIRS and MIRS identify functional groups, while Raman spectroscopy adeptly monitors structural changes in extracted polysaccharides of cell wall. THz spectroscopy are correlated with changes in crystallinity via changes in signal, and is in the early stages of development. HSI facilitates the visualisation of structure and spatial distribution. Despite certain limitations, vibrational spectroscopy shows strong potential in both quantitative and qualitative polysaccharide analysis. • Quantitative polysaccharide studies are more prevalent than qualitative ones. • Raman monitors changes in cell wall polysaccharide composition and structure. • HSI enables rapid classification of polysaccharide habitats. • THz-TDS is still in the early stages of development for polysaccharide analysis. • Chemometrics enhance the efficiency and accuracy of spectroscopic analyses.