Critical review on the research of chemical structure, bioactivities, and mechanism of actions of Dendrobium officinale polysaccharide

Dendrobium officinale (Tie-Pi-Shi-Hu) is a precious traditional Chinese medicine (TCM). The principal active components are polysaccharides (DOP), which have a high potency in therapeutic applications. However, limitations in structure analysis and underlying mechanism investigation impede its further research. This review systemically and critically summarises current understanding in both areas, and points out the influence of starch impurities and the role of gut microbiota in DOP research. As challenges faced in studying natural polysaccharide investigations are common, this review contributes to a broader understanding of polysaccharides beyond DOP. •The starch-like impurities influence the structure analysis of DOP.•The oligomer-based approach is useful to solve problems in typical methods.•In vitro studies on DOP do not reflect its action in vivo.•DOP may exert its beneficial effects by interaction with gut microbiota.