Effects and mechanism of traditional Chinese medicine processing techniques on physicochemical properties, structure, and biological activities of polysaccharides: A review

This article systematically reviews the effects of various processing methods on the physicochemical properties, structure and biological activities of polysaccharides. Studies have demonstrated that processing methods can significantly alter the sugar content, molecular weight, monosaccharide composition, and structural characteristics of polysaccharides, thereby influencing their biological activities. Processing techniques in Traditional Chinese Medicine (TCM), such as steaming, brewing, and stewing, have been shown to reduce the sugar content of polysaccharides. In contrast, factors such as alcohol, cellulase, and high temperature are known to regulate the molecular weight of polysaccharides. Different processing methods significantly affect the monosaccharide composition and molar ratio, which are closely related to the Maillard reaction. Furthermore, the polysaccharide chain structure undergoes considerable alterations during processing, which in turn influences its biological activities. Several studies have reported that processing methods can enhance the biological activities of polysaccharides, including antioxidant, immune-regulatory, prebiotic, anti-inflammatory, and antitumor properties. However, TCM processing methods are not without limitations and require further exploration of the “process-structure-mechanism”chain to provide theoretical and technical support for their modernization. Current studies lack standardized processing protocols and in-depth mechanistic evidence in vivo, hindering clinical translation. Future work should optimize the integration of traditional processing and green extraction, clarify structure-activity relationships, and validate efficacy and safety in clinical settings for rational application. • Physicochemical properties of Polysaccharides were altered by TCMs processing methods, then enhancing their bioactivity. • Heating and auxiliary materials were considered as key factors of polysaccharide properties and activities in TCMs processing. • The potential mechanisms (Maillard reaction, structural isomerization, aggregation) were hypothesized in TCMs processing. • Future research focus: structure-activity correlations, standardized methods, and control of potential toxic by-products, etc.