Extraction methods, structural features and pharmacological effects of polysaccharides from Dendrobium nobile: A...

Dendrobium nobile Lindl. is a precious medicinal and edible plant with exceptional nutritional and pharmaceutical value. In traditional Chinese medicine, it is known for its efficacy in nourishing the stomach, promoting fluid production, nourishing yin, and clearing heat, with a millennia-long usage history. Extensive studies have confirmed that Dendrobium nobile polysaccharides (DNPs) are a critical bioactive macromolecular component in it, exhibiting diverse biological activities. However, the current literature lacks a comprehensive review of DNPs, which may hinder their development and application.

This review aims to offer a systematical summary of the extraction, purification, detailed structural features, various pharmacological activities, and action mechanisms of DNPs. It further explores the potential applications of Dendrobium nobile, thereby laying a solid foundation for the development and utilization of DNPs.

To conduct a comprehensive search, the specific term "Dendrobium nobile polysaccharides" was searched across several key academic databases, including PubMed, Google Scholar, Web of Science, and the China National Knowledge Infrastructure.

Currently, over 40 polysaccharides have been isolated from Dendrobium nobile. These DNPs are primarily extracted using methods such as hot water extraction, enzyme-assisted extraction, ultrasonic-assisted extraction, and microwave-assisted extraction. Subsequent purification procedures include decolorization, deproteinization, removal of other small molecular substances, and chromatographic separation to yield homogeneous products. Variations in extraction and purification methods contribute to the diverse chemical compositions and structures of DNPs, which in turn confer a wide range of pharmacological activities. These mainly include antioxidant, neuroprotective, antidiabetic, hepatoprotective, anti-inflammatory, antitumor, and immunomodulatory properties.

This review comprehensively summarizes research progress on DNPs, covering extraction, purification, structural properties, pharmacodynamic effects, action mechanisms, and structural modifications. It also analyzes structure-bioactivity relationships, toxicological effects, and industrial potential prospects, identifies current research gaps, and proposes future research directions. Overall, this review provides a theoretical basis for further developing and utilizing DNPs in pharmaceutical and health food fields.