A review of polysaccharides from Ganoderma lucidum: Preparation methods, structural characteristics, bioactivities, structure-activity relationships and potential applications.

Ganoderma lucidum (G. lucidum), commonly known as "fairy grass", is a saprophyte fungus belonging to the Polyporaceae family with a lengthy history of use as a food ingredient and traditional medicine in China. G. lucidum is abundant in diverse chemical compounds that encompass polysaccharides, alkaloids, steroids, terpenoids, proteins, as well as amino acids. Among these, polysaccharides as the main active ingredients prepared from G. lucidum have exhibited a multitude of biological activities, such as anti-tumor effect, antioxidant activity, antidiabetic effect, anti-inflammatory effect, immune regulation and so forth. The main methods for extracting GLPs are hot water extraction, ultrasound-assisted extraction, microwave-assisted extraction and enzyme-assisted extraction. The research on GLPs poses challenges, especially in optimizing extraction and purification processes to enhance the yield and preserve the structural characteristics. Furthermore, it remains ambiguous whether the bioactivities of GLPs are closely related to their extraction methods and structural characteristics, necessitating further exploration and elucidation of the structure-activity relationships. This review comprehensively and systematically outlines an overview of the preparation methods, structural characteristics, bioactivities, structure-activity relationships and potential applications of GLPs. The review emphasizes their therapeutic potential and health functions, providing a reference for further exploitation and application in various fields of GLPs.