Extraction of polysaccharides from edible mushrooms: Emerging technologies and recent advances

Mushroom-derived polysaccharides (especially beta-glucans) are gaining much interest from researchers and industries recently due to their antioxidant, antitumor, immune-modulating activities, and other health benefits. Besides conventional extraction methods, a wide range of advanced extraction technologies is available nowadays for the recovery of these bioactive ingredients from mushrooms, such as ultrasonic-assisted extraction (UAE), microwave-assisted extraction (MAE), enzyme-assisted extraction (EAE), ultrasonic-microwave synergistic extraction (UMSE), subcritical water extraction (SWE), pulsed electric field-assisted extraction (PEFAE), aqueous two-phase extraction (ATPE), integrated extraction techniques, and other novel extraction technologies. This review describes the background of edible mushrooms, followed by the structural characteristics and biological activities of mushroom-derived polysaccharides. Then, the recent developments in the technologies used for the extraction of mushroom polysaccharides are discussed and summarized, together with their strengths and limitations as well as the underlying mechanisms. Finally, these advanced extraction techniques are compared and critically analyzed. Future outlook has also been proposed.