Extraction, purification, structural characterization, and biological activity of polysaccharides from Aralia: A review

Aralia Linn. Plants (ALPs) is a member of the Araliaceae family, a genus of more than thirty species, some plants of Aralia Linn are commonly used as herbal medicines. ALPs is commonly utilized for relieving the symptoms of neurasthenia, rheumatoid arthritis, etc. The principal extraction approaches of polysaccharides of ALPs (AEP) encompass water extraction, ultrasonic-assisted, compound enzyme and microwave-assisted. Various extraction approaches and extraction conditions will affect the extraction rate and purity of the AEP. AEP is mainly composed of arabinose (Ara), galactose (Gal), rhamnose (Rha), xylose (Xyl) and so on with different proportions of monosaccharides. AEP is one of the principal active components of ALPs, which has a variety of biological activities. Studies have shown that activities of AEP are anti-tumor, cardioprotective, hepatoprotective, anti-radiation, and hypoglycemic. One of the anti-tumor mechanisms of AEP is mitochondrial apoptosis pathway, and its regulatory process is described in detail. This review mainly summarizes the researches on extraction, separation, structural characterization and pharmacological activities of some AEP both the latest local and international in recent years. It lays a foundation for clinical safety application and the broadening of the application scope.