Research progress on extraction, purification and pharmacological action of Rehmannia glutinosa polysaccharides

Abstract

Rehmannia glutinosa polysaccharide (RGP) is one of the main active ingredients of traditional Chinese medicine Dihuang (Rehmanniae Radix), mainly composed of glucose, rhamnose, mannose and other monosaccharides. There are many extraction methods of RGP. Different extraction methods have their unique advantages and affect the yield of RGP. Purification is an indispensable step to obtain RGP. After removing protein, pigment and other operations, the purity of RGP can be guaranteed, making its follow-up study more accurate. RGP and its derivatives have a variety of pharmacological functions such as immune regulation, neuromodulation, antioxidant, anti-inflammatory, anti-tumor, and treatment of diabetes, and have potential medicinal value. In this paper, the research progress of extraction and purification methods, pharmacological activities and carrier application of RGP were reviewed, which provided a basis for further research of RGP and its derivatives.