Astragali Radix (Huangqi): Extraction Techniques, A Promising Edible Immunomodulatory Herbal Medicine, and Biological Activity

Astragali Radix (AR) is one of the well-known traditional Chinese medicines with a long history of medical use and a wide range of clinical applications. AR contains a variety of chemical constituents which can be classified into the following categories: polysaccharides, saponins, flavonoids, amino acids, and trace elements. There are several techniques to extract these constituents, of which microwave-assisted, enzymatic, aqueous, ultrasonic and reflux extraction are the most used. Several methods such as spectroscopy, capillary electrophoresis and various chromatographic methods have been developed to identify and analyze AR. Meanwhile, this paper also summarizes the biological activities of AR, such as anti-inflammatory, antioxidant, antitumor and antiviral activities. It is expected to provide theoretical support for the better development and utilization of AR. The potential pharmaceutical properties of calycosin in the treatment of tumors, inflammation, stroke, and cardiovascular diseases have gained increasing attention in the recent years. The literature survey showed that calycosin exhibits promising effects for the treatment of several diseases and that these effects may be due to its isoflavonoid and phytoestrogenic properties. The effects of calycosin most likely result from its interaction with the ER receptors on the cell membrane and the modulation of the MAPK signaling pathway. Calycosin exhibits great potential as a therapeutic drug and may be a successful example of the standardization and modernization of traditional Chinese herbal medicine.