by Eric Brand

The issue of substitute species of common medicinals is an ongoing theme here at the blog. In different Chinese regions, we see a variety of local substitutions and regional preferences, and if one extends the discussion to Japan and Korea, we can see a tremendous amount of variation in the plants used. For example, even the simple formula Si Wu Tang (Four Substances Decoction) has two items (Dang Gui and Chuan Xiong) that have different source plants listed in the official Pharmacopoeias of China, Japan, and Korea.

Many readers of our blog began their studies over a decade ago, and back then most English books listed the Latin Pharmaceutical name of Huang Qi as Radix Astragali seu Hedysari. Similarly, previous editions of many Chinese source texts also listed both astragalus and hedysarum as official sources of Huang Qi. However, if we look at current English books and the latest editions of many Chinese source texts, we now often see that astragalus and hedysarum are given separate entries, and the common pharmaceutical name of Huang Qi is now simply Radix Astragali.

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Huang Qi technically refers to astragalus, specifically the root of either Astragalus membranaceus (Fisch.) Bge. var. mongholicus (Bge.) Hsiao or Astragalus membranaceus (Fisch.) Bge. The root of Hedysarum polybotrys Hand. –Mazz. is officially known as Hong Qi. The two are also commonly differentiated by the names Bei Qi (astragalus) and Jin Qi (hedysarum). In terms of their TCM actions, the two are regarded as identical, but they come from different plants and have different chemical constituents.

In the U.S., astragalus is the most common source of Huang Qi. Astragalus is also the most common source of Huang Qi in mainland China. However, hedysarum is much more commonly used than astragalus in Taiwan, and it is estimated that over 90% of the product sold as Huang Qi in Taiwan is actually hedysarum.

In 1997, Taiwan imported 3,149,377 kilos of “Huang Qi.” The vast majority of this is actually hedysarum rather than astragalus. In fact, several experts at Taiwan’s granule factories mentioned that granule companies are virtually the only places that actually use true astragalus in Taiwan. Most large Taiwanese granule companies clearly differentiate and offer both products, and several U.S. suppliers of Taiwanese granules (such as KPC) give their customers a choice of either astragalus or hedysarum. That said, some of the smaller domestic granule producers in Taiwan often do not clearly state which form of Huang Qi is used.

Dr. Chang Yuan-Shiun (張永勳, pronounced Zhang Yong-Xun), a pharmacy expert and professor at China Medical University, recently collected samples of Huang Qi from 40 pharmacies throughout Taiwan. He reported that astragalus accounted for only three samples (7.5%), while hedysarum accounted for 37 samples (92.5%).

Hedysarum has a better taste and is thought to be superior for flavor. It is preferred for chicken soup and other dietary applications. However, the history and research base of astragalus is much more developed than that of hedysarum, so many clinical experts prefer to use astragalus.

Additionally, there are significant differences in the chemical profile of astragalus when it is grown in different provinces in China. In the case of astragalus, it is always best to check with your supplier to verify where the product came from. A good supplier should be able to tell you whether their product is derived from astragalus or hedysarum, and often they can even tell you which specific species and growing region it comes from.

Good quality astragalus should be deeply yellow. It can be pressed and sliced vertically (the most common method in the Hong Kong and U.S. markets), or it can be sliced horizontally or at an angle. Whole roots are even and cylindrical with a creamy brownish-yellow skin; they should be relatively thick but firm and dense. The outer surface should not be a deep black color (such roots have color that is artificially added). Wild roots are also available on the Chinese domestic market.

We only use the official sources of medicinals as specified in the Chinese Pharmacopoeia in our products. Therefore, our astragalus is always true Bei Qi (Huang Qi), hand-selected by our on-staff pharmacy experts.