Yunxi Huangjiang

Yunxi Huangjiang

Yunxi Huangjiang is an agricultural product with a geographical indication.

　　Huangjiang, also known as Dioscorea zingiberensis C. H. Wright, is a monocotyledonous plant of the Dioscoreaceae family, Dioscorea genus, and is endemic to China. There are about 850 species of Dioscorea worldwide, with around 30 species accounting for over 1% of the world's saponin content. China has approximately 50 species, among which 17 species, 1 subspecies, and 2 varieties contain saponins, making up over 50% of the world’s saponin-containing plants, with a content as high as 16.15%. This exceeds the 15% record of Dioscorea composita from Mexico, making it the top variety in the world. Huangjiang is an ideal raw material for extracting steroidal hormone medications. Saponins (commonly known as diosgenin), when their steroidal structure compounds are modified, can yield various steroidal hormone drugs. The initial products extracted from Huangjiang rhizomes include diosgenone, progesterone acetate (monoester), prednisone, cortisone series, as well as intermediates or drugs such as oxytocin and contraceptives — numbering in the thousands. Although China started later, it can still synthesize nearly 100 types of products. In short, using Huangjiang as a raw material, it is possible to synthesize and convert into a range of essential products such as sex hormones, anabolic hormones, and corticosteroid hormones that are critical for national livelihoods. For this reason, the pharmaceutical industry calls it “medicinal gold.” In addition to domestic demand, it has been in high demand in over 120 countries and regions including the United States, Germany, France, and Japan. Furthermore, Huangjiang contains not only saponins but also 45–50% starch, which can be used in the brewing industry to produce alcohol, yeast powder, inosine powder, glucose, etc. Its 40–50% cellulose content can be used to produce carboxymethyl cellulose. The waste liquid from diosgenin extraction can yield agricultural nucleic acids, which serve as high-quality fertilizer. The rhizomes also have a wide range of applications in the pharmaceutical, food, high-end cosmetics, and veterinary medicine industries. For instance, when used directly as medicine, the rhizomes have the effects of removing dampness and clearing heat and toxins, and are used in folk medicine to treat acute suppurative skin infections, soft tissue injuries, bee stings, insect bites, and various surgical inflammations, as well as to strengthen bones and physique. Water-soluble active substances can be used to produce diosbulbin, which treats coronary heart disease effectively with minimal side effects.

　　Diovan XinXueKang, developed by the Chengdu Institute of Biology, helps regulate metabolism, treats arteriosclerosis, and has good therapeutic effects on cardiovascular diseases, selling well in both domestic and international markets. Additionally, research by the Wuhan Institute of Botany at the Chinese Academy of Sciences found that active substances in Huangjiang are ideal for killing snails and preventing schistosomiasis. Not only are they highly effective in snail eradication, but they also do not pollute the environment, helping maintain ecological balance.

　　As a uniquely domestic steroidal medicinal plant, Huangjiang historically formed vast wild resource zones. The Qing Dynasty Tongzhi County Annals recorded: “The county produces Huangjiang, commonly known as ‘firehead root.’” The rhizomes were used directly as medicine, with effects such as removing dampness, clearing heat and toxins, and treating acute suppurative skin infections, soft tissue injuries, bee stings, insect bites, and various surgical inflammations, while also strengthening bones and physique. During famine years, it was often used as food by disaster victims. In the early years after liberation, it was an important export commodity, with annual exports ranging from tens of thousands to hundreds of thousands of jin of ginger slices. Ding Zhizun from the Nanjing Botanical Institute, in his book “Steroidal Medicinal Plants,” concluded through a nationwide resource survey that Huangjiang from the Qinba Mountain area is of the highest quality.

　　With the depletion of wild resources and the successful domestication of Huangjiang (“wild to cultivated”), the cultivation area of Huangjiang in Yunxi County has continued to expand, gradually forming today’s industrialized pattern of “company + farmer + base + association + market.” The annual output reaches 100,000–150,000 tons of Huangjiang and 600–900 tons of diosgenin, with an output value of over 500 million yuan, providing nearly 50 million yuan in fiscal revenue and increasing per capita income by 700 yuan. It is truly a pillar industry. In April 2000, the Ministry of Agriculture awarded Yunxi County the title of “Hometown of Chinese Huangjiang.”

　　Geographical Scope

　　The production area of Yunxi Huangjiang covers 18 townships (towns) under the jurisdiction of Yunxi County, Hubei Province, including Chengguan Town, Tumen Town, Xiangkou Township, Shangjin Town, Dianzi Town, Guanfang Township, Hubeikou Hui Autonomous Township, Jingyang Township, Jiahe Town, Yangwei Town, Jianchi Township, Guanyin Town, Ma’an Town, Liulang Township, Hejia Town, Anjia Township, Sanguandong Forest Area, and Huaihuang Forest Special Farm. Its geographic location is between 109°16′–110°42′ east longitude and 32°54′–33°16′ north latitude. The total area is 12,000 hectares, with an average annual output of 135,000 tons and an annual output value of 405 million yuan.