宋诗有云：“本草图经川续断，今人误作古兰看”。续断，其花如兰，其根入药，又名接骨草、小续断、川续断、鼓锤草等，分布于四川、湖广、云贵、西藏等省区，以四川所产品质最佳，习名川续断或川断。中药续断为川续断科川续断属多年生草本植物Dipsacus asper Wall. exHenry的干燥根，因能“续折接骨”而得名，临床用于补肾强骨、治疗跌打损伤、骨折等。
本期我们来一起认识续断这味神奇中药吧！
The classic illustration of Bencao depicts Chuan-Xu-Duan, but modern people mistakenly identify it as Gulan. Xu-Duan, with orchid-like flowers and medicinal roots, is also known as Ji- Gu-Cao, Xiao-Xu-Duan, Chuan-Xu-Duan, and Gu-Chui-Cao, among other vernacular names. It is distributed in provinces of Sichuan, Hubei, Hunan, Yunnan, Guizhou, and Tibet, with the Sichuan variety acclaimed for its superior quality and commonly known as Chuan-Xu-Duan or Chuan-Duan.
The traditional Chinese medicine Xu-Duan is the root of Dipsacus asper Wall. exHenry, a perennial herbaceous plant belonging to the Dipsacus family. Its dried roots earned the name due to their renowned ability to "mend and connect fractured bones." Clinically, Chuan-Xu-Duan is employed to tonify the kidneys and fortify bones, also served as a treatment for bruises, contusions, fractures, and other injuries. In this issue, let's explore the magical properties of Xu- Duan, the remarkable traditional Chinese medicine!
川续断的花（图左） 川续断的干燥根（图右）
1.性味归经与药典收录
续断源自《神农本草经》，位列上品。苦、辛，微温；归肝、肾经。
续断在历代本草及历版《中国药典》皆有收录。
Xu-Duan is originally documented and classified as a top-grade herb in the Chinese ancient book Shen Nong Ben Cao Jing. Xu-Duan has a bitter and pungent taste, with a slightly warm nature, and is attributed to the Liver and Kidney meridians, according to traditional Chinese medicines. Xu-Duan has been consistently documented and included in various historical materia medica books as well as successive editions of the Pharmacopoeia of the People's Republic of China.
2.续断的炮制
续断，秋季采挖，除去根头和须根，用微火烘至半干，堆置“发汗”至内部变绿色时，再烘干。
2020版《中国药典》收录续断的炮制方法有3种，分别为生续断、酒续断和盐续断。洗净，润透，切厚片，干燥而得续断片（生续断），其气微，味苦、微甜而涩；续断片经酒炙而得酒续断，其表面浅黑色或灰褐色，略有酒香气；续断片经盐炙可得盐续断，盐续断表面黑褐色，味微咸。
图为川续断种植基地
Xu-Duan is collected and harvested during autumn. After excavation, the root crown and root hairs are removed. It is then gently heated until partially dried, followed by a "sweating" process until the internal part turns green. Afterward, it is further dried.
Three methods for preparing Xu-Duan were included in the 2020 edition of the Pharmacopoeia of the People's Republic of China, which were raw Xu-Duan, wine-processed Xu- Duan, and salt-processed Xu-Duan. The raw Xu-Duan is prepared by thoroughly washing, moistening, cutting into thick slices, and then drying. It has a mild aroma, bitter taste, slight sweetness, and astringency.The wine-processed Xu-Duan is obtained by baking Xu-Duan with wine, resulting in a surface that is light black or grayish-brown with a faint wine aroma.The salt-processed Xu-Duan is obtained by baking Xu Duan with salt, resulting in a surface that is dark brown and a slightly salty taste.
3.续断及其炮制品的质量标准
《中国药典》（2020版）规定，以川续断皂苷Ⅵ作为续断的指标成分，用高效液相色谱法测定其含量。按干燥品计算，生续断中化合物川续断皂苷Ⅵ的含量不得少于2.0%，酒续断和盐续断中川续断皂苷Ⅵ的含量不得少于1.5%。
According to the Pharmacopoeia of the People's Republic of China (2020 edition), the content of compound dipsacus asperoside VI is specified as the indicator component for Xu-Duan, and its quantity is determined using high-performance liquid chromatography. Calculated on a dry basis, the content of dipsacus asperoside VI in raw Xu-Duan should not be less than 2.0%, while in wine-processed Xu-Duan and salt-processed Xu-Duan, the content of dipsacus-asperoside VI should not be less than 1.5%.
川续断皂苷VI的化学结构
4.续断的化学成分
续断的化学成分主要包括三萜皂苷、环烯醚萜苷、生物碱、酚酸等。
三萜皂苷类化合物是续断的主要活性成分，其结构类型以齐墩果烷型为主。迄今已从续断中鉴定的三萜类化合物主要包括川续断皂苷A、川续断皂苷B、川续断皂苷C、川续断皂苷Ⅵ、川续断皂苷Ⅴ、川续断皂苷X、川续断皂苷Ⅻ、刺楸皂苷A、日本续断皂苷E1、威岩仙皂苷A、灰毡毛忍冬皂苷A、灰毡毛忍冬皂苷B、HN saponin F等，其中川续断皂苷Ⅵ被作为续断的指标成分进行质量检测。
已从续断中鉴定的环烯醚萜类化合物包括马钱子苷、马钱苷酸、獐牙菜苷、茶茱萸苷、大花双参苷A、续断苷A、续断苷B、续断苷E、续断苷F、续断苷H、林生续断苷Ⅰ、林生续断苷Ⅲ、林生续断苷Ⅳ等；其生物碱类化合物主要为坎特莱因碱、喜树碱和龙胆碱；酚酸类化合物包括2,6-二羟基桂皮酸、香草酸、咖啡酸、咖啡奎宁酸、绿原酸、4-咖啡奎宁酸、5-咖啡奎宁酸等。
The chemical components of Xu-Duan mainly include triterpenoid saponins, iridoids, alkaloids, and phenolic acids. Triterpenoid saponins are the primary active constituents of Xu- Duan, and are mainly formed in quassinoid-type. Up to now, identified triterpenoids from Xu- Duan mainly include dipsacus asperoside A, dipsacus asperoside B, dipsacus asperoside C, dipsacus asperoside VI, dipsacus asperoside V, dipsacus asperoside X, dipsacus asperoside XII, kalopanaxsaponin A, Japondisaponin E1, cauloside A, macranthoidin A, macranthoside B, and HN saponin F. Among them, dipsacus asperoside VI is used as the indicator component for quality testing of Xu-Duan.
The identified iridoids from Xu-Duan include loganin, loganin acid, sweroside, cantleyoside, triptostoside A, Xu Duan glycoside A, Xu Duan glycoside B, Xu Duan glycoside E, Xu Duan glycoside F, Xu Duan glycoside H, sylvestroside I, sylvestroside III, sylvestroside IV, etc. The alkaloids found in Xu-Duan mainly consist of cantleyine, venoterpine, and gentianine. Additionally, the phenolic acid compounds include 2,6-dihydroxy-cinnamic acid, vanillic acid, caffeic acid, caffeoylquinic acid, chlorogenic acid, 4-caffeoylquinic acid, 5-caffeoylquinic acid, and others have been identified from Xu-Duan.
5.续断的药理活性及应用
续断传统功效有补肝肾、强筋骨、续折伤、止崩漏等，主要用于治疗肝肾不足、腰膝酸软、风湿痹痛、跌扑损伤、筋伤骨折、崩漏、胎漏等。其中，酒续断多用于风湿痹痛，跌扑损伤，筋伤骨折；而盐续断多用于腰膝酸软。现代药理学研究表明续断还具有抗菌、消炎、抗氧化、抗肿瘤、保护神经等药理活性。
The traditional medicinal properties of Xu-Duan include tonifying the Liver and Kidneys, strengthening muscles and bones, mending injuries, and stopping excessive uterine bleeding. It is primarily used to treat conditions such as Liver and Kidney insufficiency, lumbago and weak knees, rheumatism and arthralgia, contusions and injuries, muscular and bone fractures, and uterine or vaginal bleeding disorders. Wine-processed Xu-Duan is commonly employed for conditions like rheumatism and arthralgia, contusions and injuries, and muscular and bone fractures，while salt-processed Xu-Duan is frequently used for treating lumbago and weak knees. Additional, it has been revealed by modern pharmacological studies that Xu-Duan possesses antibacterial, anti-inflammatory, antioxidant, anti-tumor, and neuroprotective effects.
The clinical application of Xu-Duan commonly involves raw Xu-Duan. For instance, in formulations Zhuang-Yao-Jian-Shen-Wan, Xu-Duan is combined with other TCM such as deer antler, Cistanche, and Dodder seed to disperse cold, reinforce yang, promote blood circulation, and tonify the kidneys. In Shu-Jin-Xiao-Tong-Jiao-Nang, Xu-Duan is utilized for its properties in promoting blood circulation, resolving stasis, alleviating pain, and reducing swelling, which make it an effective medicine for treating contusions and injuries, as well as rheumatic arthralgia.
