Northern Ban Lan Gen (Clumpy/Knobby)

Northern Ban Lan Gen (Cylindrical, twisted, grayish-yellow, with longitudinal wrinkles and dense lenticels)

Northern Ban Lan Gen Slice

Northern Ban Lan Gen Slice

Southern Ban Lan Gen (Mostly thin, long, and curved roots)

Southern Ban Lan Gen Slice

Ban Lan Gen Slice

Ban Lan Gen Slice

【Naming】

Ban Lan Gen

【Source】

Ben Jing (Shen Nong’s Classic of Materia Medica)

【Common Usage Level】

C

【Botanical Origin】

In the north, this product commonly uses the dried roots of Isatis tinctoria L. and Isatis indigotica Fort. from the Brassicaceae family. In the south, it uses the dried rhizomes with roots of Strobilanthes flaccidifolius Nees from the Acanthaceae family.

【Characteristics】

1. Northern Ban Lan Gen (Isatis tinctoria): The root is cylindrical, slightly curved, about 8~16㎝ long, and 3~8㎜ in diameter; the surface is brownish-yellow, the root head is slightly enlarged, with stem scars and leaf bases at the top. The densely arranged warty protrusions of the petiole remnants at the top are characteristic of this product. It has longitudinal wrinkles and transverse lenticels. A few still have lateral roots, but most have been removed. It is brittle and easily broken.

Isatis tinctoria and Isatis indigotica (菘青) are basically similar in shape. The difference is that the former has thinner roots, many green or dark green petiole remnants at the root head, a flatter cross-section, and a slightly sweet taste; while the latter has thicker roots, many warty protrusions at the root head, a slightly fibrous cross-section, and a bland taste.

Processed slices: Oblique slices, 2~4㎝ long and about 3㎜ thick. The slices are off-white with a yellow wood core, resembling a chrysanthemum heart. There is a brown ring in the middle layer. It has no odor and tastes slightly sweet, then bitter and astringent.

2. Southern Ban Lan Gen (Strobilanthes flaccidifolius): The total length is 15~20㎝. The rhizome is cylindrical, with many branches, slightly enlarged nodes, and rhizomes branching out from the nodes. There are many thin and curved roots, 1~2㎜ in diameter, with a brown outer surface. The rhizome is solid and brittle, easily broken, and the cross-section has a large pith. The shape is very different from the above two types and is very easy to distinguish.

【Identification】

Northern Ban Lan Gen is considered good if it is dry, long, plump, white, has sufficient powder content, and is free of impurities. Southern Ban Lan Gen is considered good if it has many roots, is bluish-brown in color, and has few stems and branches.

【Identification Terminology】

1. Clump/Knobby (疙瘩/粒結仔): (1) Refers to the swollen part of the root head of root-type medicinal materials. Such as the root head of Ban Lan Gen, Sophora tonkinensis root, and Ku Shen. (2) Refers to the shortened rhizome (irregularly shaped mass) of root and rhizome medicinal materials, such as the rhizome part of Long Dan, Bai Wei, Zi Wan, Xu Chang Qing, Yuan Hua, Bai Qian, and Wei Ling Xian.

【Category】

Roots