Dioscorea Rhizome (Bi Xie)
Dioscorea Rhizome (Bi Xie)(Smilax china L.)
Dioscorea Rhizome (Bi Xie) slices
Sichuan Dioscorea Rhizome (Bi Xie)(Yellowish-white bark, color ring spots, loose texture and slightly elastic)
White Dioscorea Rhizome (Bi Xie)(Cottony texture, light and fluffy, slightly firm and brittle, elastic)
White Dioscorea Rhizome (Bi Xie)(Top) Sichuan Dioscorea Rhizome (Bi Xie)(Bottom)
Dioscorea Rhizome (Bi Xie)(Top) Fu Ling (Poria)(Bottom)
Fu Ling (Poria)(Top) Dioscorea Rhizome (Bi Xie)(Bottom)
【Name】
【Source】
Classified as a medium-grade herb in the *Shen Nong Ben Cao Jing*
【Frequency of Use】
C (Common)
【Botanical Origin】
The rhizome of various *Dioscorea* spp. plants from the Dioscoreaceae family. “Fen Bi Xie” (Powdered Dioscorea Rhizome) is the rhizome of *Dioscorea collettii* Hook. f. var. *hypoglauca*（Palibin）Pei et Ting（D. *hypoglauca* Palibin）. “Mian Bi Xie” (Cottony Dioscorea Rhizome) is the rhizome of *Dioscorea septemloba* Thunb. or *Dioscorea futschauensis* Uline ex R. Kunth. “Shan Bi Xie” is the rhizome of *Dioscorea tokoro* Makino.
【Characteristics】
This product is an oval tuber. Commercial *Bi Xie* is often a thick cross-sectional slice of the rhizome.
(1) Sichuan *Bi Xie*: Irregular in shape, approximately 2-5mm thick. The edge is brownish-yellow, and root scars may sometimes be visible. The cut surface is yellowish-white. A brownish endodermis ring can be seen near the edge. The cortex is external to the ring, and the stele is internal, with scattered dot-like vascular bundles.
(2) Fen Bi Xie (Powdered Dioscorea Rhizome): Mostly irregular slices, uneven edges, some with brownish-black outer skin, about 1-3mm thick, brown edges, slightly curled, sometimes visible root scars. The cut surface is delicate and flat, yellowish-white, with yellow veined patterns. The brown ring is not very obvious. The vascular bundles of the stele are vaguely visible. The cut surface is rough and spongy. Veins are obvious when viewed against the light. This material is tough, powdery, has a slight odor, and tastes slightly sweet.
(3) Mian Bi Xie (Cottony Dioscorea Rhizome): Mostly slices, light yellowish-white, with vein points, yellow-brown skin on the edges, often curled around the periphery, loose and soft in texture, like cotton wool, slightly bitter in taste. *Dioscorea futschauensis* is also often cut into thin slices, yellowish-white to grayish-white, powdery, with scattered dot-like vascular bundles, slightly bitter and pungent in taste.
(4) Bai Bi Xie (White Dioscorea Rhizome): The commercial product is an irregular flake-shaped processed piece, about 2-4mm thick, rough edges, yellowish-white or light reddish-brown cut surface, firm and tough texture, containing yellow fibers, not easy to break.
【Identification】
*Zheng Lei Ben Cao*: “The softer inside is better.” *Ben Cao Gang Mu*: “[Gong said] Those without thorns have weak and soft roots, and the softer ones are better.” *Ren Shu Bian Lan*: “Sichuan *Bi Xie* is the best, the purple, thick and fragrant ones are better.” *Yao Xing Ge Kuo Si Bai Wei*: “*Bi Xie*, the white ones are the best.” *Ben Cao Bei Yao*: “There are yellow and white types, the yellow ones are long and whip-like, the white ones are empty and soft, the soft ones are good.” *Ben Jing Feng Yuan*: “The ones with left-handed patterns are good.” *Ben Cao Qiu Zhen*: “The white, empty, and soft ones are good.” *Yan Fang Xin Bian*: “*Bi Xie*, the ones with red dots are good.”
It is best to have dry, white, uniformly thick slices, without insect damage.
【Chapter】
Rhizomes