文档介绍：大黄(Rhubarb)
Radix et Rhizoma Rhei
大黄 Dahuang (Rhubarb)
Radix et Rhizoma Rhei
Source
Plant Morphology
Habitat
Macroscopic Identification
Microscopic Identification
Constituents
Physicochemical Identification
Annotation
Questions
Reference Literatures
【Other Names】Jinwen、Chuanjun、Xining Rhubarb、
South Rhubarb、North Rhubarb、General。
【Record】First in the “Shen Nong's Herbal Classic”.
【Source】(Fam. Polygonaceae). the dried root and
rhizome of
① Rheum palmatum 掌叶大黄 as North Rhubarb
② Rheum tanguticum 唐古特大黄
③ Rheum officinale 药用大黄---- as South Rhubarb
大黄 Dahuang (Rhubarb)
Radix et Rhizoma Rhei
Common Characters of Polygonaceae:
① having ocreae (stipular sheath)
② simple-perianth flower
③ stamen 6-9
Respective Characters of the Plants in Rhubarb
Rheum palmatum: palmatifid leaf; flower, purple
掌状半裂叶
R. tanguticum: palmately parted leaf (partition);
flower, purple 掌状深裂
R. officinale: palmatilobate leaf; flower, yellow
掌状浅裂
【Plant Description】
Rheum officinale
palmatilobat leaf;
flower, yellow.
Rheum palmatum:
Gansu, Qinghai, Tibet, etc. mainly cultivated,
70~80% modity
Rheum tanguticum:
Qinghai, Gansu, Tibet. mainly wild,
5~10% modity
Rheum officinale:
Sichuan, Guizhou, Yunnan; wild and cultivated,
20~30% modity
【Habitat】
in late autumn when stem and
leaves are withered or in next
spring just before budding.
remove from rootlet and the
outer bark, cut into section , dry
directly.
【Collection and Preparation】
① subcylindrical, conical, hoof-shape, or irregular-shape. ② 3-10cm in diameter. ③ yellowish-brown to reddish-brown.④ texture, firm. ⑤ pith broad, with “star spots” arranged in ring or irregularly scattered. ⑥ odor, aroma; taste, bitter and slightly astringent; sticky and gritty on chewing.
【Macroscopic Identification】
掌叶大黄
Rheum palmatum