Pharmaceutical Material Identification:
Morphological identification: The root is spherical or irregularly shaped with a diameter of 10-40cm. The surface is brown or dark brown with irregular cracks and numerous small protrusions. The commercial product is usually cross-sectioned or longitudinally sliced, with a thickness of 0.5-1cm. The fresh cut surface is pale yellow to yellow, or turns darker when stored. The cross-section often shows a circular arrangement of vascular bundles (triple vascular bundles) in concentric circles, with slight point-like protrusions when dried. It has a faint odor and a bitter taste.
Physicochemical identification:
(1) Take 1g of the crude powder, add 10ml of ethanol, cold soak overnight, and filter. Evaporate the filtrate to dryness, and dissolve the residue in 4ml of dilute hydrochloric acid, then filter. Take 1ml of the filtrate, add 2 drops of modified bismuth potassium iodide test solution, which produces a large amount of orange precipitate; take another 1ml of the filtrate, add 2 drops of mercuric potassium iodide test solution, which produces a large amount of yellowish-white precipitate. (Check for alkaloids) (2) Place the fresh cut surface of the herb under a UV lamp (254nm) and observe bright sky blue fluorescence.
Microscopic identification of cross-section of the root:
The cortex occasionally contains scattered stone cells, elliptical in shape, with a wall thickness of 4-8μm. The thin-walled cells of this material contain more rod crystals, measuring 4-14 (-28)μm in length, and a few short rod crystals, sand crystals, and square crystals. The starch grains are single, round, with a diameter of 5-17 (-21)μm and a distinct hilum. Occasionally, compound grains consisting of 2-3 granules are present.
Introduction to pictures of Rulan:
Rulan
Fruit of Rulan
Leaf of Rulan
Root of Rulan
