Zanthoxylum nitidum
1、 Pharmacopoeia standard of Zanthoxylum nitidum         This product is the dried root of Zanthoxylum nitidum (roxb.) dc., a Rutaceae plant. It can be dug, washed, sliced or segmented all year round, and dried in the sun.
        [character]   This product is a thick piece or cylindrical short segment, 2-20cm long and 0.5-6 (10) cm thick. The surface is light brown yellow or light yellow, with bright yellow or yellowish brown round lenticel like spots. The section is smooth, the skin is light brown, the wood is light yellow, and concentric rings and dense holes can be seen. . It is slightly fragrant and tastes spicy and bitter.
        . A few calcium oxalate crystals and oil cells were scattered in phloem. The long diameter of oil cells was 52 ～ 122 μ m, and the short diameter was 28 ～ 87 μ M; There are lignified fibers on the outer edge of phloem, single or 2-5 groups. Xylem vessels are 35-98 μ m in diameter and surrounded by fiber bundles; The wood rays are 1-3 rows wide with single pits. Parenchyma cells were filled with starch granules.
        (2) Take 1g of this product powder, add 40ml of ethanol, sonicate for 1 hour, filter, evaporate the filtrate, add 1ml of ethanol to dissolve the residue, and use it as the test solution. Take another 1g of Zanthoxylum nitidum reference medicinal material and prepare the reference medicinal material solution by the same method. Then take the reference substance of nitidine chloride and add ethanol to make a solution containing 1mg per 1ml as the reference solution. Test according to thin-layer chromatography (general rule 0502), suck 2 μ l of each of the above three solutions, dot them on the same silica gel G thin-layer plate respectively, use chloroform methanol concentrated ammonia test solution (30:1:0.2) as the developing agent, develop, take out, dry, spray 10% sulfuric acid ethanol solution, heat at 105 ℃ until the spots are clear, and check under ultraviolet light (365nm). In the chromatogram of the test sample, fluorescent spots of the same color appear at the corresponding position of the chromatogram of the control medicinal material; On the position corresponding to the chromatogram of the reference substance, the same light yellow fluorescent spots appear.
        (3) Take ethoxychelerythrine reference substance and add ethanol to make a solution containing 1mg per 1ml as the reference solution. Test according to thin-layer chromatography (general rule 0502), suck 2 μ l each of the test solution, the reference medicinal material solution and the above reference solution under (2) of [identification], dot them on the same silica gel G thin-layer plate, use chloroform methanol (25:1) as the developing agent, develop, take out, air dry, and view under the ultraviolet light (365nm). In the chromatogram of the test sample, fluorescent spots of the same color appear at the corresponding position of the chromatogram of the control medicinal material; On the position corresponding to the chromatogram of the reference substance, the same light yellow fluorescent spots appear.
        [check]   Moisture   .
        Total ash   Not more than 7.0% (general rule 2302).
        ; Take the reference substance of zanthoxylin and add ethanol to make a solution containing 1mg per 1ml as the reference solution. Take 4ml of the test solution under [content determination] and concentrate it to 2ml as the test solution. Test according to thin-layer chromatography (general rule 0502), suck 2 μ l of each of the above two solutions, dot them on the same silica gel G thin-layer plate respectively, use petroleum ether (60 ~ 90 ℃) - chloroform methanol (2:13:1) as the developing agent, pre saturate for 20 minutes, develop, take out, dry, and view under ultraviolet light (365nm). In the chromatogram of the test sample, there should be no fluorescent spots of the same color at the position corresponding to the chromatogram of the control sample.
        ; According to the hot leaching method under the determination of alcohol soluble extract (general rule 2201), the use of ethanol as solvent shall not be less than 5.5%.
        [content determination]   Determine according to high-performance liquid chromatography (general rule 0512).
        ; Octadecylsilane bonded silica gel was used as filler; Gradient elution was performed with acetonitrile as mobile phase A and 0.1% formic acid triethylamine (pH4.5) as mobile phase B according to the following table; The detection wavelength is 273nm. The number of theoretical plates should not be less than 2500 based on the alkali peak of Zanthoxylum nitidum.
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        Time (min) mobile phase a (%) mobile phase B (%)
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     0～30       20→50     80→50  
    30～35       50→100    50→0  
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        Preparation of reference solution   Take an appropriate amount of nitidine chloride reference substance, accurately weigh it, add 70% methanol to make a solution containing 50 μ g per 1ml.
        Preparation of test solution   Take about 1g of this product powder (passing through No. 3 screen), weigh accurately, put it into a corked conical flask, add 20ml of 70% methanol, sonicate (power 200W, frequency 59khz) for 30 minutes, cool it, filter it, put the filtrate into a 50ml volumetric flask, add 20ml of 70% methanol to the filter residue and filter paper, sonicate for 30 minutes in the same way, cool it, filter it, put the filtrate into the same volumetric flask, add an appropriate amount of 70% methanol to wash twice, incorporate the washing solution into the same volumetric flask, add 70% methanol to the scale, shake it evenly, and then you can get it.
        ; Precisely suck 10 μ l of the reference solution and 10 μ l of the test solution respectively, inject them into the liquid chromatograph, and determine.
        According to the calculation of dry product, the content of nitidine chloride (c21h18o4 · CL) shall not be less than 0.13%.
        [nature, taste and meridian tropism]   Bitter, bitter, and flat; . Return to liver and stomach channels.
        ; Activating blood circulation and removing blood stasis, promoting qi and relieving pain, dispelling wind and unblocking collaterals, detoxifying and detumescence. ; External treatment of burns and scalds.
        [usage and dosage]   5 ～ 10g. For external use, apply appropriate amount, and apply it at the end of grinding or wash the affected part with boiling water.
        [note]   Do not overdose; Avoid taking with sour food.
        [storage] store in a dry place, damp proof and mothproof.


2、 Chemical constituents of Zanthoxylum nitidum
The root bark and stem bark contain alkaloids:Nitidine chloride（Nitidine Chloride），oxynitidine，dihydronitidine，hydroxynitidine，Colocasine（skimmianine），6-ethoxychelerythrine，Allocryptopine(α -allocryptopine), n-demethoxychelerythrine, et al. It also contains flavonoidsVitexin(Vitexin), Diosmin andcoumarin, amino acids, etc. Fresh leaves contain monoterpene volatile oils: limonene, furfuraldehyde.

3、 Pharmacological action of Zanthoxylum nitidum
; External treatment of burns and scalds.