Senna leaf
1、 Pharmacopoeia standard of senna leaf       This product is the dried leaflet of the legume Cassia angustifolia Vahl or Cassia acutifolia delile.
      [character] Senna angustifolia   It is long ovate or ovate lanceolate, 1.5-5cm long and 0.4-2cm wide. The leaf ends are acute, and the leaf base is slightly asymmetric. It is entire. The upper surface is yellowish green, the lower surface is light yellowish green, hairless or nearly hairless, and the leaf veins are slightly raised. Leathery. .
      ; It is lanceolate or long ovate, slightly curly, with short pointed or slightly protruding leaf ends, asymmetric leaf base, and fine and short hairy antlers on both sides.
      [identification] (1) the powder of this product is light green or yellowish green. There are many crystal fibers, and the diameter of calcium oxalate square crystal is 12 ～ 15 μ M. Non glandular hairs are single-cell, 100-350 μ m long, 12-25 μ m in diameter, with thick walls and warty protrusions. Calcium oxalate clusters were found in mesophyll parenchyma cells, with a diameter of 9-20 μ M.The diameter of calcium oxalate clusters was 0.5-0.5 μ M.The diameter of calcium oxalate clusters was 0.5-0.5 μ M.The diameter of calcium oxalate clusters was. The surface of the upper and lower epidermal cells was polygonal, and the vertical walls were flat and straight; The upper and lower epidermis have stomata, mainly horizontal axis type, and most of the accessory guard cells are 2 or 3.
      (2) Take 25mg of this product powder, add 50ml of water and 2ml of hydrochloric acid, heat it in a water bath for 15 minutes, cool it, add 40ml of ether, shake it for extraction, separate the ether layer, dehydrate it through an anhydrous sodium sulfate layer, filter it, take 5ml of filtrate, evaporate it to dryness, cool it, add 5ml of ammonia test solution, the solution turns yellow or orange, and turn purple red after heating it in a water bath for 2 minutes.
      (3) Take 1g of the product powder, add 10ml of dilute ethanol, sonicate for 30 minutes, centrifuge, take the supernatant, evaporate to dryness, add 10ml of water to dissolve the residue, shake and extract three times with petroleum ether (60 ～ 90 ℃), 15ml each time, discard the petroleum ether solution, evaporate the water solution, add 5ml of dilute ethanol to dissolve the residue, and use it as the test solution. Another 1g of senna leaf control medicinal material was prepared into the control medicinal material solution by the same method. According to the test of thin-layer chromatography (general rule 0502), suck 3 μ l of each of the above two solutions, dot them on the same silica gel G thin-layer plate respectively, make them into strips, use ethyl acetate-n-propanol-water (4:4:3) as the developing agent, pre equilibrate the developing cylinder for 15 minutes, develop, take out, dry, and view under the UV 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; Spray 20% nitric acid solution, heat it at 120 ℃ for about 10 minutes, cool it, and then spray 5% potassium hydroxide in dilute ethanol solution. In the chromatogram of the test sample, spots of the same color appear at the corresponding position of the chromatogram of the control medicinal material.
      ; Not more than 6% (general rule 2301).
      Moisture   .
      [content determination] determine according to HPLC (general rule 0512).
      ; Octadecylsilane bonded silica gel was used as filler; A 1000ml mixed solution of acetonitrile-5mmol/l tetraheptylammonium bromide in acetic acid sodium acetate buffer (pH5.0) (1 → 10) [note] (35:65) was added, and 2.45G tetraheptylammonium bromide was used as the mobile phase; The detection wavelength was 340nm, and the column temperature was 40 ℃. The number of theoretical plates shall not be less than 6500 according to the peak of sennoside B.
      Preparation of reference solution   Take an appropriate amount of sennoside A and sennoside B reference substances, dry them under reduced pressure for 12 hours, put them into a brown volumetric flask, add 0.1% sodium bicarbonate solution to make a mixed solution containing A50 μ g and b0.1mg sennoside per 1ml, and shake them well.
      Preparation of test solution   Take about 0.5g of the fine powder of this product, accurately weigh it, place it in a corked conical flask, precisely add 50ml of 0.1% sodium bicarbonate solution, weigh it, sonicate for 15 minutes (30 ~ 40 ℃), cool it, weigh it again, make up the lost weight with 0.1% sodium bicarbonate solution, shake it well, filter it, and take the filtrate.
      Assay   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.
      The total amount of sennoside a (c42h38o20) and sennoside B (c42h38o20) in this product shall not be less than 1.1% according to the dry product.
      [nature, taste and meridian tropism] sweet, bitter and cold. Return to the large intestine meridian.
      [functions and indications] it can relieve heat and stagnation, relieve constipation and promote diuresis. For heat accumulation, constipation, abdominal pain, edema and fullness.
      [usage and dosage] 2 ～ 6G, after taking, or taking it in boiling water.
      [note] pregnant women should use it with caution.
      [storage] keep away from light and in a ventilated and dry place.
      Note: preparation of 1mol/l acetic acid sodium acetate (pH5.0) buffer   Take 1mol/l sodium acetate solution, use dilute acetic acid test solution to prepare a solution with pH of 5.0, and then dilute it 10 times.


2、 Chemical constituents of senna leaf
Narrow leaf Senna containssennoside a （sennoside）、SennosideB、SennosideC、SennosideD，Chrysophanol（crysophanol），Emodin（emodin），Emodin methyl ether（physcion）， 3-methyl-8-shenoxy-2-acetyl-1,6-naphthodiphenol-6-o - β - D-glucoside, the leaflet containsKaempferol（kaempferol)。 Senna acuminata containssennoside a 、Sennoside B 、Sennoside C 、Sennoside D ，Emodin，Emodin methyl ether，Chrysophanol. the tender leaves containKaempferolIn addition, the leaves of the same genus Cassia auriculata contain leucoanthocyanins, and the bark contains polyphenoloxidase.

3、 Pharmacological action of senna leaf
1. purgative effect this product has a significant purgative effect on mice, rats, rabbits and other animals and people. Mice and rabbits cause diarrhea 2-4b after administration, and humans cause diarrhea about 6h after oral administration. The effective components of this product for diarrhea are mainly sennoside A and B, especially sennoside A. although sennoside C has similar diarrhea inducing effect as a, its content is very small. Sennoside a20mg/kg can cause diarrhea in mice. However, if 20% C is mixed into a, the effect of sennoside a can be enhanced by 1.6 times. Sennoside can be partially absorbed in the small intestine, and then enter the large intestine through blood flow or bile, while it mainly enters the large intestine directly from the small intestine. Under the action of bacteria in the intestine, it is hydrolyzed and reduced to anthrone rhein or anthrone rhein-8-glucoside. . On the other hand, in flipping the small intestine and colon sac, sennoside can prevent the trans intestinal wall transport of glucose and Na, indicating that inhibiting the intestinal absorption of glucose, sodium and water, increasing the intestinal lumen content and then stimulating the intestinal wall to reflexively enhance the peristalsis of the small intestine and colon, may also be one of its diarrhea mechanisms, and the small intestine is also the action site of its diarrhea components.
. Spray the water extract of this product under the gastroscope on the bleeding site of the stomach. It can be seen directly that it has an immediate hemostatic effect. Intraperitoneal injection of senna saponins 200mg/kg could significantly shorten the bleeding time of mice. Senna leaf can increase the number of platelets and fibrinogen content, and shorten the coagulation time, thromboplastin time, plasma recalcification time and clot contraction time. In addition, the protective effect of this product on gastric mucosal injury induced by hydrochloric acid and indomethacin in rats is also conducive to the prevention and treatment of gastric and duodenal hemorrhage.
3. antibacterial effect senna leaf extract has inhibitory effect on a variety of bacteria, such as Escherichia coli, proteus, Shigella, Streptococcus A, white beads and some pathogenic skin fungi.
4. other effects for experimental intestinal infarction Yin rats, sennoside 50mg/kg intraperitoneal injection can restore the reduced histamine content of intestinal mucosa to the normal level. In addition, it has been reported that this product has a curare like effect, which can block the transmission of impulse at the nerve muscle junction, prevent the binding of acetylcholine and M receptor, and make the muscle relax.
5. the LD50 of toxic Senna glycosides injected intraperitoneally into mice is 1.414g/kg, equivalent to 36.3g/kg of crude drugs.