aloe
1、 Aloe pharmacopoeia standard       This product is concentrated and dried juice from the leaves of Liliaceae aloe barbadmsis Miller, Cape Aloe ferox Miller or other related plants of the same genus. The former is known as "old aloe" and the latter is known as "new aloe".
      [character]   Aloe Vera is irregular massive, often broken into polygonal shapes, with different sizes. . It is light, hard, not easy to break, with rough section or hemp grain. Rich in moisture absorption. It has a special odor and tastes very bitter.
      The surface of Cape aloe is dark brown, slightly green and shiny. It is light, loose, fragile, and has a glassy section with laminations.
      [identification] (1) take 0.5g of this product powder, add 50ml of water, shake, filter, take 5ml of filtrate, add 0.2g of borax, heat to dissolve, take a few drops of solution, add 30ml of water, shake well, show green fluorescence, observe under UV light (365nm), show yellow fluorescence; Take 2ml of the filtrate, add 2ml of nitric acid, shake well, and the aloe vera shows brownish red, and the aloe vera of the Cape of good hope shows yellowish green; Take another 2ml of filtrate and add an equal amount of saturated bromine water to form a yellow precipitate.
      (2) Take 0.5g of this product powder, add 20ml of methanol, heat it on a water bath to boil, shake it for several minutes, filter it, and use the filtrate as the test solution. In addition, take aloin reference substance and add methanol to make a solution containing 5mg per 1ml as the reference solution. Test according to thin-layer chromatography (general rule 0502), suck 5 μ l of each of the above two solutions, dot them on the same silica gel G thin-layer plate, use ethyl acetate methanol water (100:17:13) as the developing agent, develop, take out, dry, spray 10% potassium hydroxide methanol solution, and inspect under the ultraviolet light (365nm). In the chromatogram of the test sample, fluorescent spots of the same color appear at the corresponding positions of the chromatogram of the control sample.
      [check]   Moisture   .
      The total ash content shall not exceed 4.0% (general rule 2302).
      [content determination]   Determine according to high-performance liquid chromatography (general rule 0512).
      Chromatographic conditions and system suitability test   Octadecylsilane bonded silica gel was used as filler; Acetonitrile water (25:75) was used as mobile phase; The detection wavelength is 355nm. The number of theoretical plates should not be less than 2000 according to the peak of aloin.
      Preparation of reference solution   Take an appropriate amount of aloin reference substance, weigh accurately, add methanol to make a solution containing 0.2mg per 1ml.
      Preparation of test solution   Take about 0.1g (or about 0.2g of Cape of good hope aloe powder) of kulazu aloe powder (passing through No. 5 screen), weigh it accurately, put it into a 100ml measuring flask, add appropriate amount of methanol, sonicate (power 250W, frequency 33khz) for 30 minutes, cool it, add methanol to dilute to the scale, 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.
      According to the dry product, the content of Aloe Vera glycoside (c21h22o9) and Aloe Vera Vera should not be less than 16.0% and 6.0% respectively.
      Decoction pieces
      ; Smash into small pieces.
      [identification] [inspection] [content determination]   Same as medicinal materials.
      [nature, taste and meridian tropism]   Bitter, cold. It belongs to the liver, stomach and large intestine.
      ; Diarrhea and defecation, clearing liver and fire, killing insects and curing malnutrition. ; External treatment of ringworm and sore.
      [usage and dosage]   2～5g， Yi Ru Wan San. For external use, apply appropriate amount to the affected area after grinding.
      [note]   Caution for pregnant women.
      [storage]   Store in a cool and dry place.


2、 Chemical constituents of Aloe Vera
1. aloe vera leaves contain anthracene compounds:Aloin（barbaloin），Aloin a（aloinA），21.78%，Aloin B（aloinB）， . It also contains about 12% resin, which is composed of aloeresitanol andcinnamic acid(cinnamic acid) combined esters. L-asparagine（L-asparagine），L-aspartic acid （L-aspqrtic acid），L-threonine（L-threonine），L-tryptophan(l-tryp0tophane) and other amino acids; Cholesterol,Campesterol（campesterol），β - sitosterol（β-sitosterol），Lupeol（lupeol）； Malic acid,Citric acid anhydrous（citric acid）， Organic acids such as tartaric Aicd and inorganic elements such as sodium, potassium, calcium, magnesium and chlorine. It also contains D-glucose and D-mannose. In addition, it contains polysaccharide mixture. The base mainly contains pectin acid and d-galactan. The molar ratio of glucomannan is 5:1; In d-galactan, galactose accounted for 92.9% and galacturonic acid accounted for 3.8%; The molar ratio of glucose to mannose in grape mannan is 1:22. ; It also contains a polysaccharide, the molar ratio of D-glucose, D-mannose and D-galactose in the base is 2:2:1, and a small amount of arabinosr and rhamnose.
2. aloe vera leaves contain aloesin,Aloe Vera a（aloenin A）， Lauric acid,Myristic acid（myristic acid） ，palmitic acid（palmitic acid）， Stearic acid, palmitoleic acid, hexadecadienoic acid, oleic acid, linoleic acid, linolenic acid, gluconic acid,Beta carotene（beta-carotene）， Vitamin B1, B2, C, D, e, PP, and three polysaccharides coded as A60, a90a, and a90b with relative molecular weights of 12000, 47000, and 12000, respectively. A60 is mannan, and a90b is grape mannan, in which the molar ratio of glucose to mannose is 3:4. It also contains aloe polysaccharide.
3. Cape of good hope aloe leaf containsAloin，Aloin BIt also contains aloeresin a, B, CAloinDAmong them, aloe resin B is aloe glycine. It also contains isoaloeresin a, aloe pine, feroxidin, feroxin A and B, furoaloesone, feralolide, 5-hydroxy aloe emodin a.

3、 Pharmacological action of Aloe
① Purgative action
; These anthracene containing glycosomes need to release emodin in the intestinal tract to play a stimulatory purgative role. Among all rhubarb glycosides laxatives, aloe is the most irritating. Its effect is accompanied by significant abdominal pain and pelvic congestion, which can cause nephritis in severe cases. Due to the different amount of active ingredients in various aloes, it was suggested to use pure aloe emodin instead of aloe as a laxative. Oral administration of Aloe Vera to dogs (2-5g) and cats (0.2-1.0g) can cause diarrhea; It has no effect on promoting peristalsis of isolated small intestine; The main site of its diarrhea is the large intestine. The suspension (400 mg / ml) of Aloe Vera produced in Yunnan, China, was given to male rats by gavage, and its diarrhea effect was similar to that of imported aloe vera. .
② Treating trauma
Aloe Vera water extract (10% solution) has been used in rabbits with artificial conjunctival edema, which can shorten the cure days; . In recent years, aloe leaf pulp juice has been used to make gel preparations containing polysaccharides (polymers) for skin or other tissue trauma and burns, and even some people think it may be used for anti Pseudomonas aeruginosa. Tissue culture method has proved that this aloe gel has low toxicity. Aloe extract as oil cream has mild protective effect on mice exposed to local X-ray.
③ Anticancer effect
Aloe extract 1:500 alcohol extract can inhibit the growth of sarcoma-180 and Ehrlich ascites cancer in vivo; An almost pure substance isolated from the extract has higher anticancer effect, and its median lethal dose in mice is 5g / kg.
④ Other roles
Aloe extract 1:500 has inhibitory effect on isolated toad heart, and its white powder 1:100 solution also has inhibitory effect. The aqueous solution of aloe concentrated extract can resist the toxicity of chloral hydrate to isolated toad heart; Lower limb vascular perfusion, 1:200 for contraction, 1:1000 for mild expansion; It has antidiuretic effect in toads, but it has no effect on urine output in rabbits when 1% aqueous extract is injected intravenously at 1ml / kg. . It can shorten the coagulation time. When 15 ml aloe extract was given to dogs with artificial gastric fistula every day, the gastric juice secretion increased slightly after 20 days, but stopped after a few days and returned to normal. The extract has some excitatory effects on adrenal cortex and can reduce the content of vitamin C in rat adrenal gland. Aloe Vera and its aqueous extract are widely used in tissue therapy in the Soviet Union. Aloe water extract (1:2) has different degrees of inhibition on dermatophytes such as tinea inguinal epidermidis, tinea rubrum, and Nocardia starum in test tubes. Its alcohol extract also had some inhibitory effects on human tuberculosis in vitro (1:3000 ～ 300).