Dendrobium
1、 Pharmacopoeia standard of Dendrobium officinale       ; Chrysotoxum lindl. or dendrobium  Fresh or dried stems of the cultivated species of fimbriatum hook. and similar species of the same genus. It can be harvested all year round, and the fresh user can remove the roots and sediment; After harvesting, the dry user removes impurities, scalds or softens them with boiling water, and then rubs them while drying them until the leaf sheaths are rubbed and dried.
      [character] fresh Dendrobium   It is cylindrical or oblate, about 30cm long and 0.4 ～ 1.2cm in diameter. Its surface is yellowish green, smooth or with longitudinal lines, and its nodes are obvious and dark, and there are membranous leaf sheaths on the nodes. The meat is juicy and easy to break. The breath is slight, the taste is slightly bitter and sweet, and the chewing is sticky.
      Dendrobium nobile   It is oblate cylindrical, 20 ～ 40cm long, 0.4 ～ 0.6cm in diameter, and 2.5 ～ 3cm long. The surface is golden yellow or yellow with green color, and there are deep longitudinal grooves. It is hard and brittle, and the section is flat and loose. The breath is slight and the taste is bitter.
      Dendrobium drumstick   It is in the shape of a woolen hammer, with a diameter of 1 ～ 3cm in the middle and 3 ～ 7 knots. The surface is smooth, golden yellow, with obvious raised edges. It is light and crunchy with spongy section. .
      Dendrobium fimbriae et al; It is long cylindrical, 20 ～ 150cm long, 0.4 ～ 1.2cm in diameter, with obvious nodes and 2 ～ 6cm long internodes. The surface is yellow to dark yellow, with deep longitudinal grooves. The texture is loose, and the section is flat or fibrous. The taste is light or slightly bitter, and the chewing is sticky.
      [identification] (1) cross section of this product: 1 column of epidermal cells of Dendrobium nobile, flat, covered with bright yellow cuticle. The size of basic tissue cells is quite different, with mural pores, scattered in most outer tough vascular bundles, arranged in 7-8 circles. The outer fiber bundle of the vascular bundle is crescent shaped or semicircular, and some of its outer parenchyma cells contain quasi circular siliceous blocks. There are 1-3 vessels with larger diameters in the xylem. Calcium oxalate containing needle crystal cells were mostly found near vascular bundles.
      Dendrobium drumstick   The epidermal cells were flat, the outer and lateral walls were thickened, and the cell cavity was narrow and long; . The cell size of basic tissues was significantly different. Most of the outer tough vascular bundles are slightly arranged in 10-12 circles. Xylem vessels are similar in size. In some cases, needle crystal bundle cells containing calcium oxalate can be seen.
      Epidermal cells such as Dendrobium fimbriae are oblate or square like, with thickened or non thickened walls. The basic tissue cells are similar or different in size, and most of the outer tough vascular bundles are scattered in a few circles. ; The medial fiber bundles are absent or present, and some of the medial and lateral fiber bundles are connected into sheaths. Some parenchymal cells contain calcium oxalate needle crystal bundles and starch granules.
      Powder grayish green or grayish yellow. Cuticular debris yellow; The surface of epidermal cells was long polygonal or polygonal like, and the vertical wall was beaded thickened. The bundle sheath fibers are in bundles or discrete, long fusiform or slender, with thick walls and few pits, surrounded by small cells containing siliceous blocks arranged in longitudinal rows. The wood fiber is slender, the end is pointed or blunt, and the wall is slightly thick. The diameter of reticulated duct, ladder shaped duct or marginal pit duct is 12-50 μ M. .
      (2) Dendrobium nobile   Take 1g of powder of the product (fresh product is crushed after drying), add 10ml of methanol, sonicate for 30 minutes, filter, and the filtrate is used as the test solution. In addition, take dendrobine reference substance and add methanol to make a solution containing 1mg per 1ml as the reference solution. According to the test of thin-layer chromatography (general rule 0502), suck 20 μ l of the test solution and 5 μ l of the control solution, respectively dot them on the same silica gel G thin-layer plate, develop them with petroleum ether (60 ～ 90 ℃) - acetone (7:3), take them out, dry them, and spray bismuth potassium iodide test solution. In the chromatogram of the test sample, spots with the same color appear at the corresponding position of the chromatogram of the control sample.
      Dendrobium drumstick   Take 25ml of the secondary filtrate from Dendrobium drumstick [content determination], evaporate it to dryness, add 5ml of methanol to dissolve the residue, and use it as the test solution. In addition, take the reference substance of maolanin and add methanol to make a solution containing 0.2mg per 1ml as the reference solution. According to the test of thin layer chromatography (general rule 0502), suck 5 ～ 10 μ l of the test solution and 5 μ l of the control solution, respectively dot them on the same high-efficiency silica gel G thin layer plate, develop with petroleum ether (60 ～ 90 ℃) - ethyl acetate (3:2) as the developing agent, develop with an exhibition distance of 8cm, take out, air dry, spray with 10% sulfuric acid ethanol solution, heat at 105 ℃ until the spots are clear. In the chromatogram of the test sample, spots with the same color appear at the corresponding position of the chromatogram of the control sample.
      Dendrobium fimbriae et al; Take 0.5g of powder of this product (fresh product is crushed after drying), add 25ml of methanol, sonicate for 45 minutes, filter, evaporate the filtrate, add 5ml of methanol to dissolve the residue as the test solution. In addition, take dendrobiol reference substance and add methanol to make a solution containing 0.2mg per 1ml as the reference solution. Test according to thin-layer chromatography (general rule 0502), pipette 5-10 μ l of the above test solution and 5 μ l of the control solution, respectively, onto the same high-efficiency silica gel G thin-layer plate, develop with petroleum ether (60-90 ℃) - ethyl acetate (3:2) as the developing agent, develop with an exhibition distance of 8cm, take out, air dry, spray with 10% sulfuric acid ethanol solution, heat at 105 ℃ until the spots are clear. In the chromatogram of the test sample, spots with the same color appear at the corresponding position of the chromatogram of the control sample.
      ; Dendrobium officinale   Not more than 12.0% (the second method of general rule 0832).
      Total ash   Dendrobium officinale   .
      [content determination] Dendrobium nobile   Determine according to gas chromatography (general rule 0521).
      ; Db-1 capillary column (100% dimethyl polysiloxane as the stationary phase) (column length: 30m, inner diameter: 0.25mm, film thickness: 0.25 μ m), temperature programmed: the initial temperature was 80 ℃, and the temperature was increased to 250 ℃ at the rate of 10 ℃ per minute for 5 minutes; The injection port temperature was 250 ℃, and the detector temperature was 250 ℃. The number of theoretical plates shall not be less than 10000 according to the dendrobine peak.
      Correction factor determination   . Take an appropriate amount of dendrobine reference substance, weigh it accurately, add methanol to make a solution containing 50 μ g per 1ml as the reference solution. Accurately measure 2ml of the reference solution, place it in a 5ml measuring flask, precisely add 1ml of the internal standard solution, add methanol to the scale, shake well, suck 1 μ L, inject it into the gas chromatograph, and calculate the correction factor.
      ; Take about 0.25g of the powder (crushed after drying the fresh product) (passing through No. 3 screen), accurately weigh it, place it in a round bottomed flask, precisely add 25ml of 0.05% formic acid in methanol solution, weigh it, heat and reflux for 3 hours, cool it, weigh it again, use 0.05% formic acid in methanol solution to make up the lost weight, shake it well, and filter it. Accurately measure 2ml of continuous filtrate, put it into a 5ml volumetric flask, precisely add 1ml of internal standard solution, add methanol to the scale, shake well, suck 1 μ L, inject it into the gas chromatograph, and determine it.
      Calculated as a dry product, the content of dendrobine (c16h25no2) shall not be less than 0.40%.
      Dendrobium drumstick   Determine according to high-performance liquid chromatography (general rule 0512).
      ; Octadecylsilane bonded silica gel was used as filler; The mobile phase was acetonitrile-0.05% phosphoric acid solution (37:63); The detection wavelength is 230nm. The number of theoretical plates should not be less than 6000 according to the peak of maolanin.
      Preparation of reference solution   Take an appropriate amount of maolanin reference substance, weigh accurately, add methanol to make a solution containing 15 μ g per 1ml.
      Preparation of test solution   Take about 1g of the powder (crushed after drying the fresh product) (passing through the third sieve), weigh it accurately, and place it in a corked conical flask Precisely add 50ml of methanol, plug, weigh, soak for 20 minutes, sonicate (power 250W, frequency 40KHz) for 45 minutes, cool, weigh again, make up the lost weight with methanol, shake well, filter, and take the filtrate.
      ; Precisely suck 20 μ l of the reference solution and 20 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 maolanin (c18h22o5) shall not be less than 0.030%.
      Decoction pieces
      [processing] Dendrobium officinale   Remove residual roots, wash, cut into sections, and dry. .
      This product is a flat cylindrical or cylindrical segment. The surface is golden yellow, greenish yellow or brownish yellow, shiny, with deep longitudinal grooves or longitudinal edges, and some Tan nodes can be seen. . It has slight breath, mild taste or bitter taste, and is sticky when chewing.
      Fresh Dendrobium   A segment that is cylindrical or oblate. The diameter is 0.4 ～ 1.2cm. The surface is yellowish green, smooth or with longitudinal lines, and the meat is juicy. The breath is slight, the taste is slightly bitter and sweet, and the chewing is sticky.
      [identification] (except for the transverse section) [inspection] is the same as that of medicinal materials.
      [nature, taste and meridian tropism] sweet, slightly cold. Return to stomach and kidney channels.
      [functions and indications] it can benefit the stomach, generate fluid, nourish yin and clear away heat. It is used for fever and body injury, dry mouth and thirst, lack of stomach yin, less food and retching, persistent deficiency heat after illness, excessive Yin deficiency and fire, bone steaming and heat exhaustion, unclear eyesight, muscle and bone flaccidity.
      [usage and dosage] 6-12g; fresh product 15-30g.
      ; Store the fresh products in a cool and damp place to prevent freezing.


2、 Chemical constituents of Dendrobium
1. the stem of Dendrobium nobile contains 0.3% alkaloids, which have been isolated as follows:Dendrobine(dendrobine)， Nobilonine, 6-hydroxydendrobine, also known as dendramine, dendroxine, 6-hydroxydendroxine, 4-hydroxydendroxine, dendrobine, 3-hydroxy-2-oxydendrobine, etc. It is also reported that five quaternary ammonium alkaloids were isolated (with unknown location): n-methyldendrobinium, N-isopentenyl dendrobinium, dendrobine N-oxide, n-isopentenyl-6-hydroxydendrobinium..the main alkaloids were identified as n-methyldendrobinium, n-isopentenyl-6-hydroxydendrobinium, n-isopentenyl-6-hydroxydendrobinium, n-isopentenyl-6-hydroxydendrobinium, n-isopentenyl-6-hydroxydendrobinium, n-isopentenyl-6-hydroxydendrobinium, n-isopentenyl-6-hydroxydendrobinium, N-isopentenyl. The stem also contains nobilomethylene, dendrobin,β - sitosterol（β-sitosterol），Carotene（daucosterol）。
2. the stem of Dendrobium officinale contains shihunine, shihunidin,Dendrobiol(dendrophenol) and other alkaloids.
3. Dendrobium Lindl contains alkaloids such as hygrine, CIS and trans dendrochrysine.
4. the stem of Dendrobium verbenum contains 18 components of cis-p-hydroxycinnamic acid and trans-p-hydroxycinnamic acid, as well as 1 component of stigmasterols and 1 component of β - sitosterol.
In addition, Dendrobium Luohe contains dendrobine; Hook Dendrobium contains aduncin; Dendrobium roseum contains crepidine, crepidamine, dendrocrepine, isodendrocrepine and isocrepidamine, which were isolated in the past, are actually artificial products obtained in the process of extraction and segregation; The whole plant of Dendrobium officinale contains dendrofloroside, dendroflorin, Dendrobium fluorenodiphenol,Psoralen（psoralen）， Scopoletin methyl ether,oleanolic acid （oleanolic-acid），β - sitosterol。

3、 Pharmacological effects of Dendrobium
1. antipyretic effect: Dendrobium nobile extract has no antipyretic effect on rabbits with artificial fever. Dendrobine has certain analgesic and antipyretic effects, similar to but weaker than phenacetin.
2. effect on the activity of isolated intestine: 2.1. effect on the activity of isolated intestine of guinea pigs: mash the fresh medicinal materials, add 70% ethanol (1g and 4ml of fresh medicinal materials) to cold soak at room temperature for 15 days, filter and reduce the pressure to recover the ethanol to a small volume, prepare the extract with distilled water into 4G of fresh medicinal materials per 1ml, and put it in the refrigerator for standby. Take healthy guinea pigs weighing 300-400g, male or female, and cut off the ileum, about 3cm in each section. Record the intestinal tube activity with dc-001 type ex vivo organ tester (record more than 30 minutes after dosing). The amount of Taishi liquid in the bath is 30ml, and the heating is constant at 38 ± 0.5 ℃. There are 3-8 guinea pigs in each experiment, with 6-16 sections of intestinal tube. The results showed that when the concentration was 2.5%, Dendrobium nobile, Dendrobium tenuifolium and Dendrobium bicolor could excite the intestinal tract; The effect of Dendrobium lodgeum on intestinal motility was not obvious; Dendrobium officinale, Dendrobium fimbriae, Dendrobium tenuifolium, Dendrobium nigrum and Dendrobium sheathum inhibited the intestinal tract first, and returned to the pre dose level after a few minutes; Dendrobium hook slightly reduced the contraction amplitude of the intestinal tract, and Dendrobium bouquet significantly inhibited the activity of the intestinal tract.
2.2. Dendrobium nobile extract can excite the isolated rabbit intestine at low concentration, but inhibit it at high concentration.
2.3. Dendrobium extract can excite rabbits' intestine in small doses and inhibit rabbits' intestine in large doses.
2.4. dendrobine has inhibitory effect on isolated rabbit intestine.
3. effects on gastrointestinal propulsion in mice: liquid Ⅰ: take 1g of Arabic gum, dissolve it in 2ml of distilled water, mix it into a paste, add 0.5g of activated carbon, mix it well, add normal saline to dilute to 10ml, and mix it well. Drug solution II: the preparation method is the same as that of drug solution I, with Dendrobium nobile extract (the preparation is the same as before) replacing normal saline. Drug solution III: the preparation method is the same as that of drug solution I. use Dendrobium officinale extract (the preparation is the same as before) instead of raw salt water. Thirty 18-22g healthy mice, half male and half female, were randomly divided into three groups; ; The mice were administrated by gavage according to the weight of 0.4ml / 20g. At 30 minutes, the mice were sacrificed and immediately laparotomized. The digestive tract was completely removed from the pylorus to the end of the rectum without traction. The whole length was measured by tiling it on a wooden ruler, and the distance from the front of the charcoal powder to the pylorus was recorded. The percentage of the charcoal powder to the total length of the intestine was calculated. The average value of the whole group was taken for comparison. Dendrobium Chrysanthemi can significantly inhibit the gastrointestinal propulsion; Dendrobium has no obvious effect on gastrointestinal propulsion.
4. effect on peritoneal macrophages: the water decoction of Dendrobium nobile can improve the phagocytic ability of peritoneal macrophages to chicken red blood cells in mice by gavage for 6 days.
5. effect on cardiovascular system: Dendrobium nobile extract inhibited the isolated toad heart regardless of the concentration. There was no significant effect of vascular perfusion in the lower limbs of toads. .
6. effect on pathogenic microorganisms: tissue culture was used for screening test, and it was proved that Dendrobium nobile decoction can delay the cytopathic effect caused by orphan virus (echo11).
7. other effects: dendrobine has the effect of inhibiting respiration, large doses can cause convulsions, and amiodarone can resist detoxification; The isolated guinea pig uterus can be contracted.