Herbal identification
This product has a square columnar shape, many branches, four longitudinal grooves, length 0.5 ~ 1m; surface green brown, rough; hard and brittle, cross-section of marrow or hollow. The leaves are opposite, crumpled, broken, and green-brown. The complete leaves show a deep crack after the flattening and the edges are serrated. Spikes are slender, with many florets. Odorless and bitter.
Microscopic identification
This product is greenish brown. Stem epidermal cells are long polygonal or rectangular, vertical wall more flat, with stomata. The pericentral wall of the lower epidermis cells is wavy, the stomatal infinitive or inequality, and 3 to 5 accessory cells. Adenosquamous head 4 cells, 23 to 58 μm in diameter; stalk single cells. Non-glandular hair cells. The pollen grains are round or quasi-circular triangles with a diameter of 24 to 35 μm, a smooth surface and 3 germination holes.
Physical and chemical identification
Take this product powder 2g, add 80% methanol 60ml, heat reflux for 1 hour, filtered, the filtrate evaporated, the residue was dissolved in 2ml methanol, as the test solution. Another verbena control medicine 2g, with the legal system as a reference drug solution. Take the ursolic acid reference substance and add methanol to make a solution containing 1 mg per 1 ml as the reference solution. According to the TLC test, 2 to 4 μl of each of the above three solutions were pipetted and spotted on the same silica gel G thin-layer board with sodium carboxymethyl cellulose as the binder, using chloroform-methanol-isopropanone (16:0.5: 0.25) as developing solvent, expand, remove and air dry. Spray a mixed solution of vanillin ethanol solution (1→100) and perchloric acid solution (3→100) (equal mixing when using) and heat at 105°C to the spot. Clear coloration. In the chromatogram of the test sample, the spots of the same color were respectively shown on the positions corresponding to the chromatograms of the reference drug and the reference substance.
Determination of content
Take this product coarse powder about 1g at the same time to take this product coarse powder to determine the moisture, accurately weighed, set with plug Erlenmeyer flask, accurately add anhydrous ethanol 30ml, weigh the weight, ultrasonic treatment for 1.5 hours, let cool, and then say Fixed weight, make up for loss with anhydrous ethanol
Weight, Shake well, Filtrate, Precise amount Take 15ml of filtrate, evaporate and dry. Residue is soaked with petroleum ether (30-60°C) 2 times, each time 15ml (immersed for about 2 minutes). Pour off the petroleum ether solution. Add residue. An appropriate amount of anhydrous ethanol was allowed to dissolve and transferred to a 5 ml volumetric flask and diluted to the mark. Shake it well as a test solution. Another accurately weighed ursolic acid reference substance, plus ethanol to make a solution containing 0.5mg per 1ml as a reference solution. According to the TLC test, 2 μl of the test solution and 1 μl of the control solution and 2 μl of the test solution were precisely pipetted and crossed at the same time on the same silica gel G plate, with cyclohexane-chloroform-ethyl acetate-glacial acetic acid (20: 5:8:0.1) as a developing agent, unfolded, taken out, air-dried, sprayed with 10% ethanolic sulphuric acid solution, heated at 110°C until the spots are clearly visible, removed, and covered with a glass plate of the same size on a thin layer plate, around Fix with tape and scan according to thin layer chromatography (Appendix VIB thin layer scan method). Wavelength: λs=525nm, λR=700nm. Measure the integrated value of the absorbance of the test sample and the absorbance of the reference substance. Calculate. . This product is based on dry products, containing ursolic acid (C30H48O3) shall not be less than 0.36%.
