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American Ginseng
» American Ginseng consists of the dried roots of Panax quinquefolius L. (Fam. Araliaceae). It contains not less than 4.0 percent of total ginsenosides, calculated on the dried basis.
Packaging and storage— Preserve in tight, light-resistant containers, and store protected from heat.
Labeling— The label states the Latin binomial and, following the official name, the parts of the plant contained in the article.
Botanic characteristics—
Macroscopic— Fusiform or cylindrical roots, sometimes branched, typically 1 to 10 cm, sometimes up to 20 cm in length and up to 2.5 cm in diameter at the crown, with one or more stem scars. Externally pale yellow to golden, rough-textured, with prominent horizontal rings and fine longitudinal ridges as a result of drying. Root scars or fine rootlets are present. If stem base is present, scales are thin and perishing (differs from P. ginseng, in which scales at base of stem are fleshy and persistent). Fracture is short; fractured surface is white to ivory, with distinct aromatic odor and rings of secretory canals present in secondary phloem.
HISTOLOGY—
Transverse section of root— Multiple layers of thin-walled cork cells are present. Secondary phloem is characterized by conspicuous air lacunae; abundant, starch-containing storage parenchyma; few sieve elements, found in small groupings; and rings of schizogenous secretory canals. Each secretory canal is lined with 6 to 8 epithelial cells that lack starch. Xylem is characterized by abundant starch-containing storage parenchyma and a few tracheary elements, composed of nonlignified tracheids and slightly lignified spiral or reticulated vessels lacking secretory canals and found in isolation or in small groupings. Druse crystals are sometimes present within vascular parenchyma cells. Diarch or triarch primary xylem is in center of root.
Identification—
A: Thin-Layer Chromatographic Identification Test 201—
Test solution— Finely powder American Ginseng. Transfer 1.0 g of this powder to a 25-mL flask fitted with a reflux condenser. Add 10.0 mL of a mixture of water and methanol (13:7), and heat under reflux for 15 minutes. Cool, filter, and dilute the filtrate with methanol to 10.0 mL.
Standard solution 1: a solution of USP Powdered American Ginseng Extract RS in methanol having a known concentration of about 20 mg per mL.
Standard solution 2: a solution of USP Powdered Asian Ginseng Extract RS in methanol having a known concentration of about 20 mg per mL.
Application volume: 20 µL.
Developing solvent system 1— Prepare a mixture of chloroform, methanol, and water (13:7:2), and use the lower phase.
Developing solvent system 2— Prepare a mixture of water, butyl alcohol, and ethyl acetate (5:4:1), and use the upper phase.
Spray reagent— Dissolve 0.5 mL of anisaldehyde in 10 mL of glacial acetic acid, add 85 mL of methanol, mix, carefully add 5 mL of sulfuric acid, and mix.
Procedure— Proceed as directed in the chapter. Develop the chromatograms in a chamber containing Developing solvent system 1 until the solvent front has moved about 10.5 cm from the origin. Remove the plates from the chromatographic chamber, and allow to dry. Turn the plates 90, and develop in a chamber containing Developing solvent system 2 until the solvent front has moved about 10.5 cm from the origin. Remove the plates from the chromatographic chamber, and allow to dry. Spray with Spray reagent. Heat the plates at 105 to 110 for about 10 minutes, and examine. The order, from top to bottom, of ginsenosides on the chromatographic plates is Rg2 (on left) and Rg1 (on right), Rf, Re, Rd, Rc, Rb2 (on left) and Rb1 (on right), and Ro. Ginsenosides Rg2, Rg1, Rf, Re, and Rd are found on the upper half of the plates; the remaining ginsenosides are found on the lower half after chromatographing with Developing solvent system 2. The chromatogram obtained from Standard solution 1 does not exhibit a spot for ginsenoside Rf. The chromatogram obtained from Standard solution 2 exhibits a spot for ginsenoside Rf. The spots on the chromatogram from the Test solution correspond to those on the chromatogram from Standard solution 1.
B: The retention times of the peaks for ginsenosides Rg1, Re, Rb1, Rb2, Rc2, and Rd in the chromatogram of the Test solution correspond to those in the chromatogram of Standard solution 1, as obtained in the test for Content of ginsenosides. The ratio of the peak reaponse for Rb2 to the peak response for Rb1 is less than 0.4, and the ratio of the peak response for Rg1 to the peak response for Rb1 is less less than 0.3. The chromatogram shows no significant peak at the retention time corresponding to that for ginsenoside Rf in the chromatogram of Standard solution 2, as obtained in the test for Content of ginsenosides.
Microbial enumeration 2021: meets the requirements under Asian Ginseng.
Loss on drying 731— Dry 1 g of it, finely powdered and accurately weighed, at 105 for 2 hours: it loses not more than 10.0%.
Foreign organic matter 561: not more than 2.0%.
Total ash 561: not more than 8%.
Pesticide residues 561: meets the requirements.
Content of ginsenosides—
Solution A, Solution B, Mobile phase, and Chromatographic system— Proceed as directed in Content of ginsenosides under Powdered Asian Ginseng Extract.
Standard solution 1— Transfer an accurately weighed quantity of USP Powdered American Ginseng Extract RS, equivalent to about 2 mg of ginsenoside Rb1, to a suitable container. Dissolve in 10.0 mL of a mixture of water and alcohol (6:4).
Standard solution 2— Transfer an accurately weighed quantity of USP Powdered Asian Ginseng Extract RS, equivalent to about 2 mg of ginsenoside Rg1, to a suitable container. Dissolve in 10.0 mL of a mixture of water and alcohol (6:4).
Test solution— Reduce about 100 g of American Ginseng to a powder, and transfer about 1.0 g of the powder, accurately weighed, to a 100-mL round-bottom flask fitted with a reflux condenser. Add 50 mL of a mixture of water and alcohol (6:4) and a few grains of pumice, boil on a water bath under reflux for 1 hour, cool, and filter. Wash the flask and the residue with 20 mL of a mixture of water and alcohol (6:4), and pass through the same filter. Combine the filtrates, and evaporate in a rotary evaporator at 50 to dryness. Dissolve the residue in 10.0 mL of a mixture of water and alcohol (6:4).
Procedure— Separately inject equal volumes (about 10 µL) of each Standard solution and the Test solution into the chromatograph, and record the chromatograms. Identify ginsenosides Rg1, Re, Rb1, Rc, Rb2, and Rd in the Standard solutions and the Test solution by comparing the chromatograms with the Reference Chromatogram provided with USP Powdered American Ginseng Extract RS, and measure the peak responses. Calculate the percentages of individual ginsenosides in the portion of American Ginseng taken by the formula:
1000(C/W)(rU / rS),
in which C is the concentration, in mg per mL, of ginsenoside Rg1, Re, Rb1, Rc, Rb2, or Rd in the appropriate Standard solution; W is the weight, in mg, of American Ginseng taken to prepare the Test solution; and rU and rS are the peak responses of ginsenoside Rg1, Re, Rb1, Rc, Rb2, or Rd obtained from the Test solution and the appropriate Standard solution, respectively. Calculate the percentage of total ginsenosides in the portion of American Ginseng taken by adding the individual percentages.
Auxiliary Information— Staff Liaison : Maged H. Sharaf, Ph.D., Senior Scientist
Expert Committee : (DSB05) Dietary Supplements - Botanicals
USP29–NF24 Page 2336
Pharmacopeial Forum : Volume No. 30(2) Page 563
Phone Number : 1-301-816-8318