American Ginseng consists of the dried roots of Panax quinquefolius L. (Fam. Araliaceae). It contains NLT 4.0% of total ginsenosides, calculated on the dried basis.
• A. Thin-Layer Chromatographic Identification Test
Standard solution A: 20 mg/mL of USP Powdered American Ginseng Extract RS in methanol
Standard solution B: 20 mg/mL of USP Powdered Asian Ginseng Extract RS in methanol
Sample solution: Transfer about 1.0 g of finely powdered American Ginseng to a 25-mL flask fitted with a reflux condenser. Add 10.0 mL of a mixture of methanol and water (7:13), and heat under reflux for 15 min. Cool, filter, and dilute the filtrate with methanol to 10.0 mL.
Adsorbent: 0.25-mm layer of silica gel, typically 20 cm long (TLC plates)
Application volume: 20 µL
Developing solvent system A: Chloroform, methanol, and water (13:7:2). Use the lower phase.
Developing solvent system B: Butyl alcohol, ethyl acetate, and water (4:1:5). 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, and carefully add 5 mL of sulfuric acid.
Samples: Standard solution A, Standard solution B, and Sample solution
Develop in a chamber containing Developing solvent system A until the solvent front has moved 10.5 cm from the origin. Remove the plates, and allow to dry. Turn the plates 90, and develop in a chamber containing Developing solvent system B until the solvent front has moved 10.5 cm from the origin. Remove the plates, and allow to dry. Spray with Spray reagent. Heat the plates at 105110 for 10 min, and examine.
Suitability requirements: 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 B. Standard solution A does not exhibit a spot for ginsenoside Rf. Standard solution B exhibits a spot for ginsenoside Rf.
Acceptance criteria: The spots from the Sample solution correspond to those from Standard solution A.
• B. The retention times of the peaks for ginsenosides Rg1, Re, Rb1, Rb2, Rc2, and Rd of the Sample solution correspond to those of Standard solution A, as obtained in the test for Content of Ginsenosides. The ratio of the peak responses for ginsenosides Rb2 to Rb1 is less than 0.4, and the ratio of the peak responses for ginsenosides Rg1 to Rb1 is less than 0.3. The chromatogram shows no significant peak at the retention time corresponding to that for ginsenoside Rf of Standard solution B, as obtained in the test for Content of Ginsenosides.
• Content of Ginsenosides
Solution A: Water
Solution B: Acetonitrile and water (4:1)
Mobile phase: See Table 1.
Diluent: Alcohol and water (4:6)
Standard solution A: Transfer a quantity of USP Powdered American Ginseng Extract RS, equivalent to about 2 mg of ginsenoside Rb1, to a suitable container, and dissolve in 10.0 mL of Diluent.
Standard solution B: Transfer a quantity of USP Powdered Asian Ginseng Extract RS, equivalent to about 2 mg of ginsenoside Rg1, to a suitable container, and dissolve in 10.0 mL of Diluent.
Sample solution: Reduce 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 Diluent and a few grains of pumice, boil on a water bath under reflux for 1 h, cool, and filter. Wash the flask and the residue with 20 mL of Diluent, 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 Diluent.
Detector: UV 203 nm
Analytical column: 4.6-mm × 15-cm; 3-µm packing L1
Guard column: 4.6-mm × 2.0-cm; packing L1
Column temperature: 25
Flow rate: 1.5 mL/min
Injection size: 10 µL
Sample: Standard solution B
Chromatogram similarity: The chromatogram is similar to the Reference Chromatogram provided with the lot of USP Powdered Asian Ginseng Extract RS being used.
Relative standard deviation: NMT 2.0%, determined for the sum of the peak areas for the 6 major ginsenosides, in replicate injections
Samples: Standard solution A, Standard solution B, and Sample solution
Identify ginsenosides Rg1, Re, Rb1, Rc, Rb2, and Rd in the Standard solutions and the Sample 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:
Result = (rU/rS) × CS × (V/W) × 100
Calculate the percentage of total ginsenosides in the portion of American Ginseng taken by adding the individual percentages.
Acceptance criteria: NLT 4.0% of total ginsenosides on the dried basis
• Heavy Metals, Method III 231: NMT 20 ppm
• Articles of Botanical Origin, General Method for Pesticide Residues Analysis 561: Meets the requirements
• Microbial Enumeration Tests 2021: The total aerobic microbial count does not exceed 104 cfu/g. The total combined molds and yeasts count does not exceed 100 cfu/g.
• Microbiological Procedures for Absence of Specified Microorganisms 2022: It meets the requirements of the tests for absence of Salmonella species, Escherichia coli, and Staphylococcus aureus.
• Botanic Characteristics
Macroscopic: Fusiform or cylindrical roots, sometimes branched, typically 110 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.
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 68 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.
• Loss on Drying 731: Dry 1 g of it, finely powdered, at 105 for 2 h: it loses NMT 10.0% of its weight.
• 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.
• USP Reference Standards 11
USP Powdered American Ginseng Extract RS
USP Powdered Asian Ginseng Extract RS
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