Powdered Asian Ginseng
DEFINITION
Powdered Asian Ginseng is Asian Ginseng reduced to a fine or very fine powder. It contains NLT 0.2% of ginsenoside Rg1 and NLT 0.1% of ginsenoside Rb1, both calculated on the dried basis.
IDENTIFICATION
•  A. Thin-Layer Chromatographic Identification Test
Standard solution:  5 mg/mL each of arbutin and escin, in methanol
Sample solution:  1.0 g of Powdered Asian Ginseng in a 25-mL flask fitted with a reflux condenser. Add 10.0 mL of a mixture of methanol and water (7:3), 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 chromatographic silica gel, typically 20 cm long (TLC plates)
Application volume:  20 µL, as bands
Developing solvent system:  The upper layer of a mixture of butyl alcohol, ethyl acetate, and water (10:2.5:5) in an unsaturated chamber
Spray reagent:  Dissolve 0.5 mL of anisaldehyde in 10 mL of glacial acetic acid, and add 85 mL of methanol, mix, and carefully add 5 mL of sulfuric acid to this mixture.
Analysis 
Samples:  Standard solution and Sample solution
Develop the chromatograms until the solvent front has moved up about three-fourths of the length of the plate. Remove the plate from the chamber, mark the solvent front, and allow the plate to dry. Spray with Spray reagent. Heat the plate at 105–110 for 10 min, and examine the plate.
System suitability:  The Standard solution chromatogram shows, in the upper third, a brown zone corresponding to arbutin, and in the lower third, a gray zone corresponding to escin.
Acceptance criteria:  The Sample solution exhibits violet-gray zones corresponding to ginsenoside Rg1 in the upper portion and to ginsenoside Re in the middle and in between the zones corresponding to arbutin and escin in the Standard solution. A violet-gray zone corresponding to ginsenoside Rb1 is located at the same RF value as the gray zone corresponding to escin in the Standard solution. Other, less intense bands may be observed between the zones due to ginsenosides Rb1 and Re, and the zone closest to the origin corresponds to ginsenoside Rc. Other spots may be visible in the lower third of the chromatogram.
•  B. The retention times of the peaks for ginsenosides Rg1, Re, Rf, Rb1, Rc, and Rd in the Sample solution chromatogram correspond to those in the Standard solution, as obtained in the test for Content of Ginsenosides Rb1 and Rg1. The ratio of the peak area for ginsenoside Rb2 to the peak area for ginsenoside Rb1 is NLT 0.4 (differentiation from American Ginseng).
COMPOSITION
•  Content of Ginsenosides Rb1 and Rg1
Solution A:  Water
Solution B:  Acetonitrile and water (4:1)
Mobile phase:  See Table 1.
Table 1
Time
(min)
Solution A
(%)
Solution B
(%)
0 76 24
12 76 24
28 65 35
51.5 56.5 43.5
52.5 0 100
64.5 76 24
77 76 24
Diluent:  Alcohol and water (4:6)
Standard solution:  Transfer a quantity of USP Powdered Asian Ginseng Extract RS, equivalent to 2 mg of ginsenoside Rg1, to a suitable container, and dissolve in 10.0 mL of Diluent. [Note—The concentrations of ginsenoside Rg1 and ginsenoside Rb1 in this solution are not expected to be equal and are determined on the basis of the labeled quantities present in USP Powdered Asian Ginseng Extract RS. ]
Sample solution:  Transfer about 1.0 g of Powdered Asian Ginseng, accurately weighed, to a 100-mL, round-bottom flask fitted with a reflux condenser. Add 50 mL of a mixture of Diluent and a few grains of pumice, and 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.
Chromatographic system 
Mode:  LC
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
System suitability 
Sample:  Standard solution
Suitability requirements 
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
Analysis 
Samples:  Standard solution and Sample solution
Calculate the percentages of ginsenosides Rb1 and Rg1 in the portion of Powdered Asian Ginseng taken:
Result = (rU/rS) × CS × (V/W) × 100
rU== peak response of ginsenoside Rg1 or ginsenoside Rb1 from the Sample solution
rS== peak response of ginsenoside Rg1 or ginsenoside Rb1 from the Standard solution
CS== concentration of ginsenoside Rg1 or ginsenoside Rb1 in the Standard solution (mg/mL)
V== final volume of the Sample solution (mL)
W== weight of Powdered Asian Ginseng used to prepare the Sample solution (mg)
Acceptance criteria 
Ginsenoside Rg1 NLT 0.2% on the dried basis
Ginsenoside Rb1 NLT 0.1% on the dried basis
CONTAMINANTS
•  Heavy Metals, Method III 231: NMT 20 ppm
•  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 102 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.
SPECIFIC TESTS
•  Botanic Characteristics: Pale yellowish-brown powder with a slightly aromatic odor. When examined under a microscope, the powder shows the following: traces of cork composed of thin-walled polygonal cells but mainly with phelloderm on the outside; wide cortex of parenchymatous cells with numerous secretory canals arranged in concentric zones; parenchymatous xylem with nonlignified tracheids and slightly lignified vessels with spiral and reticulate thickening, isolated or in small groups; small granules of starch 0.5–1.0 µm in diameter in all of the parenchymatous cells; and occasional cluster crystals of calcium oxalate in the cells of the central region.
•  Loss on Drying 731: Dry 1.0 g of finely Powdered Asian Ginseng at 105 for 2 h: it loses NMT 12.0% of its weight.
•  Articles of Botanical Origin, Total Ash 561: NMT 8.0%, determined on 1.0 g of finely Powdered Asian Ginseng
ADDITIONAL REQUIREMENTS
•  Packaging and Storage: Preserve in well-closed containers, and store in a cool, dry place.
•  Labeling: The label states the Latin binomial and, following the official name, the part of the plant source from which the article was derived.
•  USP Reference Standards 11
USP Powdered Asian Ginseng Extract RS
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Monograph Maged H. Sharaf, Ph.D.
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2021 Radhakrishna S Tirumalai, Ph.D.
Principal Scientific Liaison
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2022 Radhakrishna S Tirumalai, Ph.D.
Principal Scientific Liaison
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