Ginger Capsules
DEFINITION
Ginger Capsules are prepared from Powdered Ginger and contain NLT 90.0% and NMT 110.0% of the labeled amount of gingerols, gingerdiones, and shogaols, and NLT 90.0% of the labeled amount of volatile oil.
IDENTIFICATION
•  A.
Analysis:  Pulverize an amount of the contents of Capsules equivalent to 5 g of ginger. To an amount equivalent to 1 g of ginger add 5 mL of dilute acetic acid, prepared by diluting 1 part of glacial acetic acid with 1 part of water, and shake for 15 min. Filter, and add a few drops of ammonium oxalate TS to the filtrate.
Acceptance criteria:  NMT a slight turbidity is produced.
•  B.
Sample (see Articles of Botanical Origin 561, Alcohol-Soluble Extractives, Method 2):  Collect the filtrate in a 100-mL volumetric flask, and dilute with alcohol to volume. Evaporate 50 mL of the filtrate at a temperature not exceeding 90. Use 50 mg of the residue for the test.
Analysis:  Dissolve the Sample in 25 mL of water, and extract with two 15-mL portions of ether. Combine the ether extracts, and evaporate in a porcelain dish. To the residue add 5 mL of sulfuric acid solution (7.5 in 10.0) and 5 mg of vanillin. Allow to stand for 15 min, and add an equal volume of water.
Acceptance criteria:  The solution turns azure blue.
•  C. Thin-Layer Chromatographic Identification Test
Standard solution A:  Proceed as directed for the Sample solution, except to use 0.2 g of USP Powdered Ginger RS.
Standard solution B:  Use the System suitability solution, prepared as directed in the test for Content of Gingerols, Gingerdiones, and Shogaols.
Sample solution:  Pulverize an amount of the contents of Capsules equivalent to 5 g of ginger. Transfer an amount equivalent to 0.2 g of ginger to a test tube, add 5 mL of methanol, shake for 30 min, and centrifuge. Apply the supernatant to the plate.
Adsorbent:  0.50-mm layer of chromatographic silica gel mixture
Application volume:  20 µL for Standard solution A and the Sample solution; 40 µL for Standard solution B
Developing solvent system:  Ether and hexanes (7:3)
Spray reagent:  10% sulfuric acid in alcohol
Analysis 
Samples:  Standard solution A, Standard solution B, and Sample solution
Proceed as directed in the chapter. Examine the plate under UV light at 254 nm. Spray the plate with Spray reagent, heat at 100–105 for 10 min, and examine under daylight.
Acceptance criteria:  The chromatogram of the Sample solution exhibits a spot due to gingerols that occurs at an RF value of 0.2, and a spot of shogaols may occur at an RF value of 0.4, corresponding to those shown in the chromatogram of Standard solution B. [Note—The chromatograms of Standard solution A and the Sample solution may exhibit other spots in the upper region and at the origin of the plate. ]
STRENGTH
•  Content of Gingerols, Gingerdiones, and Shogaols
Solution A:  Acetonitrile, dilute phosphoric acid (1 in 1000), and methanol (55:44:1)
Solution B:  Acetonitrile
Mobile phase:  Use Solution A for NLT seven times the retention time of capsaicin.
Column washing:  After each chromatographic run, wash the column, using Table 1.
Table 1
Time
(min)
Solution A
(%)
Solution B
(%)
0 100 0
2 0 100
12 0 100
14 100 0
29 100 0
Standard solution:  0.1 mg/mL of USP Capsaicin RS in methanol
System suitability solution:  Reconstitute the content of 1 vial of USP Ginger Constituent Mixture RS in 1 mL of the Standard solution.
Sample solution:  Mix and finely powder the contents of NLT 20 Capsules, and transfer an amount equivalent to 2.0 g of powdered ginger to a glass-stoppered conical flask. Add 50 mL of alcohol, insert a stopper into the flask, and macerate for 24 h, shaking frequently during the first 8 h, and then allowing to stand for 18 h. Filter, and use the filtrate.
Chromatographic system 
Mode:  LC
Detector:  UV 282 nm
Column:  4.6-mm × 25-cm; packing L1
Flow rate:  1 mL/min
Injection size:  25 µL
System suitability 
Samples:  Standard solution and System suitability solution
[Note—The relative retention times for 6-gingerol, capsaicin, and 6-shogaol are about 0.8, 1.0, and 1.9, respectively, System suitability solution. ]
Suitability requirements 
Resolution:  NLT 3.0 between the 6-gingerol and capsaicin peaks and NLT 10.0 between the capsaicin and 6-shogaol peaks, System suitability solution
Tailing factors:  NMT 2.0 for the 6-gingerol, capsaicin, and 6-shogaol peaks, System suitability solution
Relative standard deviation:  NMT 2.5% for the capsaicin peak for replicate injections, Standard solution
Analysis 
Samples:  Standard solution, Sample solution, and System suitability solution
Calculate the sum of the peak responses due to gingerols and gingerdiones occurring at about the following retention times relative to 1.0 for capsaicin: 0.8 for 6-gingerol, 1.5 for 8-gingerol A, 2.2 for 8-gingerol B, 2.5 for 6-gingerdiol, 2.6 for 6-gingerdione, 3.4 for 10-gingerol, and 5.2 for 8-gingerdione.
Calculate the sum of the peak responses due to shogaols, occurring at about the following retention times, relative to 1.0 for capsaicin: 1.9 for 6-shogaol, 4.2 for 8-shogaol, and 5.8 for 10-shogaol.
Calculate the percentage of the labeled amount of gingerols, gingerdiones, and shogaols in the portion of Capsules taken:
Result = (rT/rS) × CS × (V/WU) × (AWC/L) × 100
rT== sum of the peak responses for gingerols, gingerdiones, and shogaols from the Sample solution
rS== peak response of capsaicin from the Standard solution
CS== concentration of USP Capsaicin RS in the Standard solution (mg/mL)
V== final volume of the Sample solution (mL)
WU== weight of the portion of Capsules taken (mg)
AWC== average weight of the Capsule content (mg)
L== labeled amount of gingerols, gingerdiones, and shogaols (mg/Capsule)
Acceptance criteria:  90.0%–110.0% of the labeled amount of gingerols, gingerdiones, and shogaols
Calculate the amount (G0), in mg, of 6-gingerol in each Capsule taken:
G0 = (rU/rS) × (CS/W) × V × A
rU== peak response of 6-gingerol from the Sample solution
rS== peak response of capsaicin from the Standard solution
CS== concentration of USP Capsaicin RS in the Standard solution (mg/mL)
W== weight of powdered ginger used in the preparation of the Sample solution (g)
V== final volume of the Sample solution (mL)
A== average Capsule fill weight (g)
•  Articles of Botanical Origin, Volatile Oil Determination 561
Sample:  Finely powder a quantity of Capsules, equivalent to 100 g of powdered ginger.
Acceptance criteria:  NLT 1.4 mL/100 g (NLT 90.0% of the labeled amount of volatile oil)
PERFORMANCE TESTS
•  Disintegration and Dissolution 2040: Meet the requirements for Dissolution
Medium:  0.1 N hydrochloric acid; 500 mL
Apparatus 2:  75 rpm
Time:  60 min
[Note—In each dissolution vessel, place a number of Capsules equivalent to 20 mg of the labeled amounts of gingerols, gingerdiones, and shogaols. ]
Solution A, Solution B, Mobile phase, Column washing, System suitability solution, Chromatographic system, and System suitability: 
Proceed as directed in the test for Content of Gingerols, Gingerdiones, and Shogaols.
Standard stock solution:  Use the Standard solution prepared in the test for Content of Gingerols, Gingerdiones, and Shogaols.
Standard solution:  0.025 mg/mL of USP Capsaicin RS from Standard stock solution in Medium
Sample solution:  Transfer an aliquot of solution from each dissolution vial to a suitable vial. Allow to stand for 5 min so that the powder settles into the suspension, or centrifuge to obtain a clear supernatant. Pass through a membrane filter of 0.45-µm or finer pore size.
Analysis 
Samples:  Standard solution and Sample solution
[Note—Allow the Sample solution to elute for NLT three times the retention time of capsaicin. ]
Calculate the quantity, G, in mg, of 6-gingerol dissolved from each Capsule taken:
G = (rU/rS) × (C/N) × V
rU== peak response of 6-gingerol from the Sample solution
rS== peak response of capsaicin from the Standard solution
C== concentration of USP Capsaicin RS in the Standard solution (mg/mL)
N== number of Capsules in each vessel
V== volume of Medium; 500 mL
Calculate the percentage of the relative amount of 6-gingerol dissolved:
Result = (G/G0) × 100
G0== content of 6-gingerol in each Capsule, as determined in the test for Content of Gingerols, Gingerdiones, and Shogaols (mg)
Tolerances:  NLT 60% of the content of 6-gingerol (C17H26O4) is dissolved.
•  Weight Variation 2091: Meet the requirements
ADDITIONAL REQUIREMENTS
•  Packaging and Storage: Preserve in well-closed containers, and store at controlled room temperature.
Change to read:
•  Labeling: The label states the Latin binomial and, following the official name, the part of the plant from which the article was prepared. The label also indicates the content of gingerols, gingerdiones, and shogaols, in mg per Capsule, and the content of volatile oil, in µL per Capsule. This article is exempted from the requirements of the General Notices with respect to the pregnancy and lactation statement (section 10.40.50, Labeling Botanical-Containing Products).USP35
•  USP Reference Standards 11
USP Capsaicin RS Click to View Structure
USP Ginger Constituent Mixture RS
USP Powdered Ginger RS
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Topic/Question Contact Expert Committee
Monograph Maged H. Sharaf, Ph.D.
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USP35–NF30 Page 1320
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