Ginger is the dried rhizome of Zingiber officinale Roscoe (Fam. Zingiberaceae), scraped, partially scraped, or unscraped. It is known in commerce as unbleached ginger.
Analysis: Pulverize 5 g of Ginger. To 1 g of the pulverized 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.
Sample: 50 mg of the residue obtained in the test for Articles of Botanical Origin, Alcohol-Soluble Extractives
Analysis: Dissolve the Sample in 25 mL of water, and extract this solution 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 and Gingerdiones.
Sample solution: Pulverize 5 g of Ginger. Transfer 0.2 g of pulverized 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 the Sample solution and Standard solution A; 40 µL for Standard solution B
Developing solvent system: Ether and hexanes (7:3)
Spray reagent: 10% sulfuric acid in alcohol
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 100105 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. A spot of shogaols may occur at an RF value of 0.4, corresponding to those shown in the chromatogram of Standard solution B. [NoteThe chromatograms of the Sample solution and Standard solution A may exhibit other spots in the upper region and at the origin of the plate. ]
• Content of Gingerols and Gingerdiones
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.
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: Use the filtrate retained from the test for Articles of Botanical Origin, Alcohol-Soluble Extractives.
Detector: UV 282 nm
Column: 4.6-mm × 25-cm; packing L1
Flow rate: 1 mL/min
Injection size: 25 µL
Samples: Standard solution and System suitability solution
[NoteThe relative retention times for 6-gingerol, capsaicin, and 6-shogaol are about 0.8, 1.0, and 1.9, respectively, System suitability solution. ]
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%, Standard solution
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 percentage of gingerols and gingerdiones in the sample taken:
Result = (rT/rS) × (CS/W) × 10
Acceptance criteria: NLT 0.8%
• Articles of Botanical Origin, Pesticide Residues 561: Meets the requirements
• Microbial Enumeration Tests 2021: The total bacterial count does not exceed 105 cfu/g; the total combined molds and yeasts count does not exceed 103 cfu/g; the bile-tolerant Gram-negative bacteria count does not exceed 103 cfu/g.
• Absence of Specified Microorganisms 2022: It meets the requirements of the tests for absence of Salmonella species and Escherichia coli.
• Botanic Characteristics
Macroscopic: Ginger occurs in horizontal, laterally flattened, sympodially branching pieces. Whole rhizomes are 515 cm long, 1.56 cm wide, and up to 2 cm thick, sometimes split longitudinally, pale yellowish buff or light brown externally, longitudinally striated, somewhat fibrous; branches flattish, obovate, short, about 2 cm long, each ending with a depressed stem scar; fracture, short with projecting fibers, or sometimes resinous; internally yellowish brown, showing a yellow endodermis separating the narrow cortex from the wide stele, and numerous yellowish points, secretion cells and numerous bigger greyish points, vascular bundles, scattered on the whole surface. The unscraped rhizome shows in addition an outer layer of dark brown cork. Morphological characteristics of different varieties and forms of Ginger from different geographical areas are listed in Table 1 of the general information chapter Supplemental Information for Articles of Botanical Origin 2030.
Histology: The scraped rhizome in transverse section shows a cortex composed of multiple layers of parenchyma cells rich in simple, large, flattened, ovoid or sack-shaped starch granules, 515 µm wide and 3060 µm long having an eccentric hilum, some showing faint transverse striations. The cortex also shows numerous oleoresin cells with a yellow or yellowish-brown content and scattered collateral vascular bundles; a single layer of endodermal cells free from starch; a wide central stele composed of parenchyma cells rich in starch and oleoresin cells similar to those of the cortex, and containing scattered collateral vascular bundles, some enclosed in a sheath of septate nonlignified fibers with wide lumen. In addition to the above, the unscraped rhizome shows an outer zone of dark brown cork cells.
• Limit of Shogaols
Analysis: From the chromatograms obtained in the test for Content of Gingerols and Gingerdiones, calculate the sum of the peak responses due to shogaols, occurring at 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 shogaols in the portion taken:
Result = (rT/rS) × (CS/W) × 10
Acceptance criteria: NMT 0.18%
• Articles of Botanical Origin, Alcohol-Soluble Extractives, Method 2 561
Analysis: 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. [NoteSave the residue for use in Identification test B and the remaining volume of the filtrate for the tests for Limit of Shogaols and Content of Gingerols and Gingerdiones. ]
Acceptance criteria: NLT 4.5% residue
• Articles of Botanical Origin, Content of Starch, Method 1 561: NLT 42%, Method Ia of the General Procedures being used
• Articles of Botanical Origin, Total Ash 561: NMT 8.0%
• Articles of Botanical Origin, Volatile Oil Content 561: NLT 1.8 mL/100 g
• Water Determination, Method Ia 921: NMT 10%
• Packaging and Storage: Preserve in well-closed containers, protected from light and moisture, and store in a cool area.
Change to read:• Labeling: The label states the Latin binominal and, following the official name, the part of the plant contained in the article. 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 Ginger Constituent Mixture RS
USP Powdered Ginger RS
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USP35NF30 Page 1317Pharmacopeial Forum: Volume No. 36(6) Page 1595