Packaging and storage—
Preserve in well-closed containers, protected from light and moisture.
Labeling—
The label states the Latin binominal name and, following the official name, the part of the plant contained in the article.
Botanic characteristics—
Macroscopic—
Ginger occurs in horizontal, laterally flattened, sympodially branching pieces. Whole rhizomes are 5 to 15 cm long, 1.5 to 6 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.
Histology:
Starch abundant in the thin-walled ground tissue, as flattened, ovate to subrectangular, transversely striated, simple granules, each with the hilum in a projection toward one end, mostly up to about 50 µm long and up to about 25 µm wide and 7 µm thick. Oleoresin cells, with suberised cell walls and yellow contents, numerous in the ground tissue—pigment cells with dark, reddish brown contents occurring either singly in the ground tissue or in axial rows accompanying the vascular bundles. Irregularly shaped, thin-walled fibers with delicate transverse septa, yielding only slightly the reaction characteristic of lignin. Vessels with spiral or reticulate thickening in the scattered vascular bundles not yielding the reaction characteristic of lignin. In the unscraped ginger, varying amounts of cork, composed of thin-walled cells. Sclereids and calcium oxalate crystals absent.
Identification—
A:
Pulverize about 5 g of Ginger. To about 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 minutes. Filter, and add a few drops of
ammonium oxalate TS to the filtrate: not more than a slight turbidity is produced.
B:
Dissolve about 50 mg of the residue obtained in the test for
Alcohol-soluble extractives 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 so obtained, add 5 mL of sulfuric acid solution (7.5 in 10.0) and about 5 mg of vanillin. Allow to stand for 15 minutes, and add an equal volume of water: the solution turns azure blue.
C:
Thin-Layer Chromatographic Identification Test 
201
—
Adsorbent:
0.50-mm layer of chromatographic silica gel mixture.
Test solution—
Pulverize about 5 g of Ginger. Transfer about 0.2 g of pulverized sample to a test tube, add 5 mL of methanol, shake for 30 minutes, and centrifuge. Apply the supernatant to the plate.
Application volume:
20 µL.
Developing solvent system:
a mixture of ether and hexanes (7:3).
Procedure—
Proceed as directed in the chapter. A spot due to gingerols occurs at an RF value of about 0.2 and a spot of shogaols may occur at an RF value of about 0.4. [NOTE—The chromatograms of the Test solution and the Standard solution may exhibit other spots in the upper region and at the origin of the plate.]
Microbial enumeration 2021—
The total bacterial count does not exceed 10,000 cfu per g. The total combined molds and yeasts count does not exceed 100 cfu per g, and it meets the requirements of the tests for absence of
Salmonella species,
Escherichia coli, and
Staphylococcus aureus.
Limit of shogaols—
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 about the following retention times, relative to 1.0 for capsaicin: 1.86 for 6-shogaol, 4.22 for 8-shogaol and 5.76 for 10-shogaol. Calculate the percentage of shogaols,
B, in the portion of the residue from the test for
Alcohol-soluble extractives taken for the
Test preparation in the test for
Content of gingerols and gingerdiones by the formula:
1000(C / W)(rU / rS),
in which
C is the concentration, in mg per mL, of
USP Capsaicin RS in the
Standard preparation; W is the weight, in mg, of the residue from the test for
Alcohol-soluble extractives taken for the
Test preparation; rU is the sum of the peak responses due to shogaols as calculated above; and
rS is the peak response due to capsaicin obtained from the
Standard preparation: not more than 4.0% is found. Calculate the percentage of shogaols in the Ginger rhizome by the formula:
EB / 100,
in which
E is the percentage of alcohol-soluble extractive found in the test for
Alcohol-soluble extactives; and
B is as defined above: not more than 0.18% of shogaols is found.
Content of gingerols and gingerdiones—
Mobile phase—
Prepare a filtered and degassed mixture of acetonitrile, dilute phosphoric acid (1 in 1000), and methanol (55:44:1). Make adjustments if necessary (see
System Suitability under
Chromatography 621).
Standard preparation—
Dissolve an accurately weighed quantity of
USP Capsaicin RS in methanol to obtain a solution having a known concentration of about 0.25 mg per mL.
Test preparation—
Transfer about 50 mg, accurately weighed, of the residue (equivalent to about 9 mg of gingerols) retained from the test for
Alcohol-soluble extractives to a 10-mL volumetric flask, dissolve in and dilute with methanol to volume, and mix.
System suitability solution—
Mix 1.0 mL of the Standard preparation with 1.0 mL of the Test preparation.
Chromatographic system (see Chromatography 621)—
The liquid chromatograph is equipped with a 282-nm detector and a 4.6-mm × 25-cm column that contains packing L1. The flow rate is about 1.0 mL per minute. Chromatograph the
Standard preparation, and record the peak responses as directed for
Procedure: the relative standard deviation for replicate injections is not more than 2.5%. Chromatograph the
System suitability solution, and record the peak responses as directed for
Procedure: the relative retention times are about 0.8 for 6-gingerol, 1.0 for capsaicin, 1.51 for 8-gingerol A, 2.21 for 8-gingerol B, 2.46 for 6-gingerdiol, 2.60 for 6-gingerdione, 3.35 for 10-gingerol, and 5.16 for 8-gingerdione; and the resolution,
R, between 6-gingerol and capsaicin is not less than 1.0.
Procedure—
Separately inject equal volumes (about 10 µL) of the
Standard preparation and the
Test preparation into the chromatograph, and allow the
Test preparation to elute for not less than seven times the retention time of capsaicin. Record the chromatograms, and measure all of the peak responses. Calculate the percentage of gingerols and gingerdiones,
A, in the portion of the residue from the test for
Alcohol-soluble extractives taken for the
Test preparation by the formula:
1000(C / W)(rU / rS),
in which
C is the concentration, in mg per mL, of
USP Capsaicin RS in the
Standard preparation; W is the weight, in mg, of the residue from the test for
Alcohol-soluble extractives taken for the
Test preparation; rU is the sum of the peak responses due to gingerols and gingerdiones as calculated above; and
rS is the capsaicin peak response obtained from the
Standard preparation: not less than 18% of gingerols and gingerdiones is found. Calculate the percentage of gingerols and gingerdiones in the Ginger rhizome by the formula:
EA / 100,
in which
E is the percentage of alcohol-soluble extractives obtained in the test for
Alcohol-soluble extractives; and
A is as defined above: not less than 0.8% is found.
: not less than 4.5% is found. Save the residue for use in Identification test B and the tests for Content of gingerols and gingerdiones and Limit of shogaols.