|
Powdered Turmeric
DEFINITION
Powdered Turmeric is Turmeric reduced to a fine or very fine powder.
IDENTIFICATION
• A. Thin-Layer Chromatographic Identification Test
Standard solution:
0.2 mg/mL of USP Curcuminoids RS in acetone
Sample solution:
Transfer about 0.2 g of Powdered Turmeric to a test tube, add 3 mL of acetone, sonicate for 30 min, and centrifuge. Use the supernatant.
Adsorbent:
0.25-mm layer of chromatographic silica gel mixture, typically 20 cm long (TLC plates)
Application volume:
10 µL, as bands
Developing solvent system:
Chloroform, methanol, and formic acid (96:4:1)
Analysis
Samples:
Standard solution and Sample solution
Apply the samples as bands to a suitable thin-layer chromatographic plate (see Chromatography
Acceptance criteria:
The Sample solution chromatogram shows yellowish-brown bands due to bisdesmethoxycurcumin, desmethoxycurcumin, and curcumin at RF values of about 0.4, 0.6, and 0.7, respectively, corresponding in position and color to those obtained from the Standard solution.
• B.
The retention times of the peaks for curcumin, desmethoxycurcumin, and bisdesmethoxycurcumin of the Sample solution chromatogram correspond to those of the Standard solution for the appropriate USP Reference Standard, as obtained in the test for Content of Curcuminoids.
COMPOSITION
• Content of Curcuminoids
Mobile phase:
Tetrahydrofuran and 1 mg/mL of citric acid in water (4:6)
[NoteSonication may be necessary to dissolve the Reference Standard in each Standard solution; all solutions should be passed through a filter of 0.45-µm pore size before injection. USP Curcumin RS, USP Desmethoxycurcumin, and USP Bisdesmethoxycurcumin RS can also be prepared in one standard solution containing the final concentration specified below for each. ]
Standard solution A:
40 µg/mL of USP Curcuminoids RS in Mobile phase
Standard solution B:
40 µg/mL of USP Curcumin RS in Mobile phase
Standard solution C:
10 µg/mL of USP Desmethoxycurcumin RS in Mobile phase
Standard solution D:
2 µg/mL of USP Bisdesmethoxycurcumin RS in Mobile phase
Sample stock solution:
Transfer about 0.5 g of Powdered Turmeric, accurately weighed, to a 50-mL volumetric flask, add 30 mL of acetone, and sonicate for 30 min. Dilute with acetone to volume, mix, and centrifuge.
Sample solution:
Transfer 5 mL of the Sample stock solution to a 50 mL volumetric flask. Dilute with Mobile phase to volume, and mix.
Chromatographic system
Mode:
LC
Detector:
UV-Vis 420 nm
Column:
4.6-mm × 20-cm; 5-µm packing L1
Flow rate:
1 mL/min
Injection size:
20 µL
System suitability
Sample:
Standard solution A
[NoteThe relative retention times for the curcumin, desmethoxycurcumin, and bisdesmethoxycurcumin peaks are 1.0, 1.2, and 1.4, respectively. ]
Suitability requirements
Chromatogram similarity:
The chromatogram of Standard solution A is similar to the Reference Chromatogram provided with USP Curcuminoids RS.
Resolution:
NLT 2.0, between curcumin and desmethoxycurcumin peaks and the desmethoxycurcumin and bisdesmethoxycurcumin peaks
Tailing factor:
NMT 1.5 for bisdesmethoxycurcumin, desmethoxycurcumin, and curcumin peaks
Relative standard deviation:
NMT 2.0% for desmethoxycurcumin peak, in repeated injections
Analysis
Samples:
Standard solution A, Standard solution B, Standard solution C, Standard solution D, and Sample solution
Calculate the percentage of curcumin, desmethoxycurcumin, and bisdesmethoxycurcumin in the portion of Powdered Turmeric taken:
Result = (rU/rS) × CS × (V/W) × D × 100
Acceptance criteria:
NLT 3% as the sum of curcumin, desmethoxycurcumin, and bisdesmethoxycurcumin
CONTAMINANTS
• Heavy Metals, Method III
• Articles of Botanical Origin, General Method for Pesticide Residues Analysis
• Articles of Botanical Origin, Test for Aflatoxins
• Microbial Enumeration Tests
• Microbiological Procedures for Absence of Specified Microorganisms
SPECIFIC TESTS
• Botanic Characteristics:
It is deep yellow in color, with a characteristic aromatic odor. Under a microscope, Powdered Turmeric reveals thin-walled parenchyma cells containing starch granules, 1530 mm in size, flat or disk shaped, gelatinized or ungelatinized; oil cells full of oil and scattered particles of orange-yellow pigments; prisms of calcium oxalate, usually obscured due to the bright yellow color of the pigment content, detected as bright orange prisms under a polarizing microscope; fragments of spiral vessels and a few reticulate and annular vessels; fragments of epidermal and cork cells; starch granules; scattered unicellular nonglandular trichomes; and the absence of bast fibers.
• Articles of Botanical Origin, Volatile Oil Determination
• Water Determination, Method 1a
• Articles of Botanical Origin, Total Ash
ADDITIONAL REQUIREMENTS
• Packaging and Storage:
Preserve in well-closed containers. Protect from light and moisture, and store at room temperature.
• Labeling:
The label states the Latin binomial and, following the official name, the part of the plant contained in the article.
• USP Reference Standards
USP Bisdesmethoxycurcumin RS
USP Curcumin RS
USP Curcuminoids RS
USP Desmethoxycurcumin RS
Auxiliary Information
Please check for your question in the FAQs before contacting USP.
USP35NF30 Page 1458
Pharmacopeial Forum: Volume No. 33(6) Page 1232
|