Native Guggul Extract
Native Guggul Extract is prepared from Guggul, using ethyl acetate, alcohol, or methanol. The ratio of starting crude plant material to Native Extract is approximately 9:1. It contains NLT 5.0% of guggulsterones E and Z, calculated on the anhydrous basis as guggulsterone Z. It does not contain added substances.
• A. Thin-Layer Chromatographic Identification Test
Standard solution: 10 mg/mL of USP Purified Guggul Extract RS, with heating, in acetonitrile
Sample solution: Homogenize Native Guggul Extract by heating in a water bath at 6080. Prepare a 5-mg/mL solution in acetonitrile with heating.
Developing solvent system: A mixture of hexane and ethyl acetate (6:4)
Adsorbent: 0.25-mm layer of chromatographic silica gel mixture, typically 20 cm in length
Application volume: 10 µL
Samples: Standard solution and Sample solution
Apply the Samples as bands to a suitable plate. Use a saturated chamber. Develop until the solvent front has moved about about three-fourths the length of the plate, dry the plate, and examine under UV light at 254 nm.
Acceptance criteria: The chromatogram of the Sample solution exhibits bands at RF values of about 0.38 and 0.47, due to guggulsterone E and Z, respectively. Both bands correspond in RF to bands in the chromatogram from the Standard solution.
• B. HPLC Identification Test
Analysis: Proceed as directed in the test for Content of Guggulsterones E and Z.
Acceptance criteria: The chromatogram of the Sample solution exhibits peaks for guggulsterones E and Z at retention times that correspond to those of Standard solution A.
• Content of Guggulsterones E and Z
Mobile phase: A mixture of acetonitrile and water (45:55)
Standard solution A: 10 mg/mL of USP Purified Guggul Extract RS, with heating, in acetonitrile. Pass the solution through a filter of 0.45-µm pore size before injection.
Standard solution B: 0.1 mg/mL of USP Guggulsterone Z RS in acetonitrile. Pass the solution through a filter of 0.45-µm pore size before injection.
Sample solution: Homogenize the Native Guggul Extract by heating in a water bath at 6080. Dissolve a weighed quantity of homogenized Native Extract, with heating, in acetonitrile to obtain a solution having a known concentration of about 0.2 mg/mL of guggulsterones E and Z. Pass through a filter of 0.45-µm pore size before injection.
Detector: UV 242 nm
Column: 4.6-mm × 25-cm; 5-µm packing L1
Flow rate: 2.0 mL/min
Injection size: 20 µL
Column temperature: 27 ± 1
Samples: Standard solution A and Standard solution B [NoteThe relative retention times for guggulsterones E and Z are about 0.69 and 1.0, respectively. ]
Chromatogram similarity: The chromatogram from Standard solution A is similar to the reference chromatogram provided with the lot of USP Purified Guggul Extract RS being used.
Resolution: NLT 2.0 between the guggulsterone Z peak and the peak before, Standard solution A
Tailing factor: NMT 1.5 for the guggulsterone Z peak, Standard solution B
Relative standard deviation: NMT 2.0% for the guggulsterone Z peak (replicate injections), Standard solution B
Samples: Standard solution A, Standard solution B, and Sample solution
Allow Standard solution A to elute for NLT two times the retention time of guggulsterone Z, as determined in Standard solution B. Using the chromatogram of Standard solution A and the reference chromatogram provided with the lot of USP Purified Guggul Extract RS being used, identify the retention times of the peaks corresponding to guggulsterone E and guggulsterone Z.
Calculate the percentage of guggulsterones E and Z as guggulsterone Z in the portion of Native Guggul Extract taken:
Result = (rU/rS) × Cs × (V/W) × 100
Acceptance criteria: NLT 5.0% of guggulsterones E and Z, calculated as guggulsterone Z, on the anhydrous basis
• Heavy Metals, Method II 231: NMT 20 µg/g
• Articles of Botanical Origin, General Method for Pesticide Residues Analysis 561: Meets the requirements
• Botanical Extracts, Residual Solvents 565: Meets the requirements
• Microbial Enumeration Tests 2021: The total aerobic microbial count does not exceed 104 cfu/g, and the total combined yeasts and molds 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.
• Water Determination, Method 1a 921: NMT 5.0%
• Packaging and Storage: Preserve in well-closed containers, protected from light and moisture, and store in a cool place.
• Labeling: The label states the Latin binomial and, following the official name, the part of the plant from which the article was derived. It meets other labeling requirements under Botanical Extracts 565.
• USP Reference Standards 11
USP Guggulsterone Z RS
USP Purified Guggul Extract RS
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USP35NF30 Page 1351Pharmacopeial Forum: Volume No. 34(4) Page 1002