Rhodiola crenulata Root and Rhizome

Rhodiola crenulata Root and Rhizome

Final Authorized Version 1.0

Rhodiola crenulata Root and Rhizome

 


 

DEFINITION

The article consists of the dried roots and rhizomes of Rhodiola crenulata (Hook.f. & Thomson) H. Ohba, currently accepted name Sedum crenulatum Hook.f & Thomson(Family Crassulaceae), collected after the scape wither in autumn. It contains NLT 1.0% of total phenylethanoids calculated as the sum of salidroside (C14H20O7) and tyrosol (C8H10O2) on the dried basis; and NLT 0.6% of salidroside on the dried basis.

 

SYNONYMS

Rhodiola euryphylla (Fröd.) S.H.Fu

Rhodiola megalophylla (Fröd.) S.H.Fu

Rhodiola rotundata (Hemsl.) S.H.Fu

Sedum euryphyllum Fröd.

Sedum megalanthum Fröd.

Sedum megalophyllum Fröd.

Sedum rotundatum Hemsl.

 

POTENTIAL CONFOUNDING MATERIALS

Rhodiola calliantha (H. Ohba) H. Ohba

Rhodiola cretinii (Hamet) H. Ohba

Rhodiola dumulosa (Franch.) S. H. Fu

Rhodiola heterodonta (HK. f. et Thoms.) A. Bor.

Rhodiola kirilowii (Regel) Maxim.

Rhodiola linearifolia A. Bor.

Rhodiola quadrifida (Pall.) Fisch. et Mey.

Rhodiola robusta (Praeg.) S. H. Fu

Rhodiola rosea L.

Rhodiola sachalinensis A. Bor.

Rhodiola serrata H. Ohba

 

SELECTED COMMON NAMES

Chinese: 大花红景天 (Da Hua Hong Jing Tian)

English: Rhodiola crenulata

 

CONSTITUENTS OF INTEREST

Phenylethanoids: Salidroside and tyrosol

Benzoic acid: Gallic acid

 

IDENTIFICATION

• A. Botanical Characteristics

Macroscopic: Rhizome cylindrical, stout, slightly curved, few branched, 5–20 cm long, 3–5 cm in diameter. Externally brown or chocolate brown, coarse with wrinkles; under the outer epidermis, a layer of yellow membranous epidermis with pink decorative pattern appears; some old scape persist with triangular or ovate membranous scales at the base; internode irregular, fracture pink to purplish-red with a ring; texture light and lax. Taproot cylindrical, stout, about 20 cm long, and about 1.5 cm in diameter at the upper part. Lateral root 10–30 cm long, fracture orange-red or purplish-red, sometimes with cracks.

Microscopic

Transverse section of root: Cork consists of 5–8 layers of cells; phelloderm cells are elliptic or sub-rounded. Stele is broad with numerous vascular bundles in 2–4 rings, peripheral vascular bundles of collateral type are relatively large, interior 2–3 rings of amphivasal-type vascular bundles are gradually smaller toward inside.

Transverse section of rhizome: The old rhizomes contain 2–3 bands of cork. The young rhizomes do not contain cork layer. Cork consists of several layers of cells and phelloderm is indistinct. Stele collateral vascular bundles are radially arranged in a ring. The outer and inner vascular tissues of each bundle are well-developed, parenchymatous cells in the middle, phloem and xylem are almost equal with obvious cambium. Medulla is broad, consists of parenchymatous cells with amphivasal vascular bundles randomly. The parenchymatous cells contain brown secretion.

• B. HPTLC for Articles of Botanical Origin <203>.)

Standard solution: 2.0 mg/mL of USP Salidroside RS and 1.0 mg/mL of USP Rosavin RS in methanol

Sample solution: Sonicate 0.5 g of Rhodiola crenulata Root and Rhizome, finely powdered, in 5 mL of methanol for 10 min, centrifuge, and use the supernatant.

Chromatographic system

Adsorbent: Chromatographic silica gel with an average particle size of about 5 µm

Application volume: 5 µL, as 8-mm bands

Relative humidity: Condition the plate to a relative humidity of about 33% using a suitable device.

Developing solvent system: Ethyl acetate, methanol, water, and formic acid (77:13:10:2)

Developing distance: 6 cm

Derivatization reagent: Dissolve 1 g of diphenylamine in 40 mL of acetone, add 1 mL of anilline, and mix. Carefully add 7.5 mL of phosphoric acid, and mix.

Analysis

Samples: Standard solution and Sample solution

Apply the Samples as bands and dry in air. Develop in a saturated chamber, remove the plate from the chamber, and dry in air. Treat with Derivatization reagent, heat at 120º for 5 min, and examine under visible light.

System suitability: The Standard solution shows two gray bands at the lower half of the chromatogram. The band with a higher RF is due to salidroside, and the band with a lower RF is due to rosavin.

Acceptance criteria: The Sample solution exhibits a grey band corresponding in RF  and color to the salidroside in the Standard solution. In the Sample solution, no band corresponding in RF  and color to the rosavin in the Standard solution is observed (a distinction from Rhodiola rosea Root and Rhizome). The Sample solution exhibits additional bands, including two gray bands between salidroside and rosavin, two yellow bands in the upper half part, and a couple of gray bands close to the starting position.

• C. HPLC

Analysis: Proceed as directed in the Assay for Content of Phenylethanoids.

Acceptance criteria: The Sample solution exhibits a peak with a retention time corresponding to salidroside in the Standard solution, a peak due to tyrosol with lower intensity than  salidroside, and a peak due to gallic acid. The content ratio of salidroside to tyrosol is not lower than 2.

 

ASSAY

• Content of Phenylethanoids

Solution A: 0.02% Phosphoric acid in water

Solution B: Methanol and acetonitrile (9:1)

Mobile phase: See Table 1.

 

Table 1

Time
(min)

Solution A
(%)

Solution B
(%)

0

95

5

10

95

5

15

83

17

28

83

17

28.1

10

90

43

10

90

43.1

95

5

53

95

5

 

Solvent: Methanol and water (6:4)

Standard solution: 0.30 mg/mL of USP Salidroside RS in methanol

Sample solution: Accurately transfer about 500 mg of Rhodiola crenulata Root and Rhizome, finely powdered, to a suitable stoppered conical flask and accurately add 15.0 mL of Solvent. Weigh the filled flask with a precision of ±0.1 mg, stopper, and sonicate for 30 min. Cool to room temperature and adjust to the initial weight by adding Solvent if needed. Before injection, pass through a membrane filter of 0.45-μm or finer pore size, and discard the first portion of the filtrate.

Chromatographic system

(See Chromatography <621>, System Suitability.)

Mode: LC

Detector: UV 275 nm

Column: 4.6-mm × 25-cm; 5-μm packing L1 (similar to Merck Purospher STAR RP-18 endcapped)

Column temperature: 25°

Flow rate: 1.0 mL/min

Injection volume: 10 µL

System suitability

Samples: Standard solution and Sample solution

Suitability requirements

Resolution: NLT 1.5 between the salidroside and tyrosol peaks, Sample solution

Tailing factor: NMT 1.5 for the salidroside peak, Standard solution

Relative standard deviation: NMT 2.0% for the salidroside peak, Standard solution

Analysis

Samples: Standard solution and Sample solution

Using the chromatogram of the Standard solution and the relative retention times, identify the retention times of the peaks corresponding to gallic acid, salidroside, and tyrosol in the Sample solution. [Note—The approximate relative retention times for the peaks of gallic acid, salidroside, and tyrosol are 0.48, 1.00, and 1.05, respectively.]

Separately calculate the percentages of salidroside and tyrosol in the portion of Rhodiola crenulata Root and Rhizome taken:

 

Result = (rU/rS) × CS × (V/W) × F × 100

 

rU   = peak area of the relevant analyte from the Sample solution

rS   = peak area of salidroside from the Standard solution

C = concentration of USP Salidroside RS in the Standard solution (mg/mL)

V    = volume of the Sample solution (mL)

W   = weight of Rhodiola crenulata Root and Rhizome taken to prepare the Sample solution (mg)

F    = conversion factors for the analytes; 1.00 for salidroside, 0.43 for tyrosol

 

Calculate the content of total phenylethanoids as the sum of the percentages of salidroside and tyrosol.

Acceptance criteria

Salidroside: NLT 0.6% on the dried basis

Total phenylethanoids: NLT 1.0% on the dried basis

 

CONTAMINANTS

Articles of Botanical Origin <561>, Limits of Elemental Impurities: Meets the requirements

Articles of Botanical Origin <561>, Pesticide Residue Analysis: Meets the requirements

Microbial Enumeration Tests <61>: The total aerobic bacterial count does not exceed 105 cfu/g, the total combined molds and yeasts count does not exceed 103 cfu/g, and the bile-tolerant Gram-negative bacteria count does not exceed 103 cfu/g.

Tests for Specified Microorganisms <62>: Meets the requirements of the tests for the absence of Salmonella species and Escherichia coli

Articles of Botanical Origin <561>, Test for Aflatoxins: Meets the requirements

 

SPECIFIC TESTS

Articles of Botanical Origin <561>, Methods of AnalysisForeign Organic Matter: NMT 2.0%

Articles of Botanical Origin <561>, Methods of AnalysisAlcohol-Soluble Extractives, Method 1: NLT 25.0%

• Loss on Drying <731>: NMT 12.0%

Articles of Botanical Origin <561>, Methods of AnalysisTotal Ash: NMT 6.0%

Articles of Botanical Origin <561>, Methods of AnalysisAcid-Insoluble Ash: NMT 1.0%

 

ADDITIONAL REQUIREMENTS

• Packaging and Storage: Preserve in well-closed containers, protected from light and moisture, and store at controlled room temperature.

• Labeling: The label states the Latin binomial following the official name of the plant contained in the article.

USP Reference Standards <11>

USP Rosavin RS

USP Salidroside RS

 

 

Other Versions

Proposed For Comment Version 0.2
Proposed For Development Version 0.1