Chamomile consists of the dried flower heads of Matricaria recutita L. (Matricaria chamomilla L., Matricaria chamomilla L. var. courrantiana, Chamomilla recutita L.) Rauschert (Fam. Asteraceae alt. Compositae). It contains NLT 0.4% of blue volatile oil, NLT 0.3% of apigenin-7-glucoside, and NLT 0.15% of bisabolol derivatives, calculated as levomenol.
•  A. Thin-Layer Chromatographic Identification Test
Standard solution:  1.0 mg/mL of borneol, 2.0 mg/mL of bornyl acetate, and 0.4 mg/mL of guaiazulene in toluene
Sample solution:  Reduce 1.0 g of Chamomile to a coarse powder, using a porcelain pestle and mortar. Transfer to a 1.5-cm × 15-cm chromatographic column, and tamp lightly with a short length of rubber hose. Rinse the pestle and mortar twice, each time with 10 mL of methylene chloride. Pour the rinsings into the column. Collect the percolate in a flask with a long, narrow neck, and remove the solvent by evaporation on a water bath. Dissolve the residue in 0.5 mL of toluene.
Adsorbent:  0.25-mm layer of chromatographic silica gel
Developing solvent:  Chloroform
Spray reagent:  Mix anisaldehyde, glacial acetic acid, and methanol (0.5: 10: 85). Then carefully add 5 mL of sulfuric acid to this solution.
Application volume:  10 µL, as 3-mm × 20-mm bands
Samples:  Standard solution and Sample solution
Examine the plate under short-wavelength UV light: the Sample solution exhibits a number of quenching areas, the largest of which is due to en-yne-dicycloether and has the same RF value as the band due to bornyl acetate in the Standard solution. There is also a band due to matricin near the line of application. Spray the plate evenly with the Spray reagent. Examine the plate in daylight while heating at 100–105 for 5–10 min. The chromatogram obtained from the Standard solution shows in the lower third a brownish yellow zone that becomes violet-gray after a few hours and is due to borneol; in the middle a yellowish brown to gray zone due to bornyl acetate; and in the upper third a deep red zone with a blue edge due to guaiazulene.
Acceptance criteria:  The Sample solution exhibits a blue zone due to matricin near the starting point; several violet-red zones, one of which is due to bisabolol, at RF values between those of borneol and bornyl acetate; a brownish zone, due to en-yne-dicycloether, at an RF value corresponding to that of bornyl acetate; red zones, due to terpenes, at RF values similar to those of guaiazulene; and other zones that appear in the middle and lower parts of the chromatogram.
•  B.
Analysis:  Dissolve 0.25 g of dimethylaminobenzaldehyde in a mixture of 5 mL of phosphoric acid, 45 mL of acetic acid, and 45 mL of water. Transfer 2.5 mL of this solution and 0.1 mL of the Sample solution, prepared as directed for Identification test A, to a test tube. Heat on a water bath for 2 min, and allow to cool. Add 5 mL of solvent hexane, and shake.
Acceptance criteria:  The aqueous layer has a distinct greenish blue or blue color.
•  Content of Apigenin-7-glucoside
Dilute phosphoric acid:  Mix 5.0 mL of phosphoric acid in 50 mL of water. Dilute with water to 100 mL.
Solution A:  0.005 M solution of monobasic potassium phosphate. Adjust with Dilute phosphoric acid to a pH of 2.55 ± 0.05.
Solution B:  Acetonitrile and methanol (13:7)
Mobile phase:  See Table 1.
Table 1
Solution A
Solution B
0 74 26
3 74 26
22 15 85
27 74 26
30 74 26
Standard solution:  25.0 µg/mL of USP Apigenin-7-glucoside RS and 10.0 µg/mL of 7-methoxycoumarin in methanol and water (1:1)
Sample solution:  Transfer 1.0 g of Chamomile to a suitable flask fitted with a reflux condenser and a stirrer. Add 80.0 mL of methanol, and reflux the mixture with stirring for 1 h. Cool the flask to room temperature, pass the extract through a folded filter paper, and collect the filtrate in a 100-mL volumetric flask. Rinse the flask with 3 mL of methanol, pour the methanolic rinsings through the filter paper, and add the filtrate to the volumetric flask. Dilute with methanol to volume, and filter. Transfer 25.0 mL of the filtered solution to a round-bottom flask fitted with a reflux condenser and a stirrer; add 5.0 mL of sodium hydroxide solution, prepared by dissolving 0.4 g of sodium hydroxide in 5.0 mL of water; and reflux the mixture for 25 min. Cool the flask, and adjust the solution with hydrochloric acid to a pH of 5.0–6.2. Quantitatively transfer the solution to a 50-mL volumetric flask, dilute with methanol to volume, and filter, discarding the first 10 mL of the filtrate.
Chromatographic system 
Mode:  LC
Detector:  UV 335 nm
Column:  4-mm × 12.5-cm; packing L1
Flow rate:  1 mL/min
[Note—Make adjustments, if necessary, to obtain relative retention times of 0.63 for apigenin-7-glucoside and 1.0 for 7-methoxycoumarin. ]
Injection size:  15 µL
System suitability 
Sample:  Standard solution
[Note—The relative retention times for apigenin-7-glucoside, 7-methoxycoumarin, apigenin, trans-spiroether, and cis-spiroether are about 0.63, 1.0, 1.2, 1.6, and 1.8, respectively. ]
Suitability requirements 
Resolution:  NLT 3.5 between apigenin-7-glucoside and 7-methoxycoumarin
Relative standard deviation:  NMT 2.0% for apigenin-7-glucoside
Samples:  Standard solution and Sample solution
[Note—Allow the Sample solution to elute for NLT 6 times the retention time of apigenin-7-glucoside. ]
Calculate the percentage of apigenin-7-glucoside in the portion of Chamomile taken:
Result = (rU/rS) × CS × (V/W) × 100
rU== peak response of apigenin-7-glucoside from the Sample solution
rS== peak response of apigenin-7-glucoside from the Standard solution
CS== concentration of USP Apigenin-7-glucoside RS in the Standard solution (mg/mL)
V== volume of Sample solution (mL)
W== weight of Chamomile taken to prepare the Sample solution (mg)
Acceptance criteria:  NLT 0.3%
•  Content of Bisabolane Derivatives
Standard solution:  1 mg/mL of USP Levomenol RS in cyclohexane
Sample solution:  Transfer the volatile oils obtained in the test for Articles of Botanical Origin 561, Volatile Oil Determination to a 25-mL volumetric flask, rinse the graduated tube of the apparatus with a small portion of cyclohexane, transfer the rinsing to the 25-mL volumetric flask, add cyclohexane to volume, and mix.
Chromatographic system 
Mode:  GC
Detector:  Flame ionization
Column:  0.32-mm × 30-m fused-silica capillary; coated with a 0.25-µm film of phase G16
Column:  See Table 2.
Table 2
Hold Time
at Final
70 4 230 10
Detector:  250
Injection port:  220
Carrier gas:  Helium
Flow rate:  1.0 mL/min
Injection size:  1 µL
System suitability 
Sample:  Standard solution
Suitability requirements 
Tailing factor:  NMT 1.8 for levomenol
Relative standard deviation:  NMT 2.0%
Samples:  Standard solution and Sample solution
Measure the peak areas. Identify the peaks due to levomenol, bisabolol oxide B, bisabolol oxide, and bisabolol oxide A in the Sample solution, using the retention time of levomenol in the Standard solution and the approximate relative retention times of 0.89, 0.97, and 1.1 for bisabol oxide B, bisabol oxide, and bisabol oxide A, respectively, with reference to the levomenol peak.
Calculate the percentage of bisabolane derivatives in the portion of Chamomile taken:
Result = (rT/rS) × CS × (V/W) × 100
rT== sum of the peak areas for bisabolol oxide B, bisabolol oxide, levomenol, and bisabolol oxide A from the Sample solution
rS== levomenol peak area from the Standard solution
CS== concentration of USP Levomenol RS in the Standard solution (mg/mL)
V== volume of Sample solution (mL)
W== weight of Chamomile taken to prepare the Sample solution (mg)
Acceptance criteria:  NLT 0.15%
•  Articles of Botanical Origin, Volatile Oil Determination 561
Analysis:  Proceed as directed, except use 60 g of coarsely powdered Chamomile as the test specimen, a 2-L round-bottom flask, 300 mL of water as distillation liquid, and 0.5 mL of xylene in the graduated tube. Distill for 4 h at a rate of 3–4 mL/min.
Acceptance criteria:  NLT 0.4% of blue volatile oil is found. [Note—Retain the volatile oils for use in the test for Content of Bisabolol Derivatives. ]
•  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, and the bile-tolerant Gram-negative bacterial 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:  Flower head is hemispherical, about 6 mm in diameter, composed of a few ray florets and numerous disk florets (distinction from Matricaria discoidea, which has disk florets only), carried on a receptacle surrounded by an involucre. Involucre is green, formed of two to three rows of lanceolate, glabrous, and imbricated bracts with blunt apices and scarious whitish edges. Ray florets, which usually have fallen off, have 10–20 pistils; corolla is ligulate, white, but darkens at a length of 6 mm and a width of about 2 mm, 3-toothed, and traversed by four main veins. Disk florets are yellow, perfect, about 2 mm in length; corolla is tubular with five teeth; five stamens are epipetalous and syngenesious. Receptacle is hollow (distinction from Chrysanthemum and Anthemis species), hemispherical in the young and conical in the old flower head, 3–10 mm in width, and lacking paleae. Achene is ovoid, and has three to five longitudinal ribs.
Microscopic:  Separate the capitulum into its parts, and examine under a microscope. The outer, abaxial epidermis of the involucral bracts shows a scarious margin with a single layer of radially elongated cells and a central part made up of chlorophyll tissue covered by elongated epidermal cells with sinuous lateral walls, stomata, and secretory trichomes. The vascular bundles are surrounded by numerous elongated, pitted sclereids with fairly large lumens. In surface view, ligulate and tubular corollas show isodiametric or elongated cells with more or less wavy walls and a few glandular trichomes. The outer part of the epidermis of the ligulate florets consists of papillary cells with cuticular striations radiating from their tips. In the mesophyll, very small clusters of calcium oxalate are sometimes seen. Four main veins run lengthwise through the entire mesophyll, sometimes accompanied by one or two other veins, which are shorter and run parallel to the main veins. Each of the two main median veins split into two near the tip and, with the lateral veins, anastomose two by two to form three arcs at the three terminal teeth of the ligule. The ovaries, oval to spherical, of both kinds of florets have at their base a sclerous ring consisting of a single row of cells. The epidermis of the ovary is made up of elongated cells with sinuous walls between which secretory trichomes are situated. The ovaries contain numerous, very small clusters of calcium oxalate. In the tubular florets, the low part of each stamen filament is surrounded by thick-walled cells. The ends of the two stigmata have papillose epidermal cells. The pollen grains have a diameter of about 30 µm and are rounded and triangular, with three germinal pores and a spiny exine.
•  Broken Flowers: NMT 25% passes through a No. 25 standard-mesh sieve (see Particle Size Distribution Estimation by Analytical Sieving 786).
•  Articles of Botanical Origin, Total Ash 561: NMT 13.0%, determined on 1.0 g of powdered Chamomile
•  Packaging and Storage: Preserve in well-closed containers, protected from light.
Change to read:
•  Labeling: The label states the Latin binomial 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 Apigenin-7-glucoside RS
USP Levomenol RS
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