Macroscopic— The outer surface of the rhizome is pale to yellowish-brown,crowned with the remains of the aerial stem,and sometimes shows surface annulations up to 15mm in diameter.The roots are pale to yellowish-brown,cylindrical or slightly tapering,sometimes spirally twisted,longitudinally wrinkled and deeply furrowed,up to 4to 10mm in diameter,and pass imperceptibly into rhizome.The short fracture,when dry,becomes tough and pliable on exposure to air.

Microscopic— The rhizomes and roots in transverse section show a thin outer bark separated from a wide xylem by a distinct cambial line.The cork is composed of several rows of thin-walled cells containing yellowish-brown pigment.The rhizome has a small circular pith,occasional small groups of thick-walled,lignified fibers in the pericycle,and a parenchymatous cortex.The phloem and xylem are composed of narrow strands of vascular tissue separated by wide,nonlignified medullary rays.Xylem vessels are lignified,25to 75µm in diameter,usually with reticulate thickening but occasionally with spiral or annular thickening.Sclereids occur singly or in small groups,varying considerably in size and shape from rounded to rectangular to elongated and fiber-like,are up to 300µm long and 20to 40µm wide,with intercellular spaces forming schizogenous oleoresin canals that are 80to 150µm in diameter and contain a dense black deposit present both inside and outside of the central cylinder (unlike Echinacea angustifolia,where the canals are present only outside of the central cylinder).Spherocrystalline masses of inulin occur throughout the parenchymatous tissues.Lignified fibers,present in the periphery of the cortex,are 100to 300µm long and occur singly with phytomelanin often absent (unlike Echinacea angustifolia,where the fibers occur scattered in groups,are 300to 800µm long,and are usually surrounded by phytomelanin).

Change to read:

A:Thin-Layer Chromatographic Identification Test á201ñ—

B:Thin-Layer Chromatographic Identification Test á201ñ—

C: The retention time of the major peak in the chromatogram of the Test solutioncorresponds to that of the echinacoside peak in the chromatogram of Standard solution 1,as obtained in the test for Content of total phenols.The peak area of any peak detected at the locus of 1,3-dicaffeoylquinic acid is not more than 1%of the peak area for the echinacoside peak.USP28

Change to read:

Solvent,Solution A,Solution B,Mobile phase,and Standard solution 2— Prepare as directed for Content of total phenolsunder Echinacea angustifolia.

Standard solution 1— Proceed as directed for Content of total phenolsunder Echinacea angustifolia,except to use USP Powdered Echinacea pallidaExtract RSinstead of USP Powdered Echinacea angustifoliaExtract RS.

Test solution— Proceed as directed for Content of total phenolsunder Echinacea angustifolia,except to use finely powdered Echinacea pallidainstead of Echinacea angustifolia.

Chromatographic system (see Chromatography á621ñ)— Prepare as directed for Content of total phenolsunder Echinacea angustifolia.Chromatograph Standard solution 1,and record the peak responses as directed for Procedure:the chromatogram obtained is similar to the Reference Chromatogram for total phenols provided with USP Powdered Echinacea pallidaExtract RS.Chromatograph Standard solution 2,and record the peak responses as directed for Procedure:the capacity factor,k¢,is not less than 3.0;USP28the tailing factor is not more than 2.0;and the relative standard deviation for replicate injections is not more than 2.5%.

Procedure— Proceed as directed for Content of total phenolsunder Echinacea angustifolia.Separately calculate the percentages of caftaric acid (C13H12O9),chicoric acid (C22H18O12),chlorogenic acid (C16H18O9),and echinacoside (C35H46O20)in the portion of Echinacea pallidataken by the formula: in which Fis the response factor and is equal to 0.695for chicoric acid,0.881for caftaric acid,1.000for chlorogenic acid,and 2.220for echinacoside;Cis the concentration,in mg per mL,of USP Chlorogenic Acid RSin Standard solution 2;Wis the weight,in mg,of Echinacea pallidataken;and riand rSare the peak responses for the relevant analyte obtained from the Test solutionand Standard solution 2,respectively.Calculate the percentage of total phenols in the portion of Echinacea pallidataken by adding the individual percentages calculated.