Analyses and identification of the chemical constituents of the Uighur formulation Baixuan Xiatare using three-stage infrared spectroscopy

OBJECTIVE:To identify,rapidly and accurately,the chemical composition of the traditional Uighur formulation Baixuan Xiatare(BXXTR-FU).METHODS:We investigated if application of three-stage infrared(IR)spectroscopy enabled identification of the main chemical constituents(and their origins)in BXXTR-FU.RESULTS:The characteristic peaks of herbal material(s)and BXXTR-FU were assigned.In Fourier transform-IR(FT-IR)spectroscopy of BXXTR-FU,peaks at1616 and 1605 cm-1 of BXXTR-FU were considered to denote anthraquinones and their derivatives;1066 cm-1 was regarded as the characteristic absorption peak of resin glycosides.In second-derivative IR(SD-IR)spectroscopy,the main carbonyl types of BXXTR-FU in the range 1743-1636 cm-1 were assigned:1651 cm-1 belonged to the carbonyl stretching vibrations of flavonoids and chromones;1717 cm-1 belonged to tannins;1699 cm-1 belonged to carboxylic acids;1636 cm-1 belonged to anthraquinones and their derivatives.SD-IR spectroscopy further confirmed that the characteristicabsorption peaks at 1636,1618 and 1603 cm-1 could be used as markers that BXXTR-FU contained anthraquinones and their derivatives.Synchronous2 D-IR correlation spectra of chemical groups further confirmed the results of FT-IR and SD-IR spectroscopy.CONCLUSION:Our study strongly supported the necessity and importance of three-stage IR spectroscopy owing to its rapid and accurate identification of herbal formulations.