[Fingerprint of Curcuma phaeocaulis by LC-MS]

To study and establish the fingerprint of Curcuma phaeocaulis by high performance liquid chromatography-mass spectrometry.

LC-MS analysis was carried out in a Hewlett Packard model 1100 liquid chromatograph coupled with electrospray mass spectrometry. The analysis was performed on a ZORBAX RX-C18 column (4.6 mm x 250 mm, 5 microm) with a mobile phase of methanol-isopropanol-water (mathanoic acid 0.4%) in a gradient mode at a flow rate of 1.0 mL min(-1), and the column temperature of 35 degrees C. The wavelength of the UV detector was set at 254 nm. RSD values of precision, repeatability and stability of this LC-MS method were less than 5%. The total 10 batches of C. phaeocaulis from the different places of Sichuan province were detected, and different commodities and preparative methods were compared.

The standard fingerprint of the extract of C. phaeocaulis, which collected in the different places of Sichuan province, was originated from the Similarity Evaluation System for Chromatographic Fingerprint of TCM 2004' software, and 15 common peaks existed in the fingerprint. Each peak in the fingerprint was separated well under the above analysis condition and similarities of the extracts of C. phaeocaulis samples of the ten batches were all above 0.90. By comparison of the retention time and the on-line UV spectra and their molecular weights of the chemical standards, peaks 4-6 and 9 were identified as curcumin (4), demethoxycurcumin (5), curcumenol (6), and curcumone (9), respectively.

This LC-MS fingerprint and quantitative assessment can be used in the quality control of C. phaeocaulis.