Study On The Method Of Quality Assessment Of Eclipta Prostrata L.

Eclipta prostrata L. is one of the traditional Chinese medicines(TCM). 19 Eclipta prostrata L. samples were collected from different areas and the method of quality assessment was developed.Wedelolactone which is one of the effective constituents of Eclipta prostrata L. was isolated and identified by UV, IR, MS, ¹H-NMR and ¹³C-NMR spectroscopy. A reversed-phase HPLC method was developed for determination of wedelolactone, chromatographic condition was: a Batesil C18 column(250 mm×4.6mm, 5μm), a mobile phase of methol-acetonitrile-water(35:15:50, v/v/v, pH3.6), wavelength of 249 nm and column temperature of 30℃. As a result, a good linearity was obtained from 2.64～88.0μg/mL with r=0.9996 for wedelolactone. The average recovery rate was 96.1% with RSD1.8%(n=9). A another reversed-phase HPLC method was also developed for determination of protocatechuic acid, chromatographic condition was: a Batesil C18 column(250 mm×4.6mm, 5μm), a mobile phase of methol-water-aectic acid(25:75:0.20, v/v/v), wavelength of 260 nm and column temperature of room temperature. As a result, a good linearity was obtained from 0.24～9.6μg/mL with r=0.9999 for protocatechuic acid. The average recovery rate was 100.2% with RSD1.8%(n=9). Based on the two methods, the wedelolactone and protocatechuic acid content in Eclipta prostrata L. from fifteen different areas were determined respectively. The analytical methods were proved to be sensitive, quick, simple, and accurate for quantity determination of wedelolactone and protocatechuic acid with good repeatability, reproducibility, and stability. The recovery rate and the linear correlation are perfect. The RP-HPLC methods are reliable andrecommendable for the quality control of Eclipta prostrata L. In this paper, HPLC with Batesil C18 column(250 mm×4.6mm, 5μm) was used, phosphate acid-water( 1:99) and phosphate acid-acetonitrile(1:99) as mobile phase A and B gradient elution and detection wavelength of 330 nm to analyze 19 Eclipta prostrata L. samples from different areas. The HPLC chromatographic fingerprints of Eclipta prostrata L. showing 22 peaks was established from 19 Eclipta prostrata L. samples and studied by chemical pattem recognition methods. Hierarchical cluster analysis and similarity analysis were adopted to analyze data of HPLC fingerprints of Eclipta prostrata L.. The Eclipta prostrata L. samples were divided into two grades, the first grade and the second grades. According the result of classification, the similarity analysis method for quality assessment of Eclipta prostrata L. samples was developed. The similarity was determi.ned by cosine or correlation. The similarity of the first grade was 0.80～1.00, the second grade was less than 0.80.The result of similarity analysis was the same as that of hierarchical duster analysis. The trend was consistent with two different similarities testing the fingerprints of Eclipta prostrata L.. The HPLC chromatographic fingerprints similarity analysis method can be used to control the quality of Eclipta prostrata L. effectively. When unknown samples are analyzed by this method, identification, classification and assessment can be carried out by compared the similarity and wedelolactone content of standard samples with unknown ones.