ABSTRACT
OBJECTIVE：To establish the method for content dete rmination of polyphyllin Ⅱ，Ⅵ，Ⅶ in Ypsilandra thibetica ， and to compare the differences of 3 saponins in different parts of Y. thibetica from different producing areas. METHODS ：HPLC method was adopted to determine the contents of polyphyllin Ⅱ，Ⅵ，Ⅶ in whole grass part and underground part of Y. thibetica from 10 producing areas. The determination was performed on Kromasil C 18column with mobile phase consisted of acetonirile-water （gradient elution ）at the flow rate of 1.0 mL/min. The column temperature was 35 ℃，and detection wavelength was set at 203 nm；sample size was 10 μL. With the contents of 3 saponins as the index ，20 batches of Y. thibetica were analyzed by cluster analysis and PLS-DA analysis ；the aggregation of samples was analyzed and determined the primary difference components. RESULTS：The linear range of polyphyllin Ⅱ，polyphyllin Ⅵ and polyphyllin Ⅶ were 0.051-2.04，0.007-0.28，0.168-6.72 μg， respectively（r≥0.999 5）；the detection limits were 1.92，1.75，1.87 ng，respectively；and the quantitative limits were 6.40，5.87， 6.23 ng，respectively；RSD of precision ，reproducibility and stability tests （24 h）were all lower than 2％（n＝6）；the average recovery rates were 99.29％，101.38％ and 99.64％，with RSDs of 1.17％，2.64％，0.75％（n＝6），respectively. The content of polyphyllin Ⅱ was 0.615-1.875 mg/g，that of polyphyllin Ⅵ was 0-0.095 mg/g，and that of polyphyllin Ⅶ was 3.158-12.354 mg/g. Cluster analysis showed that 20 batches of samples were clustered into two groups ，batch S 9-S12 were clustered in to one group，and the other 16 batches of samples were clustered into another group. PLS-DA analysis showed that 20 batches of samples were divided into 3 areas，batch S 1，S2，S8，S14，S16，S20 were included in area Ⅰ；batch S 9-S12 included in area Ⅱ；and the rest of the samples included in area Ⅲ. The quality of Y. thibetica from different habitats was different ，and there was no difference in the saponin composition between the whole grass and the underground part. Weight ranking found that mail：cscdtcm@126.com polyphyllin Ⅶ was the main difference component in Y. thibetica，and the content of polyphyllin Ⅶ in Y. thibetica from Pengzhou city and Dayi county was the highest. CONCLUSIONS ：The established method is simple ，convenient and sensitive. It can be used for the content determination of 3 saponins in Y. thibetica . The content of active components is higher and the quality is better in Y. thibetica from Pengzhou city and Dayi county.
ABSTRACT
Objective: To combine macroscopical characteristic indices and chemical indices of Andrographis Herba to evaluate its quality grade. Methods: Both macroscopical characteristic indices and chemical indices (the content of four active diterpenoids and the content of ethanol-soluble extractives) of different batches of Andrographis Herba were determined. The macroscopical characteristic indices were encoded using the method of numerical taxonomy, and the content of four active diterpenoids were determined by HPLC. To screen out the appropriate indices for classification, the correlational analyses were conducted between encoded macroscopical characteristic indices and chemical indices. The quality grade was made by principal component clustering analysis according these evaluation indices, and then was analyzed through partial least squares discriminant analysis (PLS-DA). Furthermore, a partial least squares (PLS) regression was constructed for the quality grade prediction of Andrographis Herba. Results: It showed that the samples could be divided into three grades according to the principal component clustering analysis, and was reasonable evaluating by PLS-DA. The PLS regression model for quality grade of Andrographis Herba was constructed as follows: grade Y=3.761-0.020×the leaf content-0.388×the content of andrographolide-1.117×the content of neoandrographolide-0.274×the content of deoxyandrographolide-0.287×the content of 14-deoxy-11,12-didehydro-andrographolide-0.302×the content of four active diterpenoids-0.104×the content of ethanol-soluble extractives-0.015×the color of stem-0.008 4×the color of leaf-0.003×the diameter of base part of stem+0.020×the number of branch+0.137×the diameter of the upper stem+0.011×plant height, if Y=0.7-1.3, the predicted quality was grade A, if Y=1.7-2.3, then B grade, and if Y=2.7-3.3, C grade or qualified product. Conclusion: The model of grade evaluation we constructed using principal component clustering analysis combing with PLS regression analysis performed well, which was applicable in evaluating the quality grade of Andrographis Herba and other traditional Chinese medicines. It also provided a new strategy for study on grade standards of traditional Chinese medicines.