Analysis of Quality of Dong Medicine Sikuaiwa from Different Origins by High Performance Liquid Chromatography Fingerprint Combined with Chemometrics

1 g of Sikuaiwa powder was taken and placed in the round bottom flask, and 50 mL of 75% (volume fraction, the same below) methanol solution was added. The mixture was reflux extracted for 1 h and filtered. The filtrate was made its volume up to 50 mL with 75% methanol solution, and passed through 0.45 μm organic filter membrane. The test solution of Sikuaiwa was separated on Agela Promosil C₁₈ column, using the mixed solution composed of 0.2% (volume fraction) formic acid solution and acetonitrile at different volume ratios as mobile phase for gradient elution at 35 ℃ of column temperature. The components of the test solution were detected at wavelength of 290 nm, and the chromatogram was recorded. High performance liquid chromatography (HPLC) fingerprint of Sikuaiwa was established according to the Similarity Evaluation System for Chromatographic Fingerprint of Traditional Chinese Medicine (2004 Edition). The principal component analysis and partial least-square discriminant analysis were carried out by IBM SPSS Statistics 25.0 software and SIMCA software(12.0 Edition). As shown by the results, there were 14 common peaks in the fingerprints of 11 batches of Sikuaiwa. Compared with the oleanolic acid reference substance, the compound of peak 12 was confirmed to be oleanolic acid, and the similarity was in the range of 0.833-0.979 between fingerprints of 11 batches of Sikuaiwa and reference fingerprint. Three principal components were obtained by principal component analysis, and the cumulative variance contribution rate reached 92.258%. The 8 differential markers that affected the quality of Sikuaiwa from different origins were screened out by partial least-square discriminant analysis.