Infrared fingerprint analysis of hippocampus's ethanol extracts coupled with cluster analysis, principal component analysis and discriminant analysis / 中国药学杂志

ABSTRACT

OBJECTIVE: To establish and validate an infrared spectrometry method coupled with cluster analysis, principal component analysis and discriminant analysis for identifying different kinds of Hippocampus. METHODS: Fourier transform infrared (FT-IR) spectrometer was used to analyze the ethanol extracts from 35 samples of Hippocampus collected from different geographical locations. Similarity analysis and cluster analysis were used to establish the reference fingerprint spectra, and principal component analysis and discriminant analysis were used for identifying different kinds of Hippocampus. RESULTS: The samples of the same species had similar characteristic peaks of infrared spectra and could be clustered together. Based on the result of principal component analysis, the absorption peaks (3305.4-3297.7 cm-1, 2919.7-2915.9 cm-1, 2852.2-2848.4 cm-1, 1656.6-1652.7 cm-1, 1542.8-1538.9 cm-1, 1456.0-1452.2 cm-1 and 1045.2-1041.4 cm-1) were the main characteristic peaks and were used to develop the discrimination function for distinguishing different species of Hippocampus. The accuracy of the discrimination function was 93.55%. The established method had good stability, precision and reproducibility, and was a very reliable and useful method for distinguishing different species and assessment of the quality of Hippocampus. CONCLUSION: The established IR fingerprints of Hippo-campus's ethanol extracts coupled with mathematical statistics theory can be applied to identify different kinds of Hippocampus. More importantly, the research has provided a new thought for traditional Chinese medicine identification by using mathematical model.