Study On Fourier Transform Infrared Spectra Of Peony And Cortex Moutan

The conventional method to identify peony varieties is based on morphology, which is strongly subjective, and lacks chemical information. The method to study genetic relationships of different tree peony cultivars is based on molecular marker technique, which is strongly complicated and time-consuming. Based on the traditional methods to identify the standard and false cortex moutan have the disadvantages of limitation, complexity and subjectivity. Fourier transform infrared spectroscopy technology combined with statistical analysis have been applied to research the identification of tree peony varieties, the genetic relationships of different tree peony varieties, and the quality identification of cortex moutan.The infrared spectra of peony samples are similar on the whole, which are mainly composed of the vibration absorption bands, such as protein, phenolic, lipid, glycosides, polysaccharides, flavonoids and so on. The first derivative spectra of 1800~700 cm-1 are selected using Matlab program to perform principal component analysis(PCA) and correlation analysis. PCA yields 96% correct classification, and the results of correlation analysis are identical with principal component analysis each other.Fourier transform infrared(FTIR) spectroscopy combined with Hierarchical clustering analysis(HCA) was used to study the genetic relationships of different Tree Peony cultivars in this study. The cluster results were correlated with flower colors, forms or plant types of tree peony cultivars, and the tree peony cultivars of different origins had rather distant genetic relationships, which suggested selecting foreign cultivars obviously different of domestic cultivars as a parent in the future breeding work.Fourier transform infrared spectroscopy combined with second derivative spectra and two-dimensional correlation infrared spectroscopy was applied to identify the qualified cortex moutan, defective cortex moutan and false cortex moutan. The infrared spectra of three kinds of samples are similar on the whole. In light of second derivative spectra, the absorption intensity of 1626 cm-1 in Tongling is absolutely higher than the cortex moutan of Luoyang and the paeonia lactiflora pall of Haozhou. The absorption intensity in 1317 cm-1 of the three samples which in descending order were: cortex moutan in Tongling, cortex moutan in Luoyang, paeonia lactiflora pall in Haozhou. The absorption intensity in 856 cm-1 of the three samples which in descending order were: cortex moutan in Luoyang, paeonia lactiflora pall in Haozhou, cortex moutan in Tongling. By two-dimensional spectra in the range of 1730~1380 cm-1 and 1000~500 cm-1, the three samples were visually distinguished due to their significant differences in auto-peak profile. The result showed that Fourier transform infrared spectroscopy combined with second derivative spectra and two-dimensional correlation infrared spectroscopy can be successfully applied to research and identify cortex moutan rapidly from different geographical regions and would be successfully applicable to the analysis and identification of quality standards of Chinese medicinal resources.