红外光谱结合化学计量学鉴别美洲大蠊及其他虫类药材研究

Discrimination of Periplaneta americana and other insectivorous herbs by FTIR spectroscopy combined with chemometrics

目的基于红外光谱法结合化学计量学建立美洲大蠊及其他虫类药材(全蝎、水蛭)粉末的鉴别方法,为美洲大蠊的鉴别提供一定的依据。方法运用傅里叶变换红外光谱仪采集3种虫药药粉的红外光谱数据,对已得光谱数据二阶求导后运用纵坐标归一化法、标准化法等预处理方法对光谱进行优化,采用化学计量学,包括系统聚类分析(hierarchicalcluster analysis,HCA)、主成分分析(principal component analysis,PCA)以及偏最小二乘判别分析(partial least squares discriminant analysis,PLS-DA)进一步对光谱数据进行分析。结果美洲大蠊与全蝎、水蛭的红外指纹图谱有差异。美洲大蠊在1 711、1 410、712 cm-1处吸收峰明显,全蝎在1 753、1 400、1 168、717 cm-1处吸收峰明显,水蛭在1 558、1 457、1 400、669 cm-1处吸收峰明显,且水蛭在1 753~1 711cm-1处明显无吸收峰。3种虫类药材在1 800~1 700 cm-1处峰形差异明显较大。二阶导数图谱中,主要峰的位置相同,但共有峰的强度不同。运用HCA分析方法发现3种虫类药材能够被快速区分,运用PCA与PLS-DA分析方法发现3种虫类药材分布在不同区域。结论本研究能够简便、快速的鉴别美洲大蠊与全蝎、水蛭等虫类药材,为美洲大蠊的质量控制及评价提供参考。

Objective To establish a method for the identification of the Periplaneta americana and other insectivorous herbs(Scorpio and Hirudo) based on infrared spectroscopy combined with chemometrics, and to provide a basis for the identification of the P. americana. Methods Fourier transform infrared spectroscopy was used to collect the infrared spectrum data of three kinds of insect medicine powders. After the second order derivation of the obtained spectral data, the ordinate verticalization method and standardization method were used to optimize the spectrum. The spectral data was further analyzed by chemometrics, such as hierar chicalcluster analysis(HCA), principal component analysis(PCA) and partial least squares discriminant analysis(PLS-DA). Results There were differences in the infrared fingerprints of the P. americanas, Scorpios, Leeches. The absorption peaks of the P. americanas at 1 711, 1 410, and 712 cm-1 were obvious. The absorption peaks of the Scorpios at 1 753, 1 400, 1 168, and 717 cm-1 were obvious. The absorption peaks of the Leeches at 1 558, 1 457, 1 400, and 669 cm-1 were obvious, And the leeches have no absorption peak at 1 753-1 711 cm-1. The peak shape of the three insectivorous herbs was significantly different at 1 800-1 700 cm-1. In the second derivative spectrum, the positions of the main peaks are the same, but the intensity of the common peaks is different. Using the HCA analysis method, it was found that the three insectivorous herbs could be quickly distinguished. The PCA and PLS-DA analysis methods were used to find that the three insectivorous herbs were distributed in different regions. Conclusion Infrared spectroscopy combined with chemometrics can easily and quickly identify the P. americanas and other insectivorous herbs(Scorpios and Leeches), and provide reference for the quality control and evaluation of P. americanas.