Arbitrating Identification Issues of Picrorhiza kurroa Samples by ATR-FTIR Spectroscopy Using Multivariate Analysis

Picrorhiza kurroa Royle ex Benth (Scrophulariaceae) has been utilized globally and is among endangered perennial herbs. The fundamental concerns in quality control of P. kurroa arise due to its part of medicinal value. In the present study, attenuated total reflectance/Fourier transform infrared (ATR/FTIR) technique was used to analyze both authenticated and commercial samples of P. kurroa. A total of 11 different samples were examined and the spectra in transmittance mode were recorded without using KBr pellets. Fingerprint region of the spectra was considered for further treatment with multivariate analysis tools. Chemometric techniques, including principal component analysis (PCA), hierarchiucal cluster analysis (HCA), K-means cluster analysis (KMCA), and Kohonen self-organizing maps (SOMs) were used to identify the samples of P. kurroa. Thus, the proposed method can be used as a tool to discriminate authentic samples of P. kurroa from its adulterants and substitutes.