Chemometric Resolution Approaches in Characterisation of Volatile Constituents inPlantago ovataSeeds using Gas Chromatography-Mass Spectrometry: Methodology and Performance Assessment

Abstract

Comprehensive chemical profiling of herbal medicines (HMs) is a major challenge in chemical characterisation of source materials. Many analytical platforms such as gas chromatography-mass spectrometry (GC-MS) have been applied to the characterisation. However, the great complexity of analytical results has been an obstacle. Chemometric resolution methods as a supplementary tool for data processing are proposed for solving this problem. To develop and demonstrate the ability of chemometric techniques in the characterisation of volatile components in herbal medicines. The volatile components of Plantago ovata were extracted using a solvent extraction method. GC-MS analysis were performed using an Agilent HP-6890 gas chromatograph equipped with a HP-5MS capillary, interfaced with an Agilent HP- 5973 mass selective detector. Resolved spectra were identified by matching against the standard mass spectral database of the National Institute of Standards and Technology (NIST). Results of this study show that the 71 constituents that are qualitatively recognised represent 94.53% of the total relative content of constituents from Plantago ovata oil, whereas without applying the chemometric methods only 51 constituents were recognised by direct searching utilising a mass database. In addition the presence of valuable components such as thymol, 2,4-decadienal, linoleic acid and oleic acid in Plantago ovata oil has been demonstrated. GC-MS combined with chemometric resolution methods, such as multivariate curve resolution-alternating least squares (MCR-ALS), will provide a reliable means for rapid and accurate analyses of unknown complicated practical systems.