Effect of rotational ambiguity on produce a set of feasible solution for overlapping peaks in analysis of volatile components of Verbena Officinalis L. using gas chromatography - mass spectrometry

چکیده مقاله

The essential oil of Verbena Officinalis L. (Vervain) was extracted by applying simultaneous distillation extraction (SDE) method and studied with gas chromatography- mass spectrometry (GC-MS). Due to several problems such as low signal-to-noise (S/N) ratio of peaks, varying baseline due to column bleed, noisy data and co-elution; the obtained data from their components cannot be used directly to satisfactory qualitative and quantitative analysis. Therefore, the resolution of the overlapping GC-MS signal is a challenging and active research field. In this research for resolving of overlapped peaks, Manne’s theorem [1] was investigated by fixed size moving window evolving factor analysis (FSMW-EFA) [2]. In the next step, multivariate curve resolution-alternating least square (MCR-ALS) [3] was used for resolving the overlapping peaks into pure chromatogram and pure mass spectra. For better understanding of existence of rotational ambiguities, the area of feasible solutions (AFS) based on polygonal inflation algorithm (PIA) is computed only on the condition of nonnegativity [3] and also the effect of suitable constraints on reducing of rotational ambiguity was surveyed by MCR-BANDS [4]. In addition, in this study, presence of valuable components such as Curcumene (20.96%), Eudesmol (5.35%), a-Pinene (0.38%) and Eucalyptol (0.15%) in Vervain oil have been verified.