Planta Med 2014; 80 - P1M16
DOI: 10.1055/s-0034-1394583

A rapid and economical quality control method for lavender oil using the combination of vibrational spectroscopy and chemometric analysis

S Tankeu 1, I Vermaak 1, G Kamatou 1, A Viljoen 1
  • 1Department of Pharmaceutical Sciences, Faculty of Science, Tshwane University of Technology, Private Bag X680, Pretoria, 0001, South Africa

Lavandula angustifolia (Lamiaceae), one of the top ten medicinal plants, is used and traded extensively in the flavour and fragrance, aromatherapy and cosmetic industries [1]. However, as the essential oil profile is highly variable due to environmental factors etc. this necessitates the development of reliable and fast techniques for quality assessment [2]. The complex essential oil is traditionally analysed using gas chromatography coupled to mass spectrometry with a flame ionisation detector (GC-MS-FID). In this study, vibrational spectroscopy methods such as mid infrared (MIR) and near infrared (NIR) in combination with chemometric data analysis are proposed as an alternative method for the routine quality assessment of lavender oil. Sixty lavender oil samples were sourced from various suppliers and analysed using GC-MS-FID. Spectral data were collected for the MIR (4000 – 550 cm-1) and NIR (10 000 – 4000 cm-1) wavelength regions and chemometric analysis was performed to construct calibration models for six compounds including linalyl acetate, linalool, cis-β-ocimene, trans-β-ocimene 1,8-cineole and camphor. Calibration models with good statistical values were obtained, indicated by the high coefficients of determination (R 2) ≥0.82 and low errors (≤1.6) of estimation (RMSEE) and prediction (RMSEP). The calibration models for the major compounds linalool and linalyl acetate (> 70% of the total composition) had high coefficients of determination (R2): 0.99 (MIR) and 0.98 (NIR) and 0.92 (MIR) and 0.90 (NIR), respectively. An external dataset was accurately predicted as evidenced by comparison with the reference data.

Keywords: Lavender, quality control, vibrational spectroscopy, metabolomics

References:

[1] Vincent, E. 2008. Lavender essential oil. Available at http://www.youngliving.com. [Accessed on 2013/01/20].

[2] Lawless, J. 2013. The essential oils: the complete guide to the use of aromatic oils in aromatherapy, herbalism, health and well-being. Conrad Press Edition. 315.