Determining the authenticity of methyl salicylate in Gaultheria procumbens L. and Betula lenta L. essential oils using isotope ratio mass spectrometry

• Published in: The Journal of essential oil research Vol. 33; no. 5; pp. 442 - 451
• Main Authors: Murphy, Brett J., Carlson, Richard E., Howa, John D., Wilson, Tyler M., Buch, R. Michael
• Format: Journal Article
• Language: English
• Published: Taylor & Francis 03-09-2021
• Subjects: adulteration; Betula lenta; birch oil; essential oil; Gaultheria procumbens; Isotope ratio mass spectrometry (IRMS); methyl salicylate; wintergreen oil
• ISSN: 1041-2905; 2163-8152
• DOI: 10.1080/10412905.2021.1925362

The essential oils of wintergreen and birch are composed primarily of methyl salicylate. Because this compound can easily be synthesized, wintergreen and birch oils are frequently adulterated. By using Gas chromatography-combustion/pyrolysis-isotope ratio mass spectrometry (GC-C/P-IRMS) in conjunction with TC/EA-IRMS, GC-FID, GC-MS, and
14
C radiocarbon dating, criteria will be established that can be used to distinguish authentic and natural wintergreen and birch essential oils from adulterated ones or from synthetic methyl salicylate. Commercially purchased samples were compared to both synthetic 'oil of wintergreen' (methyl salicylate) and to natural birch and wintergreen essential oils obtained from trusted sources or from the steam distillation of fresh plant material. δ
2
H
VSMOW
, δ
13
C
VPDB
, and δ
18
O
VSMOW
IRMS results provide a clear distinction between authentic and adulterated essential oil samples.