Vibrational spectroscopic studies to acquire a quality control method of Eucalyptus essential oils

Abstract

This article presents a novel and original approach to analyze in situ the main components of Eucalyptus oil by means of Raman spectroscopy. The obtained two-dimensional Raman maps demonstrate a unique possibility to study the essential oil distribution in the intact plant tissue. Additionally, Fourier Transform (FT)-Raman and attenuated total reflection (ATR)-IR spectra of essential oils isolated from several Eucalyptus species by hydrodistillation are presented. Density Functional Theory (DFT) calculations were performed in order to interpret the spectra of the essential oils of the Eucalyptus species. It is shown that the main components of the essential oils can be recognized by both vibrational spectroscopic techniques using the spectral information of the pure terpenoids. Spectroscopic analysis is based on the key bands of the individual volatile substances and therefore allows one to discriminate different essential oil profiles of several Eucalyptus species. It has been found that the presented spectroscopic data correlate very well with those obtained by gas chromatography (GC) analysis. All these investigations are helpful tools to generate a fast and easy method to control the quality of the essential oils with vibrational spectroscopic techniques in combination with DFT calculations. #

Handheld Raman Spectroscopy for the Distinction of Essential Oils Used in the Cosmetics Industry

“…Despite the differences in the Raman spectra, there are certain common features related to functional groups in compounds present in essential oils. At least one band in the vicinity of 1450 cm −1 attributed to bending modes of CH3 and CH2 groups [27] can be expected in the Raman spectra of all essential oils considered in this study. Bands in this region can be weaker or stronger, depending on the presence of CH3 and CH2 groups in the compounds of the essential oils and cannot easily be attributed to specific compounds, since most of the compounds have CH3 and CH2 groups in their structure.…”

Aromatherapy and nursing: historical and theoretical conception

“…Studies have been conducted with energetic measurements of essential oils using Raman spectroscopy (23)(24) , which is based on the incidence of a monochromatic light source which, upon reaching the oil in question undergoes scattering of light, allowing researchers to obtain information about the chemical compound indicating that the components show energy bands. These studies support the existence of energy in essential oils, proposing that the use of these plant concentrates can act in line or changing energy patterns of an organism.…”

Identification and quantification of valuable plant substances by IR and Raman spectroscopy

“…Assignment for the most characteristic Raman and IR bands of some terpene compounds[37][38][39][40][41][42][43][44][45][46][47] …”