Optimization of the Supercritical Carbon Dioxide Separation of Bergapten from Bergamot Essential Oil

J AOAC Int. 2018 Jan 1;101(1):293-297. doi: 10.5740/jaoacint.17-0190. Epub 2017 Jul 31.

Abstract

The possibility of following traditional cold-press extraction with the post process continuous separation of bergapten from bergamot essential oil was investigated. A fractionation tower was used in an experiment in which cold-pressed bergamot oil was extracted in a continuous countercurrent process by supercritical carbon dioxide under different conditions. Bergapten is fairly soluble in CO2 in its supercritical phase, in particular at a density of 277.90 kg⋅m-3, corresponding to a pressure of 8 MPa and temperature of 40°C. Under these conditions, an extract with 0.198% bergapten was obtained, a figure slightly below the percentage of bergapten contained in cold-pressed oil (0.21%). However, at densities below 200 kg⋅m-3, the amount of bergapten in the extracted oil was negligible. Of all tested conditions for separation, the best was found to be at a pressure of 8 MPa and temperature of 70°C, conditions under which bergapten was not detected. The results of the experiment showed that bergapten, and the non-volatile fraction in general, was extracted only in small quantities and was not extracted at all with at a CO2 pressure of 8 MPa.

MeSH terms

  • 5-Methoxypsoralen
  • Carbon Dioxide / chemistry
  • Carbon Dioxide / isolation & purification*
  • Methoxsalen / analogs & derivatives*
  • Methoxsalen / isolation & purification
  • Oils, Volatile / chemistry*
  • Plant Oils / chemistry*

Substances

  • Oils, Volatile
  • Plant Oils
  • Carbon Dioxide
  • bergamot oil
  • 5-Methoxypsoralen
  • Methoxsalen