Abstract:

The optimal conditions for supercritical CO2 extraction of essential oil from fresh flower of Elaeagnus
angustifolia L were explored by response surface methodology (RSM). A three-level Box-Behnken factorial design was
used to investigate the effects of three independent variables such as extraction pressure, extraction temperature and
extraction time on the yield of essential oil. Results showed that the optimal extraction process conditions for supercritical
CO2 extraction of essential oil from fresh flower of Elaeagnus angustifolia L. included extraction pressure of 3400 psi
(23.45 MPa), extraction temperature of 58 ℃, and extraction duration of 4 h. Under these extraction conditions, the yield
of essential oil was up to 2.41‰. Meanwhile, 26 compounds were identified in the extract by GC-MS. Among them, ethyl
cinnamate was the most dominant followed by (E)-9-octadecenoic acid ethyl ester and n-hexadecanoic acid. In addition,
relatively high amounts of n-propyl acetate, 2-pentadecyn-1-ol and 9-octadecenal (Z) were also found in the extract. Apart
from ethyl cinnamate, aromatic alcohols and ketones appeared to contribute to the aroma of the essential oil.

Key words: Elaeagnus angustifolia L., essential oil, supercritical CO2 extraction, GC-MS