Characterization of Neem (Azadirachta indica A. Juss) seed volatile compounds obtained by supercritical carbon dioxide process.

Extraction process employing Supercritical fluid
carbon dioxide (SCF) yields bioactive compounds near
natural forms without any artifact formation. Neem seed
was subjected to SCF at different temperatures and pressure
conditions. These extracts were partitioned to separate
volatile fraction and were analyzed by Gas Chromatography–
Mass spectroscopy along with the volatiles extracted
by the hydro-distillation method. Experimental results
show that there is a significant effect of pressure and
temperature on isolation of a number of volatile compounds
as well as retention of biologically active compounds.
Twenty-five volatile compounds were isolated in
the Hydro-distillate compare to the SCF extract of 100 bar,
40 �C which showed forty volatile compounds corresponds
to 76.38 and 92.39% of total volatiles respectively. The
majority of bioactive compounds such as Terpinen-4-ol,
1,2,4-Trithiolane, 3,5-diethyl, allyl isopropyl sulphide,
Cycloisolongifolene, a´-Bisabolene, (-)-a-Panasinsen, Isocaryophyllene,
trans-Sesquisabinene hydrate, 1-Naphthalenol,
were identified in the extract when isolated at
100 bar and 40 �C.