Volatiles from herbs and spices 187
underground rhizome or tap root of several species of Ferula (three of which grow in
India), which is a perennial herb (1 to 1.5 m high). It is greyish-white when fresh,
darkening with age to yellow, red and eventually brown. It is sold in blocks or pieces
as a gum and more frequently as a fine yellow powder, sometimes crystalline or
granulated. Studies conducted in Pakistan on fresh mature seed oils of Ferula foetida
Regel indicated presence of a-pinene (1.69–2.36%), camphene (0.9–1.04%), myrcene
(2.0–2.5%), limonene (0.60–0.72%), longifolene (1.60–5.9%), caryophyllene (3.8–
5.0%), b-selinene (15.2–17.2%), eugenol (4.68–5.00%), bornyl acetate (2.25–4.5%),
fenchone (1.5–2.4%), linalool (0.05–0.06%), geraniol (0.05–0.08%), isoborneol
(0–0.4%), borneol (0–0.15%) and guaicol (0.57–0.9%). The oil was also found to
contain a mixture of sesquiterpene alcohols (0–39.32%) and a mixture of coumarins
(7.5–7.8%) (Ashraf and Bhatty 1979).
The major constituents of asafoetida are the resin (40–64%), gum (25%) and
essential oil (10–17%) (Abraham et al. 1979). The aroma of asafoetida is attributed
mainly to secondary butyl propenyl disulphide. Using MS, NMR, IR and UV spectra
these were further characterized as 1-methyl propyl-(1-propenyl) disulphide (secondary
butyl-(1-propenyl)-disulphide), 1-methyl thiopropyl-(1-propenyl) disulphide and 1-
methyl propyl-(3) methyl-thio-(2-propenyl) disulphide (sec.butyl-(3)-methylthioallyl-
disulphide): the composition of these in asafoetida oil is 36–84%, 9–31% and 0–
52%, respectively (Abraham et al. 1979, Lawrence 1981) (Fig. 11.6).
Pakistan sample of asafoetida contained 1-(methylthio)-propyl–(E)-1-propenyl
disulphide (37.93%), 1-(methylthio)-propyl-Z-1-propenyl disulphide (18.46%), 2-
butyl–(E)-1-propenyl disulphide (11.17%), dibutyl trisulphide (1.82%), isobutanol
(7.65%), methyl–(E)-1-propenyl disulphide (1.69%) as major compounds (Noleau et
al. 1991). Essential oils extracted from asafoetida gums contained more than 150
compounds of which 25 compounds, including 13 sulphur-containing compounds,
were common to both leek and asafoetida (Noleau et al. 1991).
The oil from Iran was constituted by a-pinene (2.1%), sabinene(1.0%), b-
pinene(5.0%), myrcene (1.0%), a-phellandrene (2.4%), b-phellandrene (2.5%), Z-b-
ocimene (11.5%), E-b-ocimene (9.0%), 2-butyl-1-propyldisulphide (0.6%), 2-butyl-
Z-1-propenyldisulphide (3.9%), 2-butyl-E-1-propenyldisulphide (58.9%), di-1-
methylpropyl disulphide (0.3%) and di-1-methyl-propenyl disulphide (1.2%) (Sefidkon
et al. 1998).
Basil
The chemical composition of volatile oils obtained from two forms of sweet basil
Fig. 11.6 Volatiles from asafoetida.SS
S
1-methyl propyl (3-methylthio-2-propenyl) disulphide1-methyl propyl-(1-propenyl) disulphideSS S
SS1-methylthiopropyl-(1-propenyl) disulphide