Chemistry of Essential Oils

HAMAMELIDACE^E 525

The fruit of Pittosporum resiniferum yields 0*5 per cent, of essential
oil, obtained by expression, having the following characters :—

Specific gravity 0883
Refractive index 14577
According to Bacon,
1
the oil contains heptane, and a dihydroterpene,
C 10 H 18 , having the following characters :—
Boiling-point 168° to 170°
Specific gravity at —00805 03O°
Optical rotation + 1° 6'

Refractive index at 30°..1-4460

HAMAMELIDACE/E.

OIL OF STORAX.

The oleo-resinous substance obtained from the bark of the tree Liqui^

dambar orientale, a plant found chiefly in Asia Minor, constitutes the

liquid storax of commerce.

The oleo-resinous balsam yields from O5 to 1 per cent, of essential oil

having the following characters :—

Specific gravity...0-950 to 1-050 (sometimes lower)

Optical rotation.

Refractive index

Acid value.

Ester „.

+ 1° to - 35°

1-5395 „ 1-5653

1 „ 26

up to 130

The very variable characters of this oil are due to differences in dis-

tillation methods, as the further the distillation is carried, the more the

amount of slightly volatile, high gravity constituents corning over.

The principal odorous constituent of the oil is styrol, or phenylethy-

lene C 6 H 6. CH : CH 2 , an optically inactive hydrocarbon boiling at 146°.

The cinnamic acid esters of ethyl, benzyl, phenyl-propyl, and cinnamyl

alcohols are also present, as well as the free alcohols, and traces of

vanillin.

The oil is adulterated with artificial esters, notably benzyl benzoate.

The volatile oil from the leaves and twigs of Liquidambar Formosana

has been examined by Kafuku.^2 • A yield of about 0*05 per cent, was ob-

tained. It was greenish-yellow in colour, having a specific gravity of

0-8655 at 20° C., Optical rotation - 3'3°, refractive index 1-4755 at 20° C.,

acid value nil, ester value 5*9, ester value after acetylation 25'2. It con-

sisted principally of terpenes ; camphene, a-pinene, and dipentene were

identified with certainty, nopinene and phellandrene being also indicated.

Traces of aldehydes and ketones were found to be present.

OIL OF HAMAMELIS VIBGINIANA.

The oil obtained from Hamamelis Virginiatia has the following char-

acters :—

Specific gravity....0-900 to 0-906

Optical rotation

Refractive index

Ester value

(after acetylation)

+ 4° „ + 5°

1-4830 „ 1-4895

about 4

„ 30

Philipp. Jour. Sc.t 4 (1909), 115. *Jour. Chem. Ind. Tokio (1916), 19, 516..