Chemistry of Essential Oils

(Tuis.) #1

152 THE CHBMISTEY OF ESSENTIAL OILS


from other parts of the plant than the leaves and found them to have
the following characters :—
Specific gravity 0-8942 to 0'8947
Optical rotation - 14° 29' ,, - 22° 26'
Ester value 27-3 „ 29*9
They found present in the oil cineol, linalol, geraniol, and geranyl
esters.
OILS OP PERSEA.
Persea gratissima is a tree indigenous to tropical America. The
bark yields about 3*5 per cent, of essential oil having the following
characters :—
Specific gravity. 0'969
Optical rotation - 0° 46'
It contains anethol and methyl-chavicol (hence its original descrip-
tion as " anise bark " oil).
The leaves yield an oil of tarragon-like odour having the following
characters :—
Specific gravity 0*955 to 0 961
Optical rotation + 1° 50' „ + 2° 30'
Refractive index 1-5120 „ 1-5150
Acid value 0
Ester „ 2 to 4
„ „ (after acetylation) 18 ,, 22
The principal constituent is methyl-chavicol, with a little pinene

. and a small amount of a solid paraffin.
Babakl has examined the essential oil distilled from the leaves of
the so-called " swamp bay," Persea pubescens, a North American tree.
He obtained 0*2 per cent, of oil of the following characters :—
Specific gravity..0-9272 at 25°
Optical rotation
Refractive index
Acid value.
Ester
(after acetylation)


+ 22° 4'


1-4695 at 25°
2-8
14-5
64
He found it to contain butyric acid in the free state, and butyric,
valerianic, and oenanthylic acids as esters. Camphor, cineol, and pro-
bably borneol are also present, as well as traces of formaldehyde.

OIL OF PICHURIM.

The cotyledons of Nectandra Puchury major- and Nectandra Puck-
ury minor, two species of Lauracea indigenous to Brazil, and commonly
known as the Para nutmeg, yield about -5 to 1 per cent, of a yellowish-
green oil. According to Muller, the oil contains several oxygenated
constituents not completely identified. Esters of lauric and valerianic
acids are probably present. It distils between 180° and 270° and contains
a terpene and probably a little safrol. The fraction boiling at 256° has
a deep blue colour.
Eoure-Bertrand Fils^2 have examined the oil distilled from the
Puchury-major bean alone, which they obtained in a yield of 2*3 per
cent. It has a characteristic odour of sassafras, with a suggestion of
nutmeg and cloves. Its characters are as follows:—
1
U.S. Dept. of Agriculture, Bureau of Plant Industry, 235 (1912), 29.
^Bulletin, April (1920), 4, 1, 35.
Free download pdf