Chemistry of Essential Oils

LABIATE 247

The oil has the following composition :—

d-a-pinene

Cineol

Phenols.

Ketones.

Esters

Free alcohols

7 to 8 per cent.

64 „ 72 „

traces

it

4 to 6-5 per cent, (linalyl acetate)

8 to 14 per cent.

OILS OF MARJORAM AND ORIGANUM.

Some confusion has existed in regard to the botanical origin of the
various origanum or marjoram oils of commerce. This confusion is well
cleared up by Holmes,^1 who gives the following details concerning the
plants.
The oil known as oil of sweet marjoram is derived from Origanum
majorana:—
" The plant is known in this country as sweet, knotted, or garden
marjoram, to distinguish it from the wild marjoram, Origanum vulgare,
which differs from it both in appearance and odour. In France
Origanum majorana is known to botanists and florists as * Marjolaine
douce/ the wild marjoram being called ' Marjolaine sauvage'. In
Germany it is known as ' Meiran '. It is supposed to be a native of
Mediterranean countries, and has been cultivated as a pot herb from the
earliest times, being used for this purpose by the ancient Egyptians. It
was introduced into this country from North Africa in A.D. 1573, but it
is hardly known in a truly wild state in Europe, and its native country
must be regarded as doubtful. Other species were, however, and are
still, used in southern Europe.
" Although still cultivated at the present day in almost all countries
for culinary purposes, the oil is chiefly distilled in and imported from
Spain.
" The plant is a small bushy herb, usually about 12 or 18 ins. high,
with small ovate, stalked, greyish-green, entire, somewhat hairy leaves,
and small, rounded, stalkless heads of flowers forming greenish clusters
at the top of the stems and upper branches, the small white blossoms
being rather inconspicuous, and almost hidden among the crowded
green bracts. There is a variety of the plant with woody perennial
stems which was cultivated by herbalists in this country in the eighteenth
century, and was distinguished by the botanist Willdenow as Origanum
majorancides. This is the plant that yields the oil distilled in Cyprus."
"Holmes points out that, it is generally recognised that the oil of
marjoram coming from a definite port or place of manufacture, is not
always identical in composition or constituents. Origanum oil from
Trieste sometimes yields carvacrol and sometimes thymol, in different
samples, and the same occurs in oils imported from Smyrna and from
Cyprus. It would appear, therefore, that more than one species is em-
ployed in the manufacture of the oil in each district.
" The oils have been attributed to various species of Origanum, but the
statements do not afford any definite information in cases in which
the botanical authority for the name is not given. Thus there are three
different species of Origanum bearing the name of Origanum Creticum,
and two bearing that of Origanum Smyrnceum, and two bearing that of
Origanum hirtum, so that the use of either of these names is of no

i P. and E.O.R. (1912), 322 ; (1913), 741.