Chemistry of Essential Oils

(Tuis.) #1

UMBELLIFEE^ 313


to 211°), another body, melting-point 200° to 201°, crystallising in thin
prisms. This latter semi-carbazone was not found in the other frac-
tions. Further examination failed to confirm the surmise that the two
semicarbazones of cuminic aldehyde contained cis- and tfrans-modifica-
tions. When oxidised with chromic acid, the aldehyde forming the
basis of the semicarbazone of the melting-point 200° to 201° was also
converted into cuminic acid. The oxime of the aldehyde had a melt-
ing-point 72° to 76° (impure). It is therefore probable that, in addition
to the cuminic aldehyde, tnere is present, in small proportions, a hydro-
genated cuminic aldehyde.
A Persian cummin seed has recently been found on the London
market. This has been examined by Holmes,
1
who reported as follows
on the seed:—
" The appearance of a fruit under this name on the London market is
of considerable interest, inasmuch as its botanical source has never been
identified with certainty, and so far as I am aware there is no authenti-
cated specimen of the Persian plant yielding it in any European Herbar-
ium. This fruit has been in the museum of the Pharmaceutical Society
in London for at least thirty years under the name of Carum nigrum.
"The botanical and indeed the geographical source of Persian
'Cummin, which is distinguished at Bombay as * Zeerah Shiah,' i.e. black
•cummin (in contra-distinction from ' Zeerah Suffed,' i.e. white cummin,
the name applied to the cummin fruit, Cuminum cyminum, used in
Europe), is at present not clearly determined, since there are ap-
parently two or three different, but closely allied, fruits having the
cummin flavour, and collected apparently in widely different districts
in or about the 30th parallel of N. latitude, and all bearing the name of
black cummin.
" The Persian cummin is believed to have come from Mohammerah,
near the north-west coast of the Persian Gulf, in the Province of
Khuzistan, but of the plant that yields it nothing is known. The
fruit, however, agrees in structure with a fruit from Kunawar, in the
north-east of the Punjab, which is stated by Dr. Koyle (Illustrations of
Himalayan Botany, p. 229) to be collected there under the name of
' Zeerah Shiah/ or black cummin, and he suggests the name of Carum
nigrum for the plant, but gives no description of it. He evidently sent
the plant, however, to Dr. Lindley, who was at that time professor of
botany at the London University, since in the Lindley Herbarium,
which is now in the Botanical Museum of Cambridge University, a
specimen of a Carum received from Dr. Eoyle, occurs, which is named
Carum gracile Lindl. This name, with Lindley's description, occurs
on page 232 of the same work without any reference to Koyle's Carum
nigrum, so that it is evident that Dr. Eoyle sent it to Dr. Lindley un-
named, and Lindley's name for the plant must therefore supersede Dr.
Boyle's Carum nigrum."
The yield of oil from the seeds was 2 per cent., and it has been
^examined by Umney
2
who found it to have the following characters :—
Persian Cummin Oil.
Yield.2 per cent.
Specific gravity
Optical rotation ...
Refractive index ......
Aldehydes by absorption with sodium bisulphite


•911


+ 7°


1-4980


18 per cent.

(^1) P. and E.O.R. (1913), ±3. (^2) Ibid.

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