Chemistry of Essential Oils

LABIATE 261

It is soluble in 8. volumes of 80 per cent, alcohol, sometimes with

slight turbidity.

Two samples of Mayotte oil examined by Eoure-Bertrand Fils

l

had

the following values :—

1. 
   
   
   
   2. Specific gravity at 15° C..
      Optical rotation.
      Solubility in 80 per cent, alcohol
      Acid value
      Coefficient of saponification
      Esters (as linalyl acetate).
   
   
   
   

0'9677

+ 0° 58'

. 3 volumes and over
1-4
5-6
1*9 per cent.

0-9630

+ 0

°
56'
3'2 volumes and over
0-7
6-3
2-2 per cent.
Two varieties of Java oil have been examined in the laboratories at
Buitenzorg. One is that from a large-leaved variety known as " Selasih
Mekah ". The oil had a specific gravity 0900 at 26° and an optical
rotation of - 15° to - 18°. It contained about 30 to 40 per cent, of
phenols, of which eugenol is stated to be the principal.
A sample of the oil distilled in the Seychelles^2 had the following
characters :—
Specific gravity 0962
Optical rotation +0*82°
Befractive index at 21° 1-5140
Acid value 0-8
Ester 2-5
Another variety of the plant yielded an oil of specific gravity 0

• 948
  at 25° and containing much methyl-chavicol. This plant is known as
  Selasih hidjan.
  Dupont and Guerlain
  3
  have identified methyl-chavicol (estragol) and
  linalol in the oil. Bertram and Walbaum 4 isolated cineol, d-u-pinene,
  and ^-camphor.
  The Java oil contains cineol, estragol, pinene, an olefinic terpene
  (ocimene?), and eugenol.
  Koure-Bertrand Fils^6 have examined the oils of Ocimum canum and
  Ocimum gratissimum, distilled at Dakalba (Ivory Coast).
  The essential oil of Ocimum canum Sims (0. americanum L.) con-
  sists, when slightly heated in the hand, of a mobile liquid, highly re-
  fractive, slightly yellowish. Its odour is peculiar and rather pleasant.
  At the time of its preparation it collects at the bottom of the receiver.
  At the ordinary temperature it soon gives a deposit of large acicular
  crystals. The separation of crystals is sufficiently abundant to cause
  the whole product to become semi-solid.
  The oil has the following characters :—
  Specific gravity at 32° C. 10330
  Optical rotation at 30° C - 2° 80'
  Acid value .......... 0
  Coefficient of saponification 301-4
  Soluble in all proportions in 80 per cent, alcohol.
  „ „ 2J volumes and over of 75 „ „
  Solution slightly cloudy in 5J volumes and over of 70 per cent, alcohol.
  It was found to contain about 87 per cent, of methyl cinnamate, of
  which ester the crystals above mentioned consist.
  The oil from Ocimum gratissimum has a specific gravity 09105 and
  an optical rotation + 0° 58'. It contains thymol and carvacrol.

(^1) Bulletin, October, 1912, 71. (^2) Bull. Imp. Inst., xvi., I, 30.

• Comptes rendus, 124 (1897), 300.^4 Arch. Pharm., 235 (1897), 176.
  « Bulletin, October, 1913, 18.