Oleum Andropogonis muricati. - Vetiverol. - Essence de Vetiver.
Origin and Production. Vetiver oil is obtained by the distillation of vetiver root. It is derived from Vetiveria zizanioides, Stapf (Andropogon muricatus, Retz.; A. squarrosus, Hack.; Vetiveria muricata, Griseb. a. o.)2), or vetiver grass, Vettiver, or known in Java as Akar wangi, in India as Cus-Cus or /(has /(has, a name that is probably of Hindostanic origin and signifies "aromatic root".
Since an early period the roots have been woven artistically into baskets, covers and mats. The latter are hung in doors and windows and in hot weather are frequently moistened with water, thus perfuming and cooling down the atmosphere.
Vetiver grass occurs both wild and cultivated and is highly prized on account of its roots which find manifold application. The wild plant occurs throughout India proper and Ceylon, more particularly along the shores of rivers and in rich marsh bottoms, to an altitude of 600 m. Occasionally it is cultivated, e.g. in Rajputana and Chutia-Nagpur. In Malay territory vetiver occurs only as cultivated plant or having escaped cultivation. This also holds true of the West Indies1), Brazil2), Re'union and Java.
1 Philippine Journ. of Sc. 0 (1911), A, 351. 2) Kew Bull. 1906, 346.
According to Bacon') vetiver also occurs in the Philippines, where the natives designate the roots as Moras or Raiz Moras. The plant is further cultivated in Martinique4), the Seychelles, in Amani5) and in Momba.
The best varities of this species of grass are found in the neighborhood of Tutikorin, which up to this date is the most important port for the export of vetiver. In cultivating vetiver the tufts are torn apart and the individual plants set out in light soil. In the Philippines4) the hectare is said to yield 18 000 kg. of roots. The oil content of the roots increases up to the flowering period of the plant, hence it would seem rational to harvest and distil the roots within the first 3 months. Here also the plants are propagated by root division. The sowing of seed has not been attempted.
Cultural experiments made in Buitenzorg with the plant known as Akar wangi, the non-flowering variety of Andropogon muricatus occurring in Java6), have revealed that shade is apparently unfavorable to root development, whereas it is stimulated by repeated cutting of the plant.
The root is reddish and frequently rendered impure by a large amount of red sand. Frequently very pale roots are met with in commerce which yield but a very small amount of oil. It was formerly supposed7) that these roots had been partly exhausted by distillation. The opinion of G. Watt8), however, appears more rational, viz. that these roots have served as mats and have frequently been sprinkled with water to cool off the houses, and that upon repeated drying much of the volatile oil has evaporated with the water.
1) Dymock, Warden and Hooper, Pharmacographia indica. Part VI, p. 571, and Sawer, Odorographia. Vol. I, p. 309.
2) Peckolt, Kata/og zur National-Ausstellung in Rio 1866. pp. 22 and 48. - Pharm. Rundschau 12 (1894), 110.
3) Philippine Journ. of Sc. 4 (1909) A, 118.
4) Report of Roure-Bertrand Fils, April 1908, 24.
5) Report of Schimmel & Co. April 1905, 84; April 1907, 102. 6) Jaarb. dep. landb. in Ned.-Indie, Batavia 1910, 48.
•) First Edition of this treatise, p. 289.
8) G. Watt, The commercial products of India. London 1908, p. 1106.
The distillation of the oil is rendered difficult because of its sparing volatility, hence it is conducted mostly in Europe. In India the distillation is frequently carried out with sandalwood or sandalwood oil. This oil is but seldom exported. However, during recent decades considerable quantities of oil have been exported from Reunion. The oil distilled there differs somewhat from the oil distilled in Europe. This difference is due in part to the fresher condition of the root distilled in Reunion, partly to the method of distillation1).
In Europe the dry roots yield, according to their quality, from 0,4 to 1,0 p. c, rarely up to 2 p. c. of oil2).
From fresh, crushed Philippine roots Bacon3) obtained a yield of 1,09 p.c, from crushed, fresh roots only 0,3 p.c. of oil.
Properties. A distinction should be made between the viscid, dark yellow to dark brown, dense oils from dry roots and the less viscid and less dense oils from fresh roots. To the second class belongs e. g. the vetiver oil from Reunion. However, the odor of this oil is not as intense, neither is it as persistent as that of the European distilled oil, hence it is not as highly esteemed as the oil from the dry root. In consequence a lower price is paid therefor.
The properties of the oil distilled in Europe, hence from the dried roots, are as follows: d15o 1,015 to 1,04; aD+ 25 to + 37°; nD20o1,522 to 1,527; A. V.27 to 65; E. V. 9,8 to 23; E. V. after acetylation 130 to 158; soluble in 1 to 2 vols. of 80 p.c. alcohol, additional alcohol causing turbidity.
In connection with Reunion oils the following constants have been observed: d15o0,990 to 1,020; aD+22 to+37°; nD20o1,515 to 1,527; A. V. 4,5 to 17; E. V. 5 to 20; E. V. after acetylation 124 to 145; soluble in 1 to 2 vols. of 80 p.c. alcohol, additional alcohol occasionally causing turbidity.
1.) E.Theulier, Bull. Soc. chim. III. 25 (1901), 454. 2) Report of Schimmel & Co. April 1907, 102. 3) Loc. cit.
d15o 0,980, and has the empirical formula C9H140. The other alcohol has the formula C11 H18 O, boils between 174 and 176° (10 mm.), d15o l,02.
An oil obtained from the Fiji islands1) was dark green in color and revealed the following constants: d15/15o 1,0298; S. V. 35,3; soluble in 80 p. c. alcohol, at first to a clear solution which becomes turbid after the addition of 25 vols, and more. Roots imported from the Seychelles yielded 0,482 p. c. of oil of which 0,072 p.c. were separated from the aqueous distillate. The examination of the oil obtained directly (0,41 p.c.) yielded the following results: d15.1,0282; aD20„ + 27 °; A. V. 55,9; S. V. 67,3; E. V. 11,4; soluble in 1 vol. and more of 80 p. c. alcohol. The oil possessed a deep golden-brown color and was viscid. The oil separated from the aqueous distillate possessed similar properties, but had a somewhat fainter odor.