Volatile oils INDEX

A large number of pharmaceutical substances such as volatile oils, namely peppermint oil, lemon oil, aniseed oil have a definite range of refractive index. Based on this physical characteristic it is possible to ascertain the purity of this volatile oil precisely and accurately. 

The physical characters of greatest importance in the examination of the volatile oils are, besides appearance and odour specific gravity, rotatory power, refractive index, solidifying point, behaviour on distillation, and solubility see sections 1-7). The components most often requiring estimation are esters, alcohols, aldehydes, ketones, phenols (see sections 8-11), and the most common adulterants to be looked for are alcohol,... 

The large cardamom pericarp (husk) yielded 0.18% volatile oil by the Clevenger hydrodistillation method. This oil was analysed for physical parameters, e.g. specific gravity (0.9148), refractive index (1.4733) and optical rotation (-7.700). The volatile oil was subjected to GC-MS analysis and 37 compounds were identified, constituting > 98% of the total oil. The major compounds characterized were 1,8-cineole (38.7%), [3-pinene (13.6%), a-terpineol (12.6%), spathulenol (8.3%), 4-terpineol (4.5%), ger-macrene D (3.0%), a-pinene (2.8%) and (3-selinene (2.7%). GC and GC-MS data revealed that 1,8-cineole content was less than 50% when compared with the seed oil. Table 4.5 shows the major constituents separated by GC-MS (Rout et al., 2003). Figure 4.1 gives the structures of the major chemical components in the volatile oil from seeds. 

The pericarp (husk) of large cardamom yielded 0.18% volatile oil by the Clevenger hydrodistillation method. This oil was analysed for physical parameters, e.g. specific gravity (0.9148), refractive index (1.4733) and optical rotation (-7.700). 

In India, small seeds generally had higher oil content than larger seeds and the main characteristics were specific gravity (15°C), 0.9304 refractive index (15°C), 1.4795 optical rotation, +35° saponification value, 181.2 iodine value (Wijs), 99 unsaponified material, 3.7%. The expressed oil is classified as semi-drying and is a source of lauric and adipic acids (Weiss, 2002). Table 12.4 gives the average physico-chemical properties of fennel volatile oil. 

The refractive index of a transparent substance is the ratio of the velocity of light in air to its velocity in that material under like conditions. It is equal to the ratio of the sine of the angle of incidence made by a ray in air to the sine of the angle of refraction made by the ray in the material being tested. The refractive index values specified in this Codex are for the D line of sodium (589 nm) unless otherwise specified. The determination should be made at the temperature specified in the individual monograph, or at 25° if no temperature is specified. This physical constant is used as a means for identification of, and detection of impurities in, volatile oils and other liquid substances. The Abbe refractometer, or other refractometers of equal or greater accuracy, may be employed at the discretion of the operator. 

PROP Volatile oil from steam distillation of Pinus Ivestris L. (Fam. Pinaceae) constituted of dipentene, pinene, sylvestrene, cadinene, and bornyl acetate. Yellow liquid penetrating odor. Bp 200-220°, flash p 172°F (CC), d 0.86, refr index 1.473 20°. Sol in fixed oils, mineral oil sltiy sol in propylene glycol insol in glycerin. 

PROP Volatile oil from steam distillation of fresh flowers of Rosa gallica L. and Rosa Damascena Mill, and varieties of these species (Fam. Rosaceae). Colorless to yellow Kquid odor and taste of rose. D 0.848-0.863 30°/15°, refr index 1.457 30°. 

Contains spigeline, resins, tannin, and volatile oils. Still listed as an anthelmintics in The Merck Index, p. 8900 and PDR for Herbal Medicines, p. 1155. jSeveral studies support its use in this regard. See Mowrey, Vaiidation ofHerbai Medicine, p. 240 and PDR forHerbai Medicines, pp. 672-673. 

Properties Colorless liquid sweetish, distinctive odor. Vapor 5.3 times heavier than air, d 1.585 (25/ 4C), bp76.74C, fp-23.0C, refr index 1.4607 (20C), vap press 91.3 mm Hg (20C), wt/gal 13.22 lb (25C), flash p none. Miscible with alcohol, ether, chloroform, benzene, solvent naphtha, and most of the fixed and volatile oils insoluble in water. Noncombustible. 

Properties Colorless, highly refractive, heavy, volatile liquid characteristic odor sweet taste. D 1.485 (20/20C), bp 61.2C, fp -63.5C, wt/gal 12.29 lb (25C), refr index 1.4422 (25C). Keep from light. Miscible with alcohol, ether, benzene, carbon disulfide, carbon tetrachloride, fixed and volatile oils shghtly soluble in water. 

Properties Brownish-yellow hquid. D 0.935-0.950 (25C), refr index 1.470-1.473 (40C). Soluble in ether, chloroform, and fixed or volatile oils shghtly soluble in alcohol. 

Properties Colorless or pale-yellow liquid grapelike odor. D 1.132-1.138 (15C), refr index 1.578-1.581 (20C). Soluble in three volumes or more of 80% alcohol, and in benzyl benzoate, diethyl phthalate, fixed oils, mineral oils, and volatile oils insoluble in glycerol slightly soluble in propylene glycol. Congealing p 18C (4% impurity) to 10C (20% impurity). Combustible. 

Properties Colorless, neutral, mobile liquid aromatic ethereal odor saccharin taste. D 1.174 (17C), bp 57-59C, fp -98C, refr index 1.4166 (20C). Soluble in alcohol, ether, fixed and volatile oils very sparingly soluble in water. Combustible. 

Properties Colorless or yellowish liquid, oily becomes brown in air spicy odor and taste. D 1.064—1.070, bp 253.5C, fp —9C, refr index 1.5400-1.5420 (20C), optically inactive. Soluble in alcohol, chloroform, ether, and volatile oils very slightly soluble in water. Combustible. 

Properties Crystals or pale-yellow liquid with bluish fluorescence orange blossom odor. D 1.167-1.175 (15C), refr index 1.5820-1.5840 (20C), bp 135C, mp 23.8C (min). Soluble in five volumes or more of 60% alcohol soluble in fixed oils, propylene glycol, volatile oils slightly soluble in water, mineral oil insoluble in glycerol. Combustible. 

Properties (Commercial grades) Yellow to red oily liquid lardlike odor, darkens on exposure to air. Insoluble in water soluble in alcohol, ether, and most organic solvents, fixed and volatile oils. Solvent for other oils, fatty acids and oil-soluble materials. (Purified grades) Water-white liquid. D 0.895 (20/4C), fp 4C, bp 286C (100 mm Hg), 225C (10 mm Hg), refr index 1.4599 (20C), acid value 196-204, iodine value 83-103, saponification value 196-206, flash p 372 (189C), Combustible. 

Properties Colorless liquid disagreeable taste agreeable odor. D 0.9960 (20/20C), bp 124.5C, mp 12.6C, vap press 25.3 mm Hg (20C), flash p 96F (35.5C) (TOC), sp heat 0.434, refr index 1.40-1.42 (20C), bulk d 8.27 lb/gal (20C), autoign temp 460F (237C). Decomposes on standing stable toward alkalies but slowly decomposed to acetaldehyde when treated with a trace of mineral acid miscible with most organic solvents and volatile oils soluble in water. 

Congealing p 21C, d 0.910-0.913 (25/25C), refr index 1.4475-1.4485 (25C), flash p 295F (146C). Almost insoluble in water miscible with alcohol, chloroform, ether, benzene, and fixed and volatile oils. Combustible. 

Volatile oils (essential oils) are very complex, pleasant smelling, volatile mixtures containing many different compounds. Most of the essential oils have a high refractive index and they are often optically active. These properties are used for their identification and quality control. Essential oils have low water solubility but are readily soluble in organic solvents. Chemically and biosynthetically they are a heterogenous group. 

Gas-Enriched Oils, and of Evaporative Gas-Condensates. It is suggested that the first two regions embrace between them the domain of thermal gas-condensates, insofar as they can be documented by maturity, and of volatile oils often close to their critical points. It is noted in addition that, as shown in Figure 13, oils having saturation pressures (bubble points) greater than 20 MPa also possess elevated values of SF(Pio+), an index of maturity. 

THUJONES Merck Index ii 9326 12 9533] 4-methyi-i-(i-methylethyl)bicyclol3.i.o] hexan-3-onc 3-thujanone absinthol absynthol salvanol tanacetone salviol 3-sabinone c H,sO molecular weight 152.24 c 78.90% h 10.59% o 10.51% Gildemeister, The Volatile Oils, Pharmaceutical Review Publications, Milwaukee, 1900 Artemisia absinthium )... 

Definition Volatile oil from fruit of Pimenta officinalis, contg. eugenol Properties Colorless, yel. or reddish liq., allspice odor and taste becomes darker with age sol. in glac. acetic acid, 1 vol 90% alcohol very si. sol. in water dens. 1.018-1.048 ref. index 1.527-1.540 (20 C)... 

Definition Volatile oil derived from the dried ripe fruit and seeds of Pimpinella anisum, contg. 80-90% anethole, methylchavicol, anisaldehyde Properties Colorless or pale yel. liq. crushed fruit odor, sweet aromatic taste freely sol. in chloroform, ether sol. in DMSO, 95% ethanol, acetone sol. in 3 vols. alcohol sol. < 1 mg/ml in water dens. 0.978-0.988 (25/25 C) m.p. 17 C solid, pt. 15 C min. b.p. 232 C flash pt. 92.8 C ref. index 1.553-1.560... 

Definition Volatile oil from fresh leaves and twigs of Meiaieuca ieucadendron, contg. 50-60% eucalyptol and l-pinene, terpineol, and aldehydes Properties Colorless of yish. liq., agreeable camphor odor, bitter aromatic taste misc. with alcohol, chloroform, ether, CS2 very si. sol. in water sol. in 1 vol. 80% alcohol dens. 0.912-0.925 ref. index 1.4660-1.4710 (20 C)... 

Definition Volatile oil from rhizome of Acorus calamus contg. eugenol, asarone, stearopten Properties Yel. to yish.-brn. vise, liq., aromatic odor, bitter taste misc. with alcohol very si. sol. in water dens. 0.960-0.970 (20/20 C) sapon. no. 16-20 ref. index 1.507-1.515 Toxicology LD50 (oral, rat) 777 mg/kg, (IP, rat) 221 mg/kg poison by IP route mod. toxic by ing. questionable carcinogen experimental tumorigen TSCA listed... 

Definition Volatile oil distilled from the dried ripe fruit of Camm carvi, contg. carvone, d-limonene Properties Colorless to pale yel. clear oily liq., caraway odor and taste darkens and thickens with age sol. in 8 vols. 80% alcohol pract. insol. in water dens. 0.900-0.910 (25/25 C) ref. index 1.485-1.497 (20 C)... 

Definition Volatile oil distilled from the leaves and twigs of Cinnamomum cassia, contg. 80-90% cinnamaldehyde, plus cinnamyl acetate, eugenol Properties YIsh. to brnsh. liq., cinnamon odor, spicy burning taste darkens and thickens on exposure to air sol. in alcohol, fixed oils, propylene glycol si. sol. in water insol. in glycerin, min. oil dens. 1.045-1.063 ref. index 1.6020-1.6060 (20 C)... 

---