Steam distillation essential oils extraction

Steam distillation (essential oil extract on— Fran ki ncense) 100... 

The antioxidant activity of rosemary and sage (leaves and extracts) were most effectively investigated [96,97], Traditional extracts of spices and herbs are obtained by steam distillation (essential oil) or by extracting the botanical with solvents such as alcohol, hexane, or acetone, and removing the solvents by evaporation. The SFE process for production of the inherent natural antioxidants is now the most gentle and effective method [70],... 

Different plants including spearmint (Mentha spicata L ), rosemary (Rosmarinus officinalis L.), dill (Anethum graveolens L.), clary sage (Salvia sclarea L.) and chamomile (Matricaria chamomilla L.) were extracted with CO2 in a high pressure apparatus with 5 L extractor vessel volume. Fractionation of extracts was carried out by releasing the separation pressure at two stages. The extracts were separated into essential oil rich oil and fatty/waxy products. The extracts were collected as separate samples successively in time. The extraction with carbon dioxide was compared to conventional steam distillation (essential oils) and to Soxhlet extraction with hexane (fatty oils). 

Selective extracts obtained in the pressure range around 100 bar contain only small volatile molecules like mono- and sesquiterpenes. Thus they are similar to conventional steam distillates (essential oils). Total extracts recovered in the pressure range around 300 bar contain in addition higher molecular weight lipophilic constituents like fatty oils, resins and waxes and thus are comparable to classical hexane extracts (oleoresins). Consequently supercritical C02-extraction is the only procedure which produces completely different extracts from one and the same raw material on the same equipment. 

Turpentine Oil. The world s largest-volume essential oil, turpentine [8006-64-2] is produced ia many parts of the world. Various species of piaes and balsamiferous woods are used, and several different methods are appHed to obtain the oils. Types of turpentines include dry-distiUed wood turpentine from dry distillation of the chopped woods and roots of pines steam-distilled wood turpentine which is steam-distilled from pine wood or from solvent extracts of the wood and sulfate turpentine, which is a by-product of the production of sulfate ceUulose. From a perfumery standpoint, steam-distilled wood turpentine is the only important turpentine oil. It is rectified to yield pine oil, yellow or white as well as wood spirits of turpentine. Steam-distilled turpentine oil is a water-white mobile Hquid with a refreshing warm-balsamic odor. American turpentine oil contains 25—35% P-pinene (22) and about 50% a-pinene (44). European and East Indian turpentines are rich in a-pinene (44) withHtfle P-pinene (22), and thus are exceUent raw materials... 

Elder flowers are also used in aromatherapy. Rather than making an essential oil by using a steam distillation process to extract the plant s essence, elder is prepared as an absolute by extracting its es-... 

About 120 chemical constituents have been identified in chamomile as secondary metabolites, including 28 terpenoids, 36 flavonoids and 52 additional compounds [4]. A substantial part of drag effects are determined by the essential oil content. Oil is collected from flower heads, either by steam distillation or solvent extraction, for yields of 0.24-1.90% of fresh or dry plant tissue. Among the essential oil constituents the most active are /-/-a-bisabolol and chamazulene. /-/-a-bisabolol has demonstrated anti-inflammatory, antispasmodic, antimicrobial, antiulcer, sedative and CNS activity. Chamazulene is also anti-inflammatory. Topical applications of chamomile preparation have shown benefit in the treatment of eczema, dermatitis and ulceration [5]. 

The odor of a freshly crushed mint leaf, like many plant odors, is due to the presence in the plant of volatile C10 and Ci5 compounds, which are called terpenes. Isolation of these substances from the various parts of plants, even from the wood in some cases, by steam distillation or ether extraction gives what are known as essential oils. These are widely used in perfumery, as food flavorings and medicines, and as solvents. Among the typical essential oils are those obtained from cloves, roses, lavender, citronella, eucalyptus, peppermint, camphor, sandalwood, cedar, and turpentine. Such substances are of interest to us here because, as was pointed out by Wallach in 1887 and reemphasized by Ruzicka in 1935, the components of the essential oils can be regarded as derived from isoprene ... 

The composition of essential oil extracted using SC-C02 has been compared with that of steam-distilled oil by GC-MS (Gopalan et al., 2000b). Out of the 21 components identified, ar-turmerone and turmerone constituted about 60% of the total oil. Analysis of the cyclohexane extract of turmeric by GC-MS coupled with Pseudo Sadtler retention indices reveals a series of saturated and unsaturated fatty acids, along with sesquiterpenes. The fatty acids reported are tetradecanoic... 

Essential oils extracted by water or steam distillation need further purification, especially drying to remove water. Essential oils produced by distillation are limited to compounds with a maximum molecular weight of 225-250. 

The essential oil extracted from the berries by steam distillation is considered to be superior to that from the twigs and leaves. The wood oil is often adulterated with turpentine oil and it is advisable to avoid it for aromatherapy. 

Terpenes are most familiar, at least by odor, as compounds of the so-called essential oils obtained by steam distillation or ether extraction of various plants. Thousands of different terpenes are known. According to the isoprene rule proposed by L. Ruzicka in 1921, they can be considered to arise from head-to-tail joining of simple five-carbon isoprene (2-methyl-1,3-butadiene) units. Terpenes are subdivided into groups depending on the number of isoprene units [9]. For example, monoterpenes are 10-carbon substances biosynthesized from two isoprene units, which can be divided into aliphatic, monocyclic, or bicyclic species Some typical exponents of each monoterpene subgroup are shown in Fig 1... 

Stout tuberous roots of kuth are characterized by a penetrating aroma. Pale yellow or brownish viscous oil or costus oil is obtained from the roots either by steam distillation or through extracting with solvents. The oil contains resinoids (6%), essential oil (1.5%), Saussurine and other alkaloids (0.05%). Biological actions of costus oil are hyposensitive, bronchiodialatoiy, and antiseptic against streptococcus and streptophylococcus (Anonymous, 1976). 

Steam distillation is the main commercial extraction procedure for the production of essential oils from almost any type of plant material. Solvent extraction is also used commercially and yields a resinoid, concrete or absolute according to the solvents and techniques used (see Chapter 4). Both steam distillation and solvent extraction are used on a laboratory scale to produce oils and extracts for analysis. Other methods of extraction, such as supercritical fluid extraction (SFE), which uses supercritical CO2 as the extraction solvent, are now being developed and used on both commercial and laboratory scales. The extracts produced by SFE may contain different materials from the steam-distilled oil because of the solvating power of C02 and the lower extraction temperature, which reduces thermal degradation. The C02 extract may therefore have an odour closer to that of the original material and may contain different fragrant compounds. The choice of extraction procedure depends on the nature and amount of material available, and the qualities desired in the extract. Solvent extraction is better suited to small sample amounts or volatile materi-... 

Qccurance and Identification. An early report of cotton volatile composition by Minyard et al. (44) involved steam distillation of large quantities of leaves and flowers. Major compounds identified included the monoterpenes a-pinene, B-pinene, myrcene, trans-B-ocimene, and limonene ( 4). Several other monoterpene hydrocarbons were also present in low concentration. Since that report, many other terpenes have been identified in cotton essential oil steam distillates and solvent extracts. These compounds include cyclic hydrocarbons such as bisabolene, caryophyllene, copaene and humulene (45-47), the cyclic epoxide caryophyllene oxide (45), cyclic alcohols such as bisabolol, spathulenol, and the aromatic compound... 

Many plants, used as spices or flavor ingredients, are preserved by drying and are ideal matrices for SFE. Once ground to a powder, they have a large surface area and are highly permeable, leading to rapid and efficient extractions. Interest in SFE of plants has principally been for the isolation of essential oils, but recently SFE has also been used to obtain pharmaceutically active compounds. The extraction of the sesquiterpene lactone parthenolide (Fig. 5) from feverfew plants has been described by Smith (30) and Smith and Burford (31). SFE was compared with steam distillation and solvent extraction. While SFE extracted the less-volatile lactones and parthenolide, the steam distillation extracted the volatile terpenes. SFE resulted in incomplete extraction compared... 

Occurrence M. are widely distributed in the plant kingdom. They are obtained by steam distillation or by extraction from crushed plant parts (flowers, leaves, fruits, bark, roots) as essential (= volatile) oils. Since the M. are volatile the amounts of M. emitted by plants in tropical climate zones are considerable. In animal organisms, M. are present only in small amounts as pheromones or defence substances. 

Analysis of plants normally involves a sample preparation stage such as extraction or distillation followed by analysis with gas chromatography or liquid chromatography. The common methods used currently for the isolation of essential oils from natural products are steam distillation and solvent extraction (Ozel Kaymaz, 2004). Losses of some volatile compounds, low extraction efficiency, degradation of xmsaturated compounds through thermal or hydrolytic effects, and toxic solvent residue in the extract may be encountered with these extraction methods. Recently, more efficient extraction methods, such as supercritical fluid extraction (SFE) (Simandi et al., 1998) and accelerated solvent extraction (ASE) (Schafer, 1998) have been used for the isolation of organic compounds from various plants. Subcritical or superheated water extraction (SWE) is non-toxic, readily available, cheap, safe, non-flammable and is a recyclable option. 

Ozel, M.Z. Kaymaz, H (2004) Superheated water extraction, steam distillation and Soxhlet extraction of essential oils of Origanum onites. Analytical and Bioanalytical Chemistry, Vol.379, No.7-8, pp. 1127-1133, ISSN 1618-2650... 

With that pnirpose, vegetable material, from different locations of the Province of Chaco, was collected during the fall. It is during this season that the plant is likely to be used for essential oil extraction. The oil obtained by steam-distillation, independently from non-bloomed plant leaves, from bloomed plant leaves and from flowers of T. minuta. 

The following is a controversial method for essential oil extraction by comparison with classical hydrodistillation methods. In this method, the steam enters the distillation chamber from the top passes through the biomass in the still pot (e.g., the distillation chamber) and percolates into the condenser located below it. Separation of the oil from the aqueous phase occurs in a battery of Florentine asks. It is claimed that this method is very gentle and thus suitable for the treatment of sensitive plants. The biomass is held in the still chamber (e.g., still pot) on a grid that allows easy disposal of the spent plant matter at the completion of the distillation. The whole apparatus is relatively small, distillation times are reduced, and there is less chance of the oil being overheated. It appears that this method is fairly costly and thus likely to be used only for very-high-priced biomass. 

Melaleuca (Myrtaceae) is a native genus of Australia and has found widespread use in medicinal and cosmetic purposes. Essential oils extracted by steam distillation from Melaleuca species are mostly composed of 1,8-cineole, a-pinene, P pinene, and terpinen-4-ol, and they possess antimicrobial and antioxidant properties. Melaleuca oil is a commercial name for oil extracted from leaves of Melaleuca armillaris Sm. with 1,8-cineole (85.8%) as main compound, followed by camphene and a-pinene as constituents also in major concentrations, but to a lower extent. This oil showed a better effect on radical scavenging in the ABTS than in the DPPH assay. Vitamin C was a reference with a higher antioxidant activity for ABTS and DPPH assays (Chabir et al., 2011). 

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