Limonene fennel

Bitter fennel Foeniculum vulgare MU , subsp. vulgare var. vulgare ( )-Anethole (55-75), fenchone (12-26), limonene (1-5)... 

Approximately 45 constituents have been determined from fennel seed oil (Fig. 12.1), the main constituents being transanethole (60-65%, but up to 90%), fen-chone (2-20%), estragol (methyl chavicol), limonene, camphene, a-pinene and other monoterpenes, fenchyl alcohol and anisalde-hyde. The major compounds in supercritical... 

Many techniques are followed to identify and quantify the components of fennel essential oil. Krizman et al. (2006) developed a headspace-gas chromatography method for analysing the major volatile constituents in fennel fruits and leaves — a-pinene, a-phellandrene, limonene, fenchone, estragole and trans-anethole. 

This is distilled from the fruit of F. dulce, its main constituents being limonene (20-25%), fenchone (7-10%) and transanethole (4—6%). Arctander (1960) placed the oil in the sweet, non-floral, candy-flavoured group. In the USA, the regulatory status generally recognized as safe has been accorded to fennel oil, GRAS 2481, and sweet fennel oil, GRAS 2483. 

In summary, Foeniculum is stated to have three species, F. vulgare (fennel), F. azoricum Mill. (Florence fennel) and F. dulce (sweet fennel). Fennel is widely cultivated, both in its native habitat and elsewhere, for its edible, strongly flavoured leaves and seeds. The flavour is similar to, but milder than, that of anise and star anise. Anethole and fenchone are the major constituents of the solvent extract of seed phenols, free fatty acids, carbohydrates, proteins, vitamins and minerals have been reported in varying proportions. In the mature fruit, up to 95% of the essential oil is located in the fruit, greater amounts being found in the fully ripe fruit. Approximately 45 constituents have been determined from fennel seed oil, the main constituents being frans-anethole, fenchone, estragol (methyl chavicol), limonene, camphene, a-pinene and other monoterpenes, fenchyl alcohol and... 

Fennel oils are composed mainly of phenylpropane derivatives, the different anethol isomers making up 60-80% of the oil, followed by fenchone, a bicyclic monoterpene lactone making up 10-35%, and monoterpene hydrocarbons, mainly limonene, with a content of up to 10%. 

Composition E-anethole (bitter fennel 55-75%, sweet fennel 80-95%), fenchone (bitter fennel 12-25%, sweet fennel below 1%), methyl chavicol (2-6%), limonene, a-pinene, a-phellandrene, cis-anethole and anisic aldehyde. For further constituents see [99,100]. Ravid et al. ]101] employed chirality GC to prove that enantiomerically pure (-i-)-fenchone is present in fennel oil. 

Figure 6. Fennel 1 - a-pinene, 2 - P-myrcene, 3 - limonen, 4 - fenchon, 5 - estragol, 6 - trans-anethol.

Oil of Fennel. Volatile oil from the dried fruit of Foeniculum vulgare Mill., Umbelliferae. Also from the sweet fennel plant (var. duke). Constit 50-60% anethole, —20% fenchone, pinene, limonene. dipentene, phellandrene. 

Fenchane derivatives occur as fenchones and fenchols in several ethereal oils. Oil of fennel, obtained from the dried fruit of Foeniculum vulgare (Umbelliferae), contains up to 20 % (+)-fenchone, and is associated with limonene, phellandrene and a-pinene. (-)-Fenchone is isolated from the tree of life Thuja occidentalis (Cu-pressaceae), which is cultivated as hedges. The dextrorotatory enantiomer of a-fenchol with an endo OH, requested in perfumery, as well as its stereoisomers are found in fresh lemon juice, in oil of turpentine obtained from Pinus palustris (Pina-ceae), in ethereal oils originating from the Lawson white cedar Chamaecyparis lawsoniana (Cupressaceae) and other plant families such as Ferula, Juniperus, and Clausena species... 

Essential oils from oregano herb (0. onite, laurel leaf (Lauras nobili, sage leaf (Salvia fruticosa), fennel fruit (Eoeniculum vulgare), myrtle leaf (JHyrtus communi , and citrus peel (rich in limonene) were mixed and formulated as feed additive after encapsulation. It is marketed in Turkey as poultry feed under the name Herbromix. 

ISO standard 3475 shows character and data for that oil. This oil often is produced not only from the fruits but also from the whole aerial part. Values of cis- and tran -anethole are then reduced in smaller amount. Adulteration with star anise oil can be easily detected. Anise fruit oil does not contain any foeniculin, but star anise oil contains up to 3% (ISO 11016). On the other hand pseudo-isoeugenol-2-methylbutyrate is a component of anise fruit oil (0.3%-2%, ISO 3475) and does not appear in star anise oil. The midratio of cA-anethole to frani -anethole in anise seed oil in relation to star anise oil is 0.3% 0.6%. Synthetic anethole, fennel terpene limonene (80°), and terpineol were used for blending. 

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