**9.2 Origin**

Regarding the origin, essential oils are classified as: natural, artificial and synthetic.

The natural EOs are obtained directly from the plant and are not subsequently subjected to any physicochemical or chemical modification, they are expensive and

**75**

trend.

**10. Conclusions**

*Essential Oils in the Development of New Medicinal Products*

development or the time of day when collect the plant.

pounds are present in the essence in a proportion >1 or 0.5%.

the plant where the essence is stored, etc.

which is still a matter of research.

varied in composition. The artificial essences are obtained by enrichment of natural essences with one of its components; they are also prepared by mixtures of several natural essences extracted from different plants as a mixture of essences of rose,

The essence of anise enriched with anethole is an artificial essence. The synthetic essences are mixtures of various products obtained by chemical processes. They are more economical and therefore are widely used in the preparation of substances flavors and flavorings, such as essences of vanilla, lemon, and strawberry.

Essential oils differ in composition and properties of fatty acids or fixed oils,

Because essential oils are a part of the metabolism of plants, their chemical composition varies permanently, modifying the proportions of their constituents or transforming one another, according to the part of the plant the moment of its

that is, each essential oil has its own characteristic mixture of compounds with defined qualitative and quantitative variations. Some may be so simple as cinnamon oil formed in 85% of cinnamaldehyde only, or as complex as jasmine, or chamomile oil with about 130 compounds. A discrimination is made between the compounds contained in an essence, and then we speak of major compounds when the com-

The proportion of the components of the mixture varies from one oil to another,

An essence is in permanent change, not only while it is part of the metabolism of the plant, also after it is extracted; this speaks of a reduced stability and a process of continuous transformation, which generates three stages in the life of an essence: that of maturation or aging, that of stability or useful life and that of decomposition or rancidity, each essence has different times for each stage, including depending on the case, the intermediate stage, where it is considered that the changes do not significantly change the quality of the same, may have a positive or negative

It must be taken into account that given its complex composition, essences have a high probability of undergoing physicochemical modifications by reactions between its own constituents or between these and the medium that includes factors such as: light, temperature, presence of enzymes, the components of the part of

At present, there is a growing demand to explore the vast variety of plant species with biological activities, and their EOs with therapeutic potentials that can help in the alternative treatment of different diseases. But there is also a need to increase awareness of the risks and benefits associated with the medicinal uses of EOs,

Use of plant molecules to treat, for example, infectious diseases is a complementary alternative. The use of EOs in the treatment of malignancy, artemisinin (isolated from *Artemisia annua*) and the anticancer drug, taxol (from *Taxus brevifolia*) are successful examples of the use of these popular medicines, obtained from

these plant species at a cost much smaller than conventional medications.

which are composed of glycerides; and of mineral oils that are composed of

*DOI: http://dx.doi.org/10.5772/intechopen.86572*

geranium and jasmine.

**9.3 Chemical composition**

hydrocarbons.

varied in composition. The artificial essences are obtained by enrichment of natural essences with one of its components; they are also prepared by mixtures of several natural essences extracted from different plants as a mixture of essences of rose, geranium and jasmine.

The essence of anise enriched with anethole is an artificial essence. The synthetic essences are mixtures of various products obtained by chemical processes. They are more economical and therefore are widely used in the preparation of substances flavors and flavorings, such as essences of vanilla, lemon, and strawberry.
