Biotechnology for the production of essential oil
As mentioned in the previous sections, volatiles are natural compounds
that have gained commercial interest due to their flavor and fragrance
properties. The concentration of the most desirable volatiles in
essential oils is very low, about less than 10% (sometimes even less
than 1%) [116]. Plant essential oils are usually obtained through
extraction intact plants [117] such as distillation, solvents,
carbon dioxide, and etc. or by the methods of chemical synthesis. Each
of them has its drawbacks. Chemical synthesis often leads to the
production of a mixture of products that have an approximate natural
flavor quality. Also, this method is not one of the natural and
environmentally friendly [116]. Common extraction methods, in
addition to being costly, have problems such as: weather conditions
including monsoon, drought, or even by volcano, supply shortages,
natural disasters, plant diseases, low yield and etc. [117, 118].
Therefore, due to the limitations and disadvantages of methods of
extraction from intact plants or chemical synthesis, scientists are
trying to move their way to biotechnology methods and make a variety of
plant compounds by microorganisms. In the new biotechnology method which
is a kind of green method, in addition to being environmentally friendly
and no contamination of the process, there are no more problems
mentioned and the product is obtained with very high efficiency and
quality. Production of natural products and volatile through
biotechnology can be an appropriate response to consumer demand in
relation to the consumption of natural products and move towards ”green
processes” and environmentally friendly. One of the major applications
of biotransformation is the production of biotechnology products that
are usually synthesized by chemical methods. Bio-methods include
volatile production through tissue and cell cultures, hairy roots
cultures, culture of microorganisms, biotransformation, metabolic
engineering. Various biotechnological methods for the production of
volatiles are discussed below: