Extraction Technologies For Medicinal And Aromatic Plants - Unido

EXTRACTION TECHNOLOGIES FOR MEDICINAL AND AROMATIC PLANTS
Special care must be paid to closures and seals. SFE of MAPs
is mostly an extraction operation from solid materials, which is carried out in
batch or semibatch mode. Therefore, extraction vessels need to be pressurized,
depressurized, opened, fi lled, and closed again several times per day.
In order to ensure fast and safe operation procedures and reliable seals,
gaskets like O-rings are useful and closure devices have been specifi cally
designed. Again, the technology needed is already fully developed. We refer
to chapter 4 of the book by Bertucco and Vetter for details. The book also
describes the machinery for moving fl uids under pressure, i.e. pumps and
compressors. We conclude that setting up a laboratory-scale apparatus with
which to perform feasibility studies concerning the possibility of applying
SFE to MAPs is not really an issue, and can be done with a relatively small
capital cost.
However, this does not mean that SFE of MAPs is in itself an
economically convenient operation. An accurate evaluation of production
costs, including both capital and utility costs, must be performed before
scaling up a process whose technical feasibility has been demonstrated at
the laboratory level. Costs are also discussed in the book by Bertucco and
Vetter (chapter 8), but are only indicative. The reader should remember that
capital costs have been steadily decreasing in the last years must be taken
into account.
10.5 SFE Applied to Medicinal and Aromatic
Plants
A large number of MAPs has been considered for possible
extraction by supercritical CO2. The most recent developments suitable to
have industrial relevance are listed in Table 2. These examples illustrate the
great potential of SFE in this fi eld.
Plant name
(part used)
Calendula
offi cinalis
(fl owers)
Table 2: Medicinal and aromatic plants extracted by SFE
Product(s) extracted Reference
Oleoresin Campos et al., 2005, Experimental
data and modeling the supercritical
fl uid extraction of marigold (Calendula
offi cinalis) oleoresin, J Supercritical
Fluids, 34: 163-170
Danielski et al., 2007, Marigold
(Calendula offi cinalis L.) oleoresin:
solubility in SC-CO2 and composition
profi le, Chem Eng Proc, 46: 99–106
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