O. Kayser et al., COMPOSITION OF THE ESSENTIAL OILS OF PELARGONIUM SIDOIDES DC. AND PELARGONIUM RENIFORME CURT, Flavour and fragrance journal, 13(3), 1998, pp. 209-212
The essential oils of Pelargonium sidoides DC. and P. reniforme Curt.
were obtained by hydrodistillation from the leaves of the plants in 0.
52% and 0.71% yields, respectively, related to the dry weight. Their c
omposition was analysed by GLC and GC-MS. About 230 components have be
en detected in each of the Pelargonium oils, of which 102 (P. sidoides
) and 81 (P. reniforme) could be unambiguously identified, accounting
for about 65% and 49% of the total peak area, respectively. For both s
pecies, sesquiterpenes (approximately 60%) were the dominating compone
nts, with caryophyllene (2.3%) and caryophyllene epoxide (13%) as the
most abundant compounds of the sesquiterpene fraction of the oil of P.
sidoides, and the sesquiterpene hydrocarbons delta-selinene (4.2%) an
d delta-cadinene (4.0%) as the main representatives of the oil of P. r
eniforme. Other major groups of the oil of P. sidoides comprised monot
erpenes (16%) and phenylpropanoids (9%), the major compounds of the la
tter group being methyleugenol (4.3%) and elemicin (3.6%). By contrast
, only monoterpenes were found in reasonable amounts (4.7%) in the rel
ated species P. reniforme. Detection of anacardic acids and furan-type
constituents provide a rational explanation for insect deterrency by
Pelargonium species. (C) 1998 John Wiley & Sons, Ltd.