HYDROCARBONS OF NASUTITERMES-ACAJUTLAE AND COMPARISON OF METHODOLOGIES FOR SAMPLING CUTICULAR HYDROCARBONS OF CARIBBEAN TERMITES FOR TAXONOMIC AND ECOLOGICAL-STUDIES
Mi. Haverty et al., HYDROCARBONS OF NASUTITERMES-ACAJUTLAE AND COMPARISON OF METHODOLOGIES FOR SAMPLING CUTICULAR HYDROCARBONS OF CARIBBEAN TERMITES FOR TAXONOMIC AND ECOLOGICAL-STUDIES, Journal of chemical ecology, 22(11), 1996, pp. 2081-2109
Using data from the arboreal nesting Nasutitermes acajutlae (Holmgren)
, we propose standard collection and extraction methodology for charac
terization of cuticular hydrocarbons of termites under field condition
s in the tropics. Specifically, we evaluated: (1) the effect of the du
ration and the number of extractions; (2) the effect of drying termite
s before extraction; (3) the effect of sample size; (4) the effect of
solvents (ethanol versus hexane) on cuticular hydrocarbon profiles. Ol
efins comprise ca. 70% of the cuticular hydrocarbons of N. acajutlae.
Hydrocarbons consist of two distinct groups: early-eluting components,
primarily n-alkanes and methyl-branched alkanes, and late-eluting com
pounds, which consist almost exclusively of unsaturated components wit
h one to six double bonds. Soldiers have more early-eluting compounds
than workers or alates. Nests from the same island had qualitatively s
imilar, but quantitatively dissimilar hydrocarbon mixtures. Brief extr
actions of 300 live workers in 10 mi of hexane for only 20 sec produce
d a hydrocarbon mixture equivalent to a 10-min extraction. Long-term e
xtraction of 300 workers in hexane for two years resulted in different
mixtures of hydrocarbons. Drying workers tended to enhance extraction
of the less abundant unsaturated compounds such as C-41:4, and C-41:5
. A single extraction of a minimum of 100 workers (live or dried), wit
h hexane for 20 sec to 10 min is best; these extraction regimes result
ed in mixtures of hydrocarbons that are quantitatively very similar. F
or quantitative comparisons, extracts from dried samples should not he
compared to those from live samples. Storage in ethanol caused numero
us unidentified, nonhydrocarbon compounds to he extracted either from
the cuticle or from internal tissues.