Abstract

SANTOS, Lourdes Campaner dos et al. n-alkanes from Paepalanthus Mart. species (Eriocaulaceae). Acta Bot. Bras. [online]. 2005, vol.19, n.4, pp. 727-732. ISSN 0102-3306.  http://dx.doi.org/10.1590/S0102-33062005000400007.

This work presents the study of nonpolar compounds from plants belonging to the genus Paepalanthus Mart. (Eriocaulaceae). Long-chain linear aliphatic hydrocarbons were identified by GC-FID and GC-MS. The results indicate that Paepalanthus subg. Platycaulon species present a very homogenous profile, with carbon chains of n-alkanes ranging from C₂₅ to C₃₁, most samples presenting higher frequencies of C₂₇ and C₂₉ homologues. Paepalanthus subg. Paepalocephalus species may be distinguished from one another by the distribution of main n-alkanes. P. macrocephalus, subsect. Aphorocaulon species, presents alkanes with odd-carbon numbers and P. denudatus and P. polyanthus, Actinocephalus species, present alkanes with quite distinctive profiles, with many shorter chains and a high frequency of even-carbon number, especially P. polyanthus. The results obtained indicate that the distribution of alkanes can be a useful taxonomic character, as do polar compounds like flavonoid glycosides.

Keywords : Paepalanthus; n-alkanes; GC-FID; GC-MS; chemotaxonomy.