Essential oil constituents of Eclipta prostrata (L.) L. and Vernonia amygdalina Delile

The chemical composition of the essential oils from the leaves and stem bark of Eclipta prostrata (L.) L. and the aerial parts of Vernonia amygdalina Delile (Asteraceae) have been analyzed by capillary gas chromatography (GC) and gas chromatography/mass spectrometry (GC/MS). The investigation led to the identification of 33 and 30 compounds in the oils of the leaves and stem of E. prostrate, respectively, and 40 compounds in the oil of V. amygdalina. While the oil of the leaves of E. prostrata was highly dominated by sesquiterpenoids (89.3%), the stem bark was comprised of sesquiteprenoids (47.7%), straight chain hydrocarbons (25.6%) and monoterpenoids (11.1%). The main constituents of both oils were β-caryophyllene (47.7% and 15.9%) and α-humulene (31.8 and 12.9%) in the leaves and stem, respectively. In addition, ( E)-β-farnesene (10.0%) was also identified in significant amount in the stem bark. On the other hand, the major component of V. amygdalina oil was α-muurolol (45.7%)

Constituents of Cajanus cajan (L.) Millsp., Moringa oleifera Lam., Heliotropium indicum L. and Bidens pilosa L. from Nigeria.

The essential oils of four plant species from Nigeria have been extracted by hydrodistillation and analyzed by GC and GC-MS. The oils of Cajanus cajan were comprised of sesquiterpenes (92.5%, 81.2% and 94.3% respectively in the leaves, stem and seeds). The major compounds identified were α-himachalene (9.0-11.5%), β-himachalene (8.0-11.0%), γ-himachalene (6.9-8.1%), α-humulene (7.1-8.7%) and α-copaene (4.5-5.6%). However, monoterpenoid compounds (81.8%) dominated the oil of Moringa oleifera with an abundance of α-phellandrene (25.2%) and p-cymene (24.9%). On the other hand, aldehydes (52.8%) occurred in the highest amount in Heliotropium indicum, represented by phenylacetaldehyde (22.2%), ( E)-2-nonenal (8.3%) and (E, Z)-2-nonadienal (6.1%), with a significant quantity of hexahydrofarnesylacetone (8.4%). The leaf and stem oils of Bidens pilosa were dominated by sesquiterpenes (82.3% and 59.3%, respectively). The main compounds in the leaf oil were caryophyllene oxide (37.0%), β-caryophyllene (10.5%) and humulene oxide (6.0%), while the stem oils had an abundance of hexahydrofarnesyl acetone (13.4%), δ-cadinene (12.0%) and caryophyllene oxide (11.0%). The observed chemical patterns differ considerably from previous investigations

Analysis of the essential oil of dialium guineense willd

The essential oil of Dialium guineense Willd., grown in Nigeria has been studied by GC and GC/MS. Precocene I (78.8%) was the most singly abundant constituent, with a significant proportion of β-caryophyllene (5.3%). With the exception of valencene and cadalene, all other constituents were present in amount less than 1%. The large content of precocene I in the oil is of taxonomic interest. © 2007, Taylor & Francis Group, LLC. All rights reserved