Pterodon emarginatus Vogel, Fabaceae, is a tree species commonly known as "sucupira-branca". It is a popular medicinal plant in the Brazilian cerrado (Savanna). This study investigates the chemical variability of the essential oils from fruits of P. emarginatus. The fruits were collected from five sites in the Brazilian Cerrado and their essential oils were analyzed by GC/MS. The results obtained by Principal Component and Cluster Analysis identified two groups: cluster I containing β-caryophyllene and δ-elemene and cluster II containing α-copaene, β-cubebene, allo-aromadendrene, α-cubebene and γ-muurulene. The Canonical Discriminant Analysis was used to differentiate between clusters on the basis of essential oil composition. The results showed high variability in the composition of the essential oils from fruits of P. emarginatus, contributing to studies of domestication of this species.

Com o objetivo de avaliar o comportamento agronômico, o potencial de rendimento de óleo essencial e identificar os quimiotipos de 16 acessos de Lippa alba (erva cidreira) da coleção da Universidade de Brasília foi conduzido um experimento de campo em Latossolo Vermelho, sob irrigação por gotejamento na região do Cerrado do Distrito Federal. Foram avaliados a época de florescimento, hábito de crescimento, área foliar, comprimento da haste, massa fresca de folhas e hastes, massa foliar seca, teor e rendimento de óleo essencial e perfil aromático. O óleo essencial foi extraído por hidrodestilação em aparelho de Clevenger modificado e os constituintes identificados e quantificados através de cromatografia em fase gasosa acoplada a espectrometria de massas. O delineamento experimental utilizado foi de blocos ao acaso, com três repetições, contendo três plantas úteis por parcela. Foram identificados os quimiotipos citral-limoneno, citral-mirceno, limoneno-carvona, citral, linalol, mirceno e linalol-limoneno. Os acessos apresentaram teores máximos de linalol de 89,8% (L.16); mirceno de 47,6% (L.37); limoneno de 36,0%, carvona de 46,9% (L.27) e citral de 56,7% (L.17). Os genótipos com maiores áreas foliares e maiores comprimentos de hastes tenderam a apresentar maiores teores de óleo e maior concentração de linalol. A concentração de óleo foi inversamente proporcional à produção de massa foliar seca. Os acessos que apresentaram os maiores rendimentos dos compostos majoritários do óleo essencial foram: L.16 (0,77 g pl-1), como fonte potencial para a produção de linalol; L.17 (0,17 g pl-1), como fonte de mirceno; L. 27 (0,17 g pl-1), como fonte de limoneno e de carvona (0,21 g pl-1) e L.38 (0,24 g pl-1), como fonte de citral.

The main objective of this work was to describe the essential oil profile of 16 genotypes of Lippia alba from the germplasm collection of the Universidade de Brasília and to analyze its potential of production. A field assay was carried out in the rural area of Distrito Federal and the following parameters were analyzed: flowering period, growing habit, foliar area, length of the main branch, fresh and dry weight of the biomass (leaves and branches), essential oil content and profile of the constituent volatile oils. Essential oil was extracted using a modified Clevenger apparatus and the constituent volatile oils were analyzed by gas chromatography and GC/MS. The experimental design was randomized blocks with three plants per plot. The following chemotypes were reported: citral-limonene, citral-myrcene, limonene-carvone, citral, linalool, myrcene and linalool-limonene. Higher levels of linalool were found in genotype L.16 (89.8%); myrcene in L.37 (47.6%); limonene in L.27 (36.0%); carvone in L.27 (46.9%) and citral in L.17 (56.7%). The genotypes with the highest leaf area and leaf length of the main branch seem to be correlated with the best yield of essential oil and the higher level of linalool. The yield of essential oil was inversely proportional to the dry weight of biomass. The accessions which presented the highest average yield of the major essential constituent oils were: L.16 (0.77 g pl-1) as a source of raw material for linalool production; L.17 (0.17 g pl-1) as source of myrcene; L. 27 as source of limonene (0.17 g pl-1) and carvone (0.21 g pl-1); and L.38 (0.24 g pl-1) as a citral source.

Este artigo descreve a caracterização por CLAE-DAD-EM/EM e CLAE-DEC dos perfis de metabólitos secundários de extratos das folhas de Lychnophora ericoides Mart. de diferentes procedências e suas propriedades citotóxicas e antioxidantes. Extratos foliares de populações representando sete diferentes localidades foram avaliados quanto à atividade antioxidante pelo sistema DPPH e à atividade citotóxica em três linhagens tumorais. Os extratos foram eletroquimicamente caracterizados por CLAE-DEC e seus metabólitos secundários majoritários foram identificados por CLAE-DAD-EM e CLAE-DAD-EM/EM. Um metabolismo secundário defensivo amplificado, juntamente com as mais altas bioatividades antioxidantes e citotóxicas, foi encontrado para as plantas coletadas na interface entre dois tipos de vegetação. Estes resultados fornecem apoio adicional para a hipótese de que plantas ocorrendo na interface entre dois ecossistemas podem ser estimuladas a amplificar sua produção e armazenamento de metabólitos secundários defensivos, devido ao maior número de influências ambientais.

This paper reports HPLC-DAD-MS/MS and HPLC-ECD characterisation of secondary metabolite profiles of Lychnophora ericoides Mart. leaf extracts from different provenances and their cytotoxic and antioxidant properties. Leaf extracts from populations representing seven different locations were evaluated for antioxidant activity by the DPPH radical scavenging system and activity towards cellular growth in three tumor cell lines. The extracts were electrochemically analysed by HPLC-ECD and their main secondary metabolites were identified by HPLC-DAD-MS and HPLC-DAD-MS/MS. An amplified defensive secondary chemistry, together with maximal cytotoxic and antioxidant bioactivities, were found for plants collected at the interface between two types of forest. These findings furnish additional support for the hypothesis that plants occurring at the interface between two forests ecosystems might be stimulated to amplify their own production and storage of defensive secondary metabolites due to the greater number of environmental influences.

The ecdysteroid 20-hydroxyecdysone (20E) is a steroid hormone found in insects and few plants. To analyze its temporal and spatial distribution in Pfaffia glomerata (Amaranthaceae), we selected among 71 accessions, the accession 13 which showed the highest root 20E total quantity (1.48 g/plant root). The 20E was constantly detected in flowers, leaves, stems, and roots, but its percentage was variable throughout its development. The highest 20E percentage was found in flowers (0.82%), roots (0.66%), leaves (0.60%), and stems (0.24%). While stems showed the least variable 20E percentage (0.13% - 0.24%), followed by roots (0.42% - 0.66%), and flowers (0.47% - 0.82%). Leaves showed the greatest 20E percentage variation (0.21% - 0.60%). The stem and leaves 20E total amount remained constant, showing a little variation while root 20E total amount increased over time, suggesting that 20E may be accumulated in roots. These findings suggest that 20E has tissue specific functions in plant and may have ecological significance since uncoordinated pulses of 20E are often lethal to insects.

A variação na composição química do óleo essencial das folhas em três populações silvestres de Lychnophora ericoides, com ou sem odor, indicou a presença de dois grupos de óleos em relação ao odor das amostras. O primeiro incluiu amostras de odor aromático contendo altas percentagens de α-bisabolol (34 ± 23%) e o-cimeno (8,4 ± 6,9%). No grupo II, as amostras não apresentaram qualquer odor e os constituintes majoritários foram o óxido de cariofileno (11 ± 9%) e o δ-elemeno (5,7 ± 6,9%). Em todas as populações estudadas co-existem os dois tipos de óleos, embora a maioria das amostras aromáticas provenientes do Parque Estadual da Serra de Caldas Novas se diferenciem quimicamente daquelas do Parque Nacional de Brasília e de Santo Antônio do Descoberto. As variações químicas sugerem claramente, além da influência geográfica, diferenças genéticas entre indivíduos nas populações. O alto conteúdo de α-bisabolol suporta o uso medicinal folclórico de arnica como antiinflamatório.

Variations in the composition of the leaf essential oils of wild Lychnophora ericoides, with and without scent, which were grown in three sampling sites, were examined by GC-MS. Results were submitted to principal component and cluster analysis which allowed for two groups of essential oils to be distinguished with regard to scent: cluster I with specimens exhibiting an aromatic scent and containing a high percentage of α-bisabolol (34 ± 23%) and o-cymene (8.4 ± 6.9%); cluster II with specimens without any scent and characterised by a high percentage of caryophyllene oxide (11 ± 9%) and δ-elemene (5.7 ± 6.9%). The two types of oil coexist in all the populations under study, although patterns of aromatic samples deriving from Caldas Novas' State Park reveal chemical differences in relation to the samples from Brasília's National Park and Santo Antônio do Descoberto. Such chemical variations clearly suggest, apart from a geographical influence, genetic differences between individuals in the populations. The high content of α-bisabolol supports the folk medicinal use of arnica as anti-inflammatory.