Lychnophora pinaster in endangered campos rupestres: phenolic compounds and population ecogeography.

Lychnophora pinaster, known as arnica-mineira, is endemic to campos rupestres, at risk of extinction. The present study aimed to characterize the ecogeography and phenolic constituents of 11 L. pinaster populations collected in the mesoregions North, Jequitinhonha, Metropolitan of Belo Horizonte and Campos das Vertentes in the state of Minas Gerais, Brazil. Phenolic constituents were identified and quantified by Ultra-high performance liquid chromatography- mass spectrometry. Lychnophora pinaster occurs in sites at high altitude (700 and 1498 m), annual rainfall of up to 1455 m, soils with low fertility and predominantly loamy texture. Therefore, it can be considered tolerant to acidic soils, with low availability of nutrient. The most abundant substances in all populations were vitexin (18 - 1345 ng/g) and chlorogenic acid (60 - 767 ng/g). The 11 populations formed four groups in relation to the phenolic constituents, with group 1 consisting of the populations of the North Mesoregion (GM, OD) and Jetiquinhonha (DIMa), group 2, the Metropolitan of Belo Horizonte (SRM, NLSC, SM, RPS, CTRA), group 3, the North Mesoregion (ODMa and DI), and group 4, the Campos das Vertentes (CC). Among the populations, only those from the Metropolitan of Belo Horizonte showed correlation of soil properties with phenolic constituents.

Essential Oils of Aromatic Plant Species from the Atlantic Rainforest Exhibit Extensive Chemical Diversity and Antimicrobial Activity.

Microbial resistance, caused by the overuse or inadequate application of antibiotics, is a worldwide crisis, increasing the risk of treatment failure and healthcare costs. Plant essential oils (EOs) consist of hydrophobic metabolites with antimicrobial activity. The antimicrobial potential of the chemical diversity of plants from the Atlantic Rainforest remains scarcely characterized. In the current work, we determined the metabolite profile of the EOs from aromatic plants from nine locations and accessed their antimicrobial and biocidal activity by agar diffusion assays, minimum inhibitory concentration, time-kill and cell-component leakage assays. The pharmacokinetic properties of the EO compounds were investigated by in silico tools. More than a hundred metabolites were identified, mainly consisting of sesqui and monoterpenes. Individual plants and botanical families exhibited extensive chemical variations in their EO composition. Probabilistic models demonstrated that qualitative and quantitative differences contribute to chemical diversity, depending on the botanical family. The EOs exhibited antimicrobial biocidal activity against pathogenic bacteria, fungi and multiple predicted pharmacological targets. Our results demonstrate the antimicrobial potential of EOs from rainforest plants, indicate novel macromolecular targets, and contribute to highlighting the chemical diversity of native species.

Chemical Composition and Bactericidal Activity of the Essential Oils of Four Species of Annonaceae Growing in Brazilian Amazon.

A study was conducted to determine the chemical composition and the antibacterial activity of essential oils from Bocageopsis multiflora (Mart.) R.E. Fr., Ephedranthus amazonicus R.E. Fr., Guatteria blepharophylla Mart. and Xylopia aromatica (Lam.) Mart . The essential oils were obtained from the leaves by hydrodistillation and analyzed by GC-FID and GC-MS. The chromatograms showed the predominance of sesquiterpenoids. Spathulenol was the major constituent of oils of B. inultiflora (20.3%), X aromatica (21.5%) and E. amazonicus (16.9%); followed by caryophyllene oxide of G. blepharophylla (55.7%). Other constituents with significant percentages were the sesquiterpenes P-bisabolene (11.9%) in the samples oil of B. multiflora, humulene epoxide 11 (16.3%) -of E. amazonicus, the monoterpenes trans-pinocarveol (10.2%) and dihydrocarveol (11.6%) of X aromatica. The essential oils of X. aromatica and G. blepharophylla showed strong activity against Gram-positive bacteria Streptococcus sanguinis by microdilution method. The antimicrobial activity against Staphylococcus aureus also was detected by G. blepharophylla essential oil.

Floral scent of brazilian Passiflora: five species analised by dynamic headspace.

This study describes for the first time the chemical composition and olfactive description of floral scent from Brazilian Passiflora (Passiflora edulis Sim, Passiflora alata Curtis, Passiflora cincinnata Mast., Passiflora coccinea Aubl. and Passiflora quadrangularis L.). Five species were grown in greenhouse at the Agronomic Institute (IAC), São Paulo, Brazil. Volatile compounds were collected using dynamic headspace. Analyses of scent composition were performed by gas chromatograph coupled to mass spectrometer. Identification of chemical constituents was conducted through of retention index followed by comparative analysis of mass spectra with specialized databases. The olfactive descriptions of floral scent from each species was evaluated for a professional perfumer. High interspecific diversity was found between chemical compositions of floral scent within Passiflora and different bouquets were observed amount the studied species. Mayor constituents were linalool (P. alata), geraniol (P. quadrangularis), 1,4-dimethoxybenzene (P. edulis), benzaldehyde (P. cincinnata) and 2-methyl-3-pentanone (P. coccinea).

Composição química e modulação da resistência bacteriana a drogas do óleo essencial das folhas de Rollinia leptopetala R. E. Fries / Chemical composition and modulation of bacterial drug resistance of the essential oil from the leaves of Rollinia leptopetala R. E. Fries

O óleo essencial das folhasde Rollinia leptopetala foi obtido por hidrodestilação em aparelho de Clevenger e a sua composição química foi analisada através de CG-EM. Com essa técnica, foi possível identificar 22 constituintes em uma mistura complexa demonoterpenos (54,5 por cento) e sesquiterpenos (45,5 por cento). O principal componente encontradonas folhas foi o biciclogermacreno (22,47 por cento). O óleo essencial foi avaliado numa linhagem de Staphylococcus aureus portadora de bomba de efluxo responsável pela resistência norfloxacino. Embora o óleo essencial não tenha apresentado atividade antibacteriana relevante in vitro, ele apresentou atividade moduladora da resistência, ou seja, em combinação com o norfloxacino observou-se uma redução de 4x na concentração inibitória mínima do antibiótico, indicando inibição de bomba de efluxo.

The essential oil from the leaves of Rollinia leptopetala was obtained by hydrodistillation in Clevenger's apparatus and its chemical composition was analyzed by GC-MS. With this technique could be identified 22 constituents in a complex mixture of monoterpenes (54.5 percent) and sesquiterpenes (45.5 percent). The main component found in the leaves was the bicyclogermacrene (22.47 percent). The essential oil was assayed against a strain of Staphylococcus aureus possessing efflux mechanism of resistance to norfloxacin. Although the essential oil did not display relevant antibacterial activity in vitro, it modulated the activity of the norfloxacin, i.e. in combination with the antibiotic it was observed a fourfold reduction in the minimum inhibitory concentration for norfloxacin, indicating inhibition of efflux pump.

Effects of seasonal variation on the central nervous system activity of Ocimum gratissimum L. essential oil.

Ocimum gratissimum L. (Lamiaceae) and other species of the same genus are used as medicines to treat central nervous system (CNS) diseases, commonly encountered in warm regions of the world. The chemical composition of Ocimum gratissimum essential oil varies according to their chemotypes: timol, eugenol or geraniol. In this study, the essential oil type eugenol was extracted by hydrodistillation in each of the four seasons of the year. Activity upon CNS was evaluated in the open-field and rota-rod tests; sleeping time induced by sodium pentobarbital (PBS, 40 mg/kg, intra-peritoneally, i.p.) and anticonvulsant activity against seizures induced by both pentylenetetrazole (PTZ; 85 mg/kg, s.c.) and maximal electroshock (MES, 50 mA, 0.11 s) were determined. Essential oils obtained in each season were effective in increasing the sleeping duration and a preparation obtained in Spring was able to protect animals against tonic seizures induced by electroshock. In each season, eugenol and 1,8-cineole were the most abundant compounds, and in Spring the essential oil presented the greatest relative percentage of sesquiterpenes, suggesting that these compounds could explain the differences observed in the biological activity in essential oils obtained in different seasons of the year.

Phytochemical characterization of essential oil from Ocimum selloi.

Ocimum selloi Benth, a native plant of Brazil, has medicinal uses as anti-diarrheic, antispasmodic and anti-inflammatory product. The yield of essential oils of the inflorescences, containing flowers and seeds, was 0.6%, and the yield of leaves, collected in two different seasons, was 0.25% (June 2000) and 0.20% (January 2001), respectively. The essential oils of the inflorescences and leaves presented as major constituents trans-anethol (41.34%, 45.42%, 58.59%) and methyl chavicol (27.10%, 24.14%, 29.96%).

Phytochemical characterization of essential oil from Ocimum selloi

Ocimum selloi Benth, a native plant of Brazil, has medicinal uses as anti-diarrheic, antispasmodic and anti-inflammatory product. The yield of essential oils of the inflorescences, containing flowers and seeds, was 0.6 percent, and the yield of leaves, collected in two different seasons, was 0.25 percent (June 2000) and 0.20 percent (January 2001), respectively. The essential oils of the inflorescences and leaves presented as major constituents trans-anethol (41.34 percent, 45.42 percent, 58.59 percent) and methyl chavicol (27.10 percent, 24.14 percent, 29.96 percent)