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Lippia origanoides Kunth. is a medicinal shrub native to some countries in South America, Central America and the Caribbean. This study aims to investigate the chemical composition of the essential oil and the genetic diversity of a natural population of Lippia origanoides in two seasons. Leaf samples were collected from 30 individuals in the dry and rainy seasons. The essential oil was extracted into a Clevenger apparatus and analyzed by gas chromatography coupled to mass spectrometry (GC-MS). The relative quantification of thymol and carvacrol was performed by gas chromatography coupled to a flame ionization detector (GC-FID). Multivariate analysis was used to evaluate the genetic divergence between plants. Carvacrol was the major compound found in most plants for both seasons. In the rainy season, plant 15 presented thymol as the major compound, and plants 16, 27, 28 and 29 presented camphor as the major compound. In the dry season, thymol remained the main compound of plant 15 and camphor remained the main compound of plants 16, 28 and 29; however, plant 27 presented carvacrol as the main compound in this season. After carvacrol, the compounds with the highest content were -terpinene, p-cymene and methyl-ether-thymol. Of the 30 plants studied, only five differed in their chemical composition, showing some degree of stability in relation to the dry and rainy seasons. There was no variation in the main compounds between the two seasons, but there was chemical diversity among the main compounds. Tocher grouping revealed five distinct groups, with group 1 including most of the plants in both dry and rainy seasons, indicating that the time of year evaluated did not significantly interfere with the essential oil composition of most plants. [ABSTRACT FROM AUTHOR]

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The article studies essential oil extracted from medicinal plant Lippia origanoides for its antimicrobial activity and toxicity using team-dragging distillation, chromatography and mass spectrometry. The compounds carvacrol, o-cymene, and thymol mythyl ether were identified. Results showed that the essential oil has antimicrobial effects against Escherichia coli, Staphylococcus aureus, and Salmonella cholerasuis microorganisms. Its chronic toxic effects in rats were also studied.

Background: The complex network of direct and indirect relationships determines not only the species abundances but also the community characteristics such as diversity and stability. In this context, seed predation is a direct interaction that affects the reproductive success of the plant. For Acrocomia aculeata, the seed predation by Pachymerus cardo and Speciomerus revoili in post-dispersal may destroy more than 70% of the propagules and is influenced by the herbivory of the fruits during pre-dispersal. Fruits of plants with a higher level of herbivory during pre-dispersal are less attacked by predators in post-dispersal. We proposed a hypothesis that describes this interaction as an indirect defense mediated by fungi in a multitrophic interaction. As explanations, we proposed the predictions: i) injuries caused by herbivores in the fruits of A. aculeata favor fungal colonization and ii) the colonization of A. acuelata fruit by decomposing fungi reduces the selection of the egg-laying site by predator. Methodology/Principal Findings: For prediction (i), differences in the fungal colonization in fruits with an intact or damaged epicarp were evaluated in fruits exposed in the field. For prediction (ii), we performed fruit observations in the field to determine the number of eggs of P. cardo and/or S. revoili per fruit and the amount of fungal colonization in the fruits. In another experiment, in the laboratory, we use P. cardo females in a triple-choice protocol. Each insect to choose one of the three options: healthy fruits, fruits with fungus, or an empty pot. The proposed hypothesis was corroborated. Fruits with injuries in the epicarp had a higher fungal colonization, and fruits colonized by fungi were less attractive for egg-laying by seed predators. Conclusion/Significance: This study emphasizes the importance of exploring the networks of interactions between multitrophic systems to understand the dynamics and maintenance of natural populations. [ABSTRACT FROM AUTHOR]

Lippia rotundifolia is an aromatic species, native and endemic to rocky fields, which are isolated by small mountains. It is little known about their chemical composition. Because of that we aimed to study the chemical diversity of volatiles released from rosemary leaves (Lippia rotundifolia Cham.) coming from 11 populations of the Minas Gerais, Brazil. The material for chemical analysis was obtained from the accessions in the active germplasm bank of the Instituto de Ciências agrárias of the Universidade Federal de Minas Gerais. A total of 67 compounds were detected by HS-CG-MS. Most volatiles were detected in the São Gonçalo do Rio das Pedras accession, with 40 compounds, whereas in the Santana do Riacho accession only 5 compounds were detected. Volatiles myrcene, linalool and caryophyllene were detected in the majority of the accessions. We concluded that Lippia rotundifolia presents high chemical variability. The volatiles mircene, linalool and caryophyllene are the most frequent, detected in most of the accessions. Due to some accession to present predominance of monoterpenes, others sesquiterpenes, studies of molecular analysis are necessary for associate the chemotypes, since environmental variation influence the gene expression of the secondary metabolites.

A gram-positive bacterium, denominated CFA-06, was isolated from Brazilian petroleum in the Campos Basin and is responsible for the degradation of aromatic compounds and petroleum aromatic fractions. The CFA-06 strain was identified as Bacillus safensis using the 16S rRNA and gyrase B sequence. Enzymatic assays revealed the presence of two oxidoreductases: a catalase and a new oxidoreductase. The oxidoreductases were enzymatically digested and analyzed via ESI-LTQ-Orbitrap mass spectrometry. The mass data revealed a novel oxidoreductase (named BsPMO) containing 224 amino acids and 89% homology with a hypothetic protein from B. safensis (CFA-06) and a catalase (named BsCat) with 491 amino acids and 60% similarity with the catalase from Bacillus pumilus (SAFR-032). The new protein BsPMO contains iron atom(s) and shows catalytic activity toward a monooxygenase fluorogenic probe in the presence of cofactors (NADH, NADPH and NAD). This study enhances our knowledge of the biodegradation process of petroleum by B. safensis .