[Chemical composition of essential oils from leaves of Helicteres guazumifolia (Sterculiaceae), Piper tuberculatum (Piperaceae), Scoparia dulcis (Arecaceae) and Solanum subinerme (Solanaceae) from Sucre, Venezuela].

Essential oils, biosynthesized and accumulated in aromatic plants, have a wide range of applications in the pharmaceutical health, cosmetics, food and agricultural industry. This study aimed to analyze the secondary metabolites in some plant species in order to contribute to their chemotaxonomy. Leaves from Helicteres guazumifolia, Piper tuberculatum, Scoparia dulcis and Solanum subinerme were collected and their essential oils were obtained by means of hydro-distillation.

[Secondary metabolites, lethality and antimicrobial activity of extracts from three corals and three marine mollusks from Sucre, Venezuela].

The study of biochemical activity of extracts obtained from marine organisms is gaining interest as some have proved to have efficient health or industrial applications. To evaluate lethality and antimicrobial activities, some chemical tests were performed on crude extracts of the octocorals Eunicea sp., Muricea sp.