Desenvolvimento e otimização de um novo sistema para coleta In Situ de compostos orgânicos voláteis de plantas

• Autor(a) principal: Brito, Rafaela de Sousa
• Data de Publicação: 2015
• Tipo de documento: Trabalho de conclusão de curso
• Idioma: por
• Título da fonte: Repositório Institucional da Universidade Federal do Ceará (UFC)
• Texto Completo: http://www.repositorio.ufc.br/handle/riufc/35231
• topic: Semioquímicos; Ecologia Química; COV; Carboxen; GC - MS; Semiochemicals; Chemical Ecology; VOC; Carboxen; GC - MS

This work developed a new methodology for collection of volatile organic compounds (VOCs) having its application been directed at chemical ecology studies, and to do so, made several optimization tests of the method, making use of essential oils chemical composition known as model. The identification of these compounds was made in GC - MS. The methodology consists of the use of polystyrene cartridges, packed with adsorbent Carboxen 569 coupled to a portable vacuum pump used to suck the volatiles under study by means of air flow into the cartridge. The optimized variables in this study were: type of adsorbent collection time, mass of adsorbent, the sample retention time, sample concentration, and reuse cartridge selectivity. Semiochemicals, which are the target molecules of this study, have low molecular weight and are produced by the secondary metabolism of plants, and its study of paramount importance for the comprehension of the interactions between plants and other living things. Were also carried out tests in situ species of African palm Elaeis guineensi Jacq., And American Elaeis oleifera palm (Kunth) Cortés, and interspecific hybrid resulting from a cross between the two species mentioned, in order to relate the attraction of pollinators with the release of specific substances which may be greater or lesser degree, depending on the species. In addition to this application it was also performed the circadian dynamics study of Ocimum basilicum species in order to validate the operation of the system. The result of this study demonstrated the volatile emission behavior during the period from 8:00 to 18:00 with sample collection break every two hours. The overall results obtained were significant, with a total of 55 identified substances, which corresponds to 75.34% of the studied substances essential oils. The analysis method developed in situ showed broad applicability possible to analyze the release profile of these semiochemicals in the studied species. Therefore, the work paves the way for various applications in chemical ecology studies mainly with regard to studies with live plants, so, there is a more faithful approach the reality of the metabolic mechanisms involved in plant - environment relationships.