Study of Lippia alba (Mill.) N. E. Brown species and endophytic fungi associated with emphasis on the study of VOCs and biotransformations.

• Autor(a) principal: AiÃrta Cristina Carrà da Silva
• Data de Publicação: 2015
• Tipo de documento: Dissertação
• Idioma: por
• Título da fonte: Biblioteca Digital de Teses e Dissertações da UFC
• Texto Completo: http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=17018
• topic: Lippia alba; Quimiotipos; Compostos volÃteis; ACP; AAH; Fungos endofÃticos; BiotransformaÃÃo; Lippia alba; Chemotypes; Volatile compounds; PCA; HCA; Endophytic fungi; Biotransformation; QUIMICA ORGANICA

This work aimed to isolate and identify endophytic fungi associated to three chemotypes of Lippia alba (Mill.) NE Brown found in Brazilian Northeast and investigate the potential of these fungi in the production of volatile organic compounds (VOCs) and in front biotransformation to organic substrates. In addition, there was a comparative study of the chemical composition of the leaves three chemotypes of L. alba detected both in essential oils obtained by hydrodistillation as the volatile constituents obtained by solid phase microextraction (SPME). The analysis and identification of volatile constituents was performed by gas chromatography coupled to mass spectrometry (GC-MS). The GC-MS data of the samples obtained by hydrodistillation and SPME were subjected to multivariate data analysis, which provided principal component analysis charts (PCA) and hierarchical cluster analysis (HCA), where it was observed that the methodology used obtaining volatile compounds can influence the classification of chemotypes made based on volatile chemically L. alba reported in the literature. The essential oils obtained from the leaves of the three chemotypes of L. alba were tested against nematicide activity, where the essential oil chemotype II had a higher potential nematicide (LD50 = 71.30 ppm). Of the six endophytic fungi isolated from L. alba leaves, only the fungi Colletotrichum sp. (chemotypes I and II) and Scopulariopsis fusca were able to produce VOCs considerably; and wherein the linalool and caryophyllene compounds produced by S. fusca have also been detected in the chemical composition leaves from L. alba chemotype I, where the fungus was isolated. The study of VOCs also pointed a biocatalytic potential for endophytic fungi from L. alba. This potential was investigated using (R)-carvona and (R)-limonene as substrates. Variables such as time and culture medium were investigated in both experiments, and the biotransformation of (R)-carvona by strains of L. alba isolated endophytes resulted in the production of three derivatives, among which one of them has not yet been reported in the literature as a product of biotransformation of carvone. Since the biotransformation of (R) led to the production of limonene nine derivatives among which four have not been reported in the literature as the limonene biotransformation products.