Estudo in vitro da atividade antifitopatogênica de oleorresinas de Copaifera spp.e do ácido ent-poliáltico

• Autor(a) principal: Alcantara, Clauber Barbosa de
• Data de Publicação: 2017
• Tipo de documento: Tese
• Idioma: por
• Título da fonte: Repositório do Centro Universitário Braz Cubas
• Texto Completo: https://repositorio.cruzeirodosul.edu.br/handle/123456789/405
• topic: Copaifera; Atividade antibacteriana; Bactérias fitopatogênicas; Oleoresinas; CNPQ::CIENCIAS EXATAS E DA TERRA

The diseases caused by bacteria phytopatogenics in plants are responsible for a significant loss in agricultural production due to their rapid spread, resistance to most synthetic bactericides and contaminated seeds. This study evaluated in vitro the antibacterial activity of oilresins and the respective fixed fractions of five Copaifera species (C. duckei, C. pubiflora, C. paupera, C. multijuga and C. reticulata) and of the ent-polyaltic acid against plant pathogenic bacteria of agricultural interest. The oilresins were collected in different states of the Amazonas from August 2013 to March 2014. The study of dereplication of oilresins was done by CLAE-EM based on the retention time of the chromatographic peaks and their respective spectra of ions products (MS/MS of standards). The fixed fractions were obtained by hydrodistillation of the oilresinsby steam stripping using the Clevenger apparatus. Isolation of entpolyaltic acid from the oilresin of C. duckei started with a vacuum liquid chromatography followed by CLAE analysis of the fractions. Antimicrobial activity was evaluated by the minimum inhibitory concentration (MIC) and minimum bactericide concentration (MBC) by micro dilution in plates. Dereplication of oilresins showed that the main constituents of the non volatile fraction are the terpenic acids. Oleoresins gave promising MIC and MBC values Xanthomonas axonopodis pv. passiflorae (gram-negative) and all gram-positives above 60 μg mL-1 , and to fixed fractions above 30 μgmL-1 , respectively. In contrast, the same was not true for ent-polyaltic acid, which had MIC and MBC values >100 μg mL1 , is not promising for the control of plant pathogenic bacteria evaluated. Promising antibacterial activity was found for phytobacteria Xanthomonas axonopodis pv. passiflorae (gram-negative) and all gram-positives.