Banca de DEFESA: GENILSA DUARTE DA COSTA OLIVEIRA
Uma banca de DEFESA de MESTRADO foi cadastrada pelo programa.DISCENTE : GENILSA DUARTE DA COSTA OLIVEIRA
DATA : 29/09/2017
HORA: 09:00
LOCAL: Auditório do Museu de Ciências Morfológicas
TÍTULO:
PROSPECTION OF BIOACTIVITY FOR PEPTIDIC EXTRACTS OF ERYTHRINA VELUTINA AND AMBURANA CEARENSIS
PALAVRAS-CHAVES:
Cumaru, mulungu, antimicrobials, Callosobruchus maculatus, Aedes aegypti, larvicides.
PÁGINAS: 57
GRANDE ÁREA: Ciências Biológicas
ÁREA: Bioquímica
SUBÁREA: Química de Macromoléculas
ESPECIALIDADE: Proteínas
RESUMO:
Plants are constantly subject to environmental stresses, microorganisms and herbivorous insects, which, throughout the evolutionary process, favored the development mechanisms constitutive or induced to guarantee defense to the vegetable. Among the plant defense molecules can be highlighted the antimicrobial peptides, which are already employed in several studies. Antimicrobial peptides are present in several plant organs, but they are found in larger amounts in reserve tissues, such as in legume seeds. These bioactive molecules represent an alternative for the treatment of microbial infections, as well as pest and vector insect control, since the use of antibiotics and conventional insecticides can accelerate or trigger the selection of resistant microorganisms and insects. Thus, this work proposes the prospection of antimicrobial proteins and peptides of Erythrina velutina and Amburana cearensis seeds, two native species of the caatinga biome, which is still little explored as to the biological potential of its species. The seeds of each species were separated into tegument and cotyledons in order to produce four different extracts. To obtain the peptide fraction, two precipitations were performed, one at 90% with ammonium sulfate and the other at 80 ° C / 15 '. Then in a 15% polyacrylamide gel the electrophoretic profile was observed, which showed the presence of polypeptides from 97 kDa as well as peptides below 18 kDa. An assay was performed to evaluate the inhibitory activity of trypsin extracts, 99.08% for cotyledon of cumaru; 89.91% for mulungu cotyledon and 68.35% and 63.30% for cumaru and mulungu coat, respectively. The antimicrobial potential of each phytopathogenic fungus: Alternaria alternata, Macrophomina phaseolina, Monosporascus cannoballus and Rhizotonia solani was evaluated by two methods: disk diffusion (well variation) and dilution in agar. For the bacteria: Escherichia coli and Staphylococus aureus a microdilution was performed. The extracts had no antimicrobial potential for fungi and bacteria, under the evaluation conditions used. When evaluating the larvicidal potential of the cotyledon extracts of cumaru and cotyledon of mulungu in an artificial diet for the Caupi bean beetle, Callosobruchus maculatus, we observed that the extract of cotyledon of cumaru from 1.6% has already been able to reduce the mass of the larvae, compromising its growth and survival. For the cotyledon extracts of mulungu larvae were not observed from the concentration of 0.1%. The extracts were also evaluated for their larvicidal potential for the insect vector Aedes aegypti, where extracts of cumaru cotyledons caused 100% mortality for L1 at concentrations of 10 mg / mL and 5 mg / mL in 24 hours of incubation. The extract of mulungu cotyledons had an average mortality of 33.33% in 48 hours. The 2 mg / mL cumaru coat extract promoted the mortality of 71.66% of the larvae and the coat of mulungu 18.33%. The proteins and peptides obtained did not present antimicrobial activity, but the extracts of both seeds are rich sources of molecules, peptides and bioactive proteins with larvicidal potential, that should be better investigated for identification of the molecule and association with the action mechanism against the two species of insects.
MEMBROS DA BANCA:
Interno - 1549705 - ADRIANA FERREIRA UCHOA
Interno - 1352009 - UMBERTO LAINO FULCO
Externo ao Programa - 2997294 - RICHELE JANAINA ARAUJO MACHADO
Externo à Instituição - DAYANNE LOPES GOMES - UFRN