Banca de QUALIFICAÇÃO: GENILSA DUARTE DA COSTA OLIVEIRA

Uma banca de QUALIFICAÇÃO de MESTRADO foi cadastrada pelo programa.
DISCENTE : GENILSA DUARTE DA COSTA OLIVEIRA
DATA : 31/08/2017
HORA: 14:00
LOCAL: Sala da Pós-Graduação
TÍTULO:

BIOACTIVE POTENTIAL OF PEPTIDIC EXTRACTS OF ERYTHRINA VELUTINA AND AMBURANA CEARENSIS SEEDS

PALAVRAS-CHAVES:

Cumaru, mulungu, Callosobruchus maculatus, Aedes aegypti, antimicrobial peptides, larvicides

PÁGINAS: 52
GRANDE ÁREA: Ciências Biológicas
ÁREA: Bioquímica
SUBÁREA: Química de Macromoléculas
ESPECIALIDADE: Proteínas
RESUMO:

Plants are constantly subject to abiotic stresses (temperature, salinity, radiation, drought) and biotic (microorganisms, predators, etc.) and in response to these factors have developed constitutive and induced defense mechanisms involving structural and biochemical components such as: (alkaloids, phenols, terpenoids, non-protein amino acids, peptides, and toxic proteins). Leguminous seeds are a rich source of plant defense molecules against pathogens and pests and are therefore a relevant structure in the search for active peptides. The plants of the Caatinga biome are still little known for their potential in bioactive molecules. In this work two species of plants of the caatinga were used to obtain peptide extract from the seeds, Erythrina velutina (mulungu) and Amburana cearensis (cumaru). The seeds were separated into coat and cotyledons, resulting in four different extracts. After extraction of peptides, an SDS-PAGE was performed to analyze the electrophoretic profile that showed the presence of polypeptides from 97 kDa as well as peptides below 18 kDa. The extracts showed inhibitory activity for trypsin, being 99.08% for cotyledon of cumaru; 89.91% for mulungu cotyledon and 68.35% and 63.30% for cumaru and mulungu integument, respectively. When evaluated for fungicide potential for phytopathogenic fungi species A. alternata, M. phaseolina, M. cannoballus and R. solani, none of the extracts were able to inhibit fungal growth. The same extracts also had no antimicrobial potential for E. coli and S. aureus. When evaluating the larvicidal potential of cumaru cotyledon and cotyledon extracts of mulungu in an artificial diet for the Caupi bean bettle, Callosobruchus maculatus, we observed that the cotyledon extract 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 potential against insect vector larvae Aedes aegypti. Coumaru and mulungu cotyledon extracts caused mortality of 100% of L1 larvae at 10 mg/mL concentration after 24 hours of incubation. The extract of mulungu cotyledons presented a mortality of 33% at concentration and 2.5 mg/mL after 48 hours of assay. The 2 mg / mL cumaru coat extract promoted the mortality of 71.66% of the larvae and the coat of mulungu 18.33%. The prospection of bioactivity of peptide extracts showed negative results regarding the antimicrobial potential against phytopathogenic fungi and bacteria. However, of the four peptidic extracts evaluated, only the cotyledon extracts of the two seeds were effective against C. maculatus and the two extracts of cumaru showed higher larvicidal potential for A. aegypti. These findings indicate that the extracts of both seeds are rich sources of molecules, peptides and bioactive proteins with larvicidal potential, but it is still necessary to identify the molecules associated with this activity and its mechanism of action against the two species of insects.

 

MEMBROS DA BANCA:
Presidente - 1549705 - ADRIANA FERREIRA UCHOA
Interno - 1452833 - MARIA CELESTE NUNES DE MELO
Interno - 1715271 - RENATA ANTONACI GAMA