Banca de DEFESA: ÉDER RAMIN DE OLIVEIRA

Uma banca de DEFESA de MESTRADO foi cadastrada pelo programa.
STUDENT : ÉDER RAMIN DE OLIVEIRA
DATE: 25/05/2023
TIME: 14:00
LOCAL: On line
TITLE:

NEW METHODOLOGY FOR THE DEVELOPMENT OF BIODEGRADABLE BIOLOGICAL CONTROL AGENTS WITH APPLICATION IN AGRICULTURE

PAGES: 149
BIG AREA: Outra
AREA: Multidisciplinar
SUMMARY:

The application of essential oils and rhizobacteria in the biological control of pathogens as sustainable alternatives to the use of chemical pesticides has been a great challenge. In this way, the present work has as a final objective the development of capsules containing essential oil and rhizobacteria, as a sustainable alternative to chemical pesticides already widely spread, such as spray chilling and jet. The methodology employed is a mixture of spray chilling and jet techniques, where the capsules produced should have diameters smaller than 150.0 µm. Initially, several essential oils were tested against the pathogenic fungi Botrytis cinerea, Colletotrichum gloeosporioides and Corynespora cassiicola, and the rhizobacterium Bacillus amyloliquefaciens 1304. The essential oil of cassia cinnamon, whose main compound identified by GC-MS is trans-cinnamaldehyde (82.2%), showed significant results due to its fungicidal power, eliminating all pathogenic fungi at concentrations up to 0.05% (v/v). Against B. amyloliquefaciens 1304, the inhibition occurred at values of 12.5% (v/v). B. amyloliquefaciens exerts an antagonistic effect against the pathogenic fungi B. cinerea (83.4%), C. gloeosporioides (59.2%), and C. cassiicola (56.1%).  For the capsules, calcium alginate was used as the wall material, average diameters (D90) were obtained between 44.9 µm and between 98.6 µm for capsules containing cinnamon essential oil, of 19.5 µm and 66.0 µm for capsules containing the bacterium. FTIR-ATR analysis was able to reveal possible interactions between calcium alginate and essential oil, while TGA and its DTGs analyses recorded increases in the degradation onset temperatures of cross-linked capsules loaded with cinnamon essential oil up to 285.2 °C. Capsules containing B. amyloliquefaciens obtained this same thermal event at 275.7 °C, and all formulations were more resistant to the action of heating compared to non-crosslinked sodium alginate. The encapsulation allowed the antimicrobial action, offering control over the pathogens B. cinerea, C. gloeosporioides and C. cassiicola in up to 5 days. Thus, the present work presents new methodologies for obtaining polymeric capsules containing different active principles, through external gelation of sodium alginate. The methodologies were able to produce results comparable to others presented in the literature, with relatively simpler equipment, reducing costs at the bench level, withstanding for 4 days in accelerated stability tests without offering phytotoxicity.

COMMITTEE MEMBERS:
Presidente - Interno ao Programa - 1671275 - DERVAL DOS SANTOS ROSA
Membro Titular - Examinador(a) Interno ao Programa - 1760410 - JEVERSON TEODORO ARANTES JUNIOR
Membro Titular - Examinador(a) Externo à Instituição - GILSON PAULO MANFIO
Membro Suplente - Examinador(a) Interno ao Programa - 2605463 - JOSE ANTONIO SOUZA
Membro Suplente - Examinador(a) Externo à Instituição - DANIELLA REGINA MULINARI - UERJ