Banca de QUALIFICAÇÃO: TÚLIO ALEXANDRE FREIRE DA SILVA
Uma banca de QUALIFICAÇÃO de DOUTORADO foi cadastrada pelo programa.STUDENT : TÚLIO ALEXANDRE FREIRE DA SILVA
DATE: 27/09/2023
TIME: 09:00
LOCAL: Sala 101, Departamento de biologia UFRPE
TITLE:
Effects of the use of oxygen carriers and delta-endotoxin microencapsulation on the antimicrobial activity against the etiological agents of caprine mastitis
KEY WORDS:
Antimicrobials, goat mastitis, oxygen vectors, nanotechnology
PAGES: 92
BIG AREA: Ciências Agrárias
AREA: Medicina Veterinária
SUBÁREA: Medicina Veterinária Preventiva
SPECIALTY: Doenças Infecciosas de Animais
SUMMARY:
Caprine mastitis is a common disease in goat herds and has significant economic implications due to the reduction in milk production and the costs associated with disease treatment and management. Additionally, caprine mastitis can affect milk quality, making it unsuitable for human consumption. Bacteria such as Staphylococcus aureus, Streptococcus agalactiae, and Escherichia coli are often responsible for mastitis cases. The administration of specific antibiotics targeting the infecting pathogen is the standard treatment. However, studies have shown that the bacteria causing caprine mastitis are exhibiting resistance genes to antibiotics. Consequently, various studies are being conducted to find substances with antimicrobial activity against the causative agents of caprine mastitis. Among these substances, Bacillus thuringiensis delta-endotoxins stand out. Delta-endotoxins are primarily used as bioinsecticides in agriculture, but some studies have shown that they also possess antimicrobial activity. One of the factors that affect both the production and toxicity of delta-endotoxins is oxygenation. In general, high levels of oxygenation imply high toxicity and delta-endotoxin production. However, to achieve such levels, mechanical agitation and aeration must be increased, consequently raising electricity consumption. One solution to this issue is oxygen vectors, substances that enhance oxygen solubility in aqueous media. Therefore, the first objective of this Ph.D. thesis was to evaluate the effect of oxygen carriers on the production of antimicrobial delta-endotoxins. From this study, presented in both Chapter 1 (Research paper) and Chapter 2 (Patent), it was observed that the tested oxygen carriers can increase production and antimicrobial activity. Nevertheless, another issue related to mastitis treatment is the biofilms formed by pathogens, which hinder the penetration of antimicrobial agents. As an alternative, studies have shown that this problem can be addressed through the micro or nanoencapsulation of antimicrobials. Therefore, this was the second aim of the current work, with Chapter 3 presenting a patent related to the encapsulation procedure of antimicrobial delta-endotoxins. However, the results obtained in this study are promising and contribute to the development of both upstream and downstream methods concerning the production and use of delta-endotoxins as antimicrobial agents for the treatment of caprine mastitis.
COMMITTEE MEMBERS:
Interna - MARIA TACIANA CAVALCANTI VIEIRA SOARES
Externa à Instituição - CLARISSE SALOMÉ NOBRE GONÇALVES - UMinho
Externo à Instituição - LEANDRO FRAGOSO LINS
Externa à Instituição - MARCIA NIEVES CARNEIRO DA CUNHA