Banca de DEFESA: ISAAC FILIPE MOREIRA KONIG

Uma banca de DEFESA de DOUTORADO foi cadastrada pelo programa.
DISCENTE: ISAAC FILIPE MOREIRA KONIG
DATA: 02/02/2023
HORA: 08:00
LOCAL: Videoconferência - Google Meet
TÍTULO:

Comparative toxicological prospection of carvacrol and its acetylated derivative in the zebrafish (Danio rerio) and human blood models

PALAVRAS-CHAVES:

Zebrafish; human blood; pesticide; carvacrol acetate; toxicity

PÁGINAS: 115
GRANDE ÁREA: Ciências Agrárias
ÁREA: Agronomia
RESUMO:

The search for natural-based compounds presenting pesticide activity has intensified in
the last decade. However, the lack of comparative toxicological studies is a limiting
factor for their commercialization. The aim of this study was to compare the toxicity of
carvacrol (natural), acetylcarvacrol (semi-synthetic), and fipronil (synthetic) employing
two models: human blood and developing zebrafish (Danio rerio). A series of
concentrations was used to evaluate the effects of these chemicals on hemolytic activity,
erythrocyte morphology, leucocyte viability, and DNA fragmentation. In the zebrafish
model, we assessed survivability, hatchability, malformations, morphometrics,
behavior, mitochondrial bioenergetics, apoptosis, reactive oxygen species as well as
gene expression. Our findings suggest that fipronil presents relatively high toxicity to
human blood cells compared to the other chemicals. Carvacrol at high concentrations
was also toxic, but its use at low concentrations as well as its acetylated derivative
caused reduced damage to blood cells. In the zebrafish model, fipronil exhibited high
acute toxicity following seven days of continuous exposure. It also affected the
expression of genes related to mitochondrial activity, decreased swim bladder surface
area, induced reactive oxygen species, and hypoactivity in the visual motor response
test. Carvacrol and acetylcarvacrol were considerably less toxic to developing zebrafish
compared to fipronil. Acetylation of carvacrol was also responsible for a reduction in
lethality. Taken together, our results show that carvacrol and acetylcarvacrol are safe
replacements for fipronil due to their reduced toxicity in the two models evaluated.
Moreover, chemical modification of a natural compound such as carvacrol would seem
to be a promising alternative to improve its biological activity and reduce its toxicity to
non-target organisms.

MEMBROS DA BANCA:
Presidente - SILVANA MARCUSSI (Membro)
Externo ao Programa - RAFAEL NEODINI REMEDIO - DME/FCS (Membro)
Externo ao Programa - PAULO SERGIO CASTILHO PRETE - DQI/ICN (Suplente)
Externo ao Programa - LUIS DAVID SOLIS MURGAS - DZO/FZMV (Membro)
Externo ao Programa - LUCIANA LOPES SILVA PEREIRA - DQI/ICN (Membro)
Externo à Instituição - LUCAS BRAGANÇA DE CARVALHO - EMBRAPA (Suplente)
Externo à Instituição - LIDIANE ORLANDI - UNILAVRAS (Membro)