Banca de DEFESA: PAULA BARROSO CRUZ MARCHESINI
Uma banca de DEFESA de DOUTORADO foi cadastrada pelo programa.STUDENT : PAULA BARROSO CRUZ MARCHESINI
DATE: 30/09/2020
TIME: 14:00
LOCAL: Internet Google Meet
TITLE:
Potential of the essential oils of Eremanthus erythropappus (Candeia) and Cinnamomum zeylanicum (Canela) and compounds, α-bisabolol and (E)-cinnamaldehyde, to control the tick of cattle, Rhipicephalus microplus (Acari: Ixodidae).
KEY WORDS:
Cattle tick, sesquiterpene, phenylpropanoid, resistance, energy metabolism.
PAGES: 162
BIG AREA: Ciências Agrárias
AREA: Medicina Veterinária
SUBÁREA: Medicina Veterinária Preventiva
SPECIALTY: Doenças Parasitárias de Animais
SUMMARY:
Compounds of plant origin have been identified as promising in the control of ticks. In chapter 1, the present work aimed at the phytochemical study of essential oils (OEs) from the bark of Cinnamomum zeylanicum (cinnamon) and from the stem of Eremanthus erythropappus (candeia) and evaluation of the tick activity of these OE (s), together with their major isolated compounds and acetylated analog on Rhipicephalus microplus. The results of gas chromatography and mass spectrometry showed the compound (E)-cinnamaldehyde as the major component of the cinnamon OE (86.93%), and α-bisabolol as the main compound of the cinnamon OE (78.71%). The bioassays with the non-fed larvae were performed using the larval pack test at concentrations from 0.31 to 10.0 mg / mL. For engorged females, the immersion test was performed at concentrations of 2.5 to 60.0 mg / mL. With the exception of cinnamyl acetate, which showed low activity for engorged females, it was possible to observe the potential of these compounds of plant origin on R. microplus. In chapter 2, the activity of (E)-cinnamaldehyde and α-bisabolol was investigated on fifty-one populations of R. microplus, with different profiles of resistance to the different active principles that exist commercially. In order to characterize the degree of resistance, ticks based on deltamethrin (Pyrethroid - Butox®), amitraz (Amidine - Triatox®) and chlorfenvinfos (Organophosphate - Supokill®) were used in their commercial concentration in the female immersion test. For the calculation of the LC50 of the larvae translated with the isolated compounds, the larval pack test was performed at concentrations from 0.31 to 10.0 mg / mL. In this stage, tests were also performed with the Porto Alegre strain (POA), a sensitive strain for reference in the calculation of the Resistance Ratio (RR). Based on the results generated, it was not possible to infer a correlation between the efficiency of ticks and the LC50 values of the isolated compounds tested, thus not being observed cross-resistance, indicating that the different results found may be related to existing phenotypic variations between populations. In chapter 3, the lipid profile of the fatty body and eggs of R. microplus engorged females exposed to a concentration of 10.0 mg / mL of (E)-cinnamaldehyde and α-bisabolol were evaluated. To characterize the lipid profile, the techniques of thin layer chromatography and gas chromatography coupled to a mass spectrometer were applied. In addition, an in silico study was carried out in order to know the possible molecular targets of these plant compounds. The results demonstrated changes in the profile of lipids present in the fatty body and eggs of females treated with (E)-cinnamaldehyde and α-bisabolol, showing a possible mechanism of action of these compounds.
BANKING MEMBERS:
Presidente - 058.965.206-03 - CAIO MÁRCIO DE OLIVEIRA MONTEIRO - UFG
Interna - 387922 - VANIA RITA ELIAS PINHEIRO BITTENCOURT
Interna - 072.326.816-90 - MARIANA GUEDES CAMARGO - UFRRJ
Externo à Instituição - RODRIGO LUIZ FABRI - UFJF
Externo à Instituição - WELBER DANIEL ZANETTI LOPES - UFG
Externo à Instituição - WENDELL MARCELO DE SOUZA PERINOTTO - UFRB
Externo à Instituição - JOSE RECK JUNIOR
Externa à Instituição - RENATA SILVA MATOS - UFJF