Bioatividades de óleos essenciais de Schinus molle e Cinnamomum cassia e suas combinações

Abstract

This dissertation was divided into two chapters: in the first, the objective was to compare, for the first time, the chemical composition and anti-Xanthomonas citri activities of essential oils from fresh and dried leaves of Schinus molle (OE-FF and OE-FS, respectively). The activity of spathulenol, the main constituent of the oils, against X. citri was also evaluated. The activities were carried out using the broth microdilution method in a 96-well culture. Three main constituents were identified in OE-FF and OE-FS by GC-MS and GC-FID: spathulenol, β-caryophyllene and caryophyllene oxide. With MIC values ranging from 31.25 to 100 µg/mL, they were active against X. citri strains (resistant, tolerant and sensitive to copper). Although the results showed the in vitro potential of OE-FS, OE-FF and spathulenol against X.citri, more in vivo studies are needed to prove their applicability to the biocontrol of citrus canker. The second chapter investigated the chemical composition and antileishmanial and anticandidal activities of essential oils from Schinus molle leaves (OE-SM) and Cinnamomum cassia branch bark (OE-CC) and their mixtures against promastigote forms of Leishmania (Leishmania amazonensis) and the different species of Candida strains, respectively. For this, the essential oils were extracted by hydrodistillation, and their components were identified by gas chromatography coupled to mass spectrometry and gas chromatography with flame ionization detection. The major constituents of OE-SM were spathulenol (20.8%), β-caryophyllene (15.6%) and caryophyllene oxide (10.0%). The OE-CC revealed high concentrations of cinnamaldehyde (60.1%), cinnamyl acetate (20.9%) and methoxycinnamic acid (10.5%). OE-SM (IC50 = 21.45 µg/mL) and OE-CC (IC50 = 23.27 µg/mL) were active against L. amazonensis. The three prepared mixtures exhibited very high leishmanicidal activity, with IC50 values between 3.12 and 7.04 µg/mL. These essential oils OE-SM, OE-CC and their mixtures have been shown to be strong antifungal agents against new strains of Candida, with Minimum Inhibitory Concentration (MIC) values ranging between 31.25 and 250 µg/mL. In short, we conclude that OE-SM, OE-CC and their mixtures are active and can be considered strong candidates to participate in the formulation of drugs with antileishmanial and antifungal action. Keywords: Leishmaniasis, Candidiasis, Citrus canker, Schinus molle, Cinnamomum cassia and Spatulenol.