Emmanoel Vilaça Costa

Antimicrobial and antileishmanial activity of essential oil from the leaves of Annona foetida (Annonaceae)

bicyclogermacrene (35.12%), (E)-caryophyllene (14.19%) and α-copaene (8.19%). The antimicrobial and antileishmanial activities were investigated. The oil showed potent antimicrobial activity against Candida albicans and Rhodococcus equi. The oil also showed significant antileishmanial activity, giving the best results against Leishmania guyanensis. A preliminary cytotoxicity assay for this oil was carried out on hamster and mice (Balb/c) peritoneal macrophages. The results obtained were similar to pentamidine and considered not to be cytotoxic to macrophages.

Spectroscopic investigation, vibrational assignments, HOMO-LUMO, NBO, MEP analysis and molecular docking studies of oxoaporphine alkaloid liriodenine

A combined experimental and theoretical DFT study of the structural, vibrational and electronic properties of liriodenine is presented using B3LYP function with 6-311G (2d, p) basis set. The theoretical geometry optimization data were compared with the X-ray data for a similar structure in the associated literature, showing similar values. In addition, natural bond orbitals (NBOs), HOMO-LUMO energy gap, mapped molecular Electrostatic Potential (MEP) surface calculation, first and second order hyperpolarizabilities were also performed with the same calculation level. Theoretical UV spectrum agreed well with the measured experimental data, with transitions assigned. The molecular electrostatic potential map shows opposite potentials regions that forms hydrogen bonds that stabilize the dimeric form, which were confirmed by the close values related to the CO bond stretching between the dimeric form and the experimental IR spectra (1654cm-1 for the experimental, 1700cm-1 for the dimer form). Calculated HOMO/LUMO gaps shows the excitation energy for Liriodenine, justifying its stability and kinetics reaction. Molecular docking studies with Candida albicans dihydrofolate reductase (DHFR) and Candida albicans secreted aspartic protease (SAP) showed binding free energies values of -8.5 and -8.3kcal/mol, suggesting good affinity between the liriodenine and the target macromolecules.

Antitumour Activity of the Microencapsulation of Annona vepretorum Essential Oil

Annona vepretorum Mart. (Annonaceae), popularly known as ‘bruteira’, has nutritional and medicinal uses. This study investigated the chemical composition and antitumour potential of the essential oil of A. vepretorum leaf alone and complexed with β‐cyclodextrin in a microencapsulation. The essential oil was obtained by hydrodistillation using a Clevenger‐type apparatus and analysed using GC‐MS and GC‐FID. In vitro cytotoxicity of the essential oil and some of its major constituents in tumour cell lines from different histotypes was evaluated using the alamar blue assay. Furthermore, the in vivo efficacy of essential oil was demonstrated in mice inoculated with B16‐F10 mouse melanoma. The essential oil included bicyclogermacrene (35.71%), spathulenol (18.89%), (E)‐β‐ocimene (12.46%), α‐phellandrene (8.08%), o‐cymene (6.24%), germacrene D (3.27%) and α‐pinene (2.18%) as major constituents. The essential oil and spathulenol exhibited promising cytotoxicity. In vivo tumour growth was inhibited by the treatment with the essential oil (inhibition of 34.46%). Importantly, microencapsulation of the essential oil increased in vivo tumour growth inhibition (inhibition of 62.66%).

CHEMICAL CONSTITUENTS FROM THE STEM BARK OF Annona pickelii (Annonaceae)

The phytochemical investigation of the stem bark of Annona pickelii yielded four steroids (β-sitostenone, β-sitosterol, stigmasterol and campesterol), three lignans (eudesmin, magnolin and yangambin), twelve alkaloids (liriodenine, lysicamine, atherospermidine, anonaine, analobine, asimilobine, discretamine, stepholidine, coclaurine, orientaline, juziphine and stepharine), and a benzenoid (2-methoxybenzoic acid). These compounds support their recent reclassification from Rollinia to Annona, and that it is a typical species of the family Annonaceae. Significant antifungal and antioxidant activities were found for the methanol crude extract as well as for the lignans eudesmin, magnolin, yangambin and the alkaloid discretamine. In addition, several items of NMR data for the alkaloids were reviewed and unequivocally described in this work.

Antimicrobial photodynamic effect of extracts and oxoaporphine alkaloid isomoschatoline from Guatteria blepharophylla.

Photodynamic Therapy, a tumor therapy idealized at the beginning of the last century, emerges nowadays as a promising treatment alternative against infectious diseases. In this study we report a bioguided study of Guatteria blepharophylla phytoderivatives for antimicrobial PDT. Crude extracts and fraction from the species bark were obtained and further fractionated for substances isolation. All samples were evaluated in relation to their photophysical (absorbance and fluorescence) and photochemical properties (1,3-DPBF bleaching method). Then, bioassays were conducted using as biological models bacteria and yeast strains and a diode laser as a light source. Phytochemical analyses lead to the isolation of 5 isoquinoline alkaloids from oxoaporphine subclass, denominated GB1 to GB5. Photophysical and photochemical analysis showed that extracts, fraction and GB1 (isomoschatoline) presented absorption profile with bands at 600-700nm and were positive for singlet oxygen production. Photobiological assays indicate that these samples presented photodynamic antimicrobial activity against both gram-positive and gram-negative bacterial and some Candida ssp. yeast strains at sub-inhibitory concentrations. The susceptibility of gram-negative bacteria was significantly enhanced when CaCl2 or MgCl2 were employed. Greater energy doses and double samples dosage also decreased microbial survival. It is suggested that GB1 photodynamic activity happens through both types I and II photochemical mechanisms, but with a predominance of the latter. Phytoderivatives of G. blepharophylla promoted antimicrobial effect, however more detailed study concerning chemical composition of the crude extracts and fractions as also photophysical and photochemical characteristics of GB1 are necessary to ensure their potential as photosensitizers at antimicrobial photodynamic inactivation.

Chemical composition of the essential oil from the leaves of Anaxagorea brevipes (Annonaceae) and evaluation of its bioactivity

Abstract The essential oil obtained by hydrodistillation from leaves of Anaxagorea brevipes was analysed by gas chromatography fitted with a flame ionisation detector (GC–FID) and coupled to mass spectrometry (GC–MS). Thirty one components were identified, representing around 75.7% of total oil. The major components were β-eudesmol (13.16%), α-eudesmol (13.05%), γ-eudesmol (7.54%), guaiol (5.12%), caryophyllene oxide (4.18%) and β-bisabolene (4.10%). The essential oil showed antimicrobial activity against Gram-positive bacteria and yeast with the MIC values between 25.0 and 100 μg/mL. The highest antiproliferative activity was observed for the oil against MCF-7 (breast, TGI = 12.8 μg/mL), NCI-H460 (lung, TGI = 13.0 μg/mL) and PC-3 (prostate, TGI = 9.6 μg/mL) cell lines, while against no cancer cell line HaCat (keratinocyte) the TGI was 38.8 μg/mL. The oil exhibited a small antioxidant activity assessed through ORAC-FL assay (517 μmol TE/g). This is the first report regarding the chemical composition and bioactivity of A. brevipes essential oil.

Annona Species (Annonaceae) Oils

Abstract The genus Annona L. is one of the most important of the Annonaceae family due to its edible fruits and medicinal properties. This genus has different classes of active metabolites, such as isoquinoline and pyrimidine-β-carboline alkaloids, acetogenins, lectins, and volatile oils. The constitution of essential oils is predominantly mono and sesquiterpenes. The major constituents are α-pinene and β-pinene, myrcene, p-cymene, limonene, linalool, 1,8-cineole, caryophyllene, and caryophyllene oxide. This chapter reviews the literature on the chemical composition, bioactivity, and uses of volatile constituents from species of the genus Annona in food science. The flavor composition of the most common Annona species is summarized in this chapter, including Annona atemoya, Annona cherimolia, Annona coriacea, Annona foetida, Annona glabra, Annona muricata, Annona pickelii, Annona reticulata, Annona salzmannii, Annona senegalensis, Annona squamosa, and Annona vepretorum.

CONSTITUENTS OF ESSENTIAL OIL AND HYDROLATE OF LEAVES OF Campomanesia viatoris LANDRUM

The chemical composition of the essential oil and hydrolates of Campomanesia viatoris Landrum were investigated by gas chromatography/mass spectrometry (GC/MS) and a GC flame ionization detector (GC-FID). The major constituents were tasmanone (70.50, essential oil; 74.73%, hydrolate), flavesone (12.77, essential oil; 12.24%, hydrolate) and agglomerone (6.79, essential oil; 10.84%, hydrolate). Tasmonone was isolated and its structure was characterized by spectrometric analysis, specifically 1D and 2D nuclear magnetic resonance (NMR) and mass spectrometry (MS). These findings supports the quimiotaxonomic relationship with Campomanesia and Eucalyptus genera.

Guaianolide sesquiterpene lactones and aporphine alkaloids from the stem bark of Guatteria friesiana

Three guaianolide sesquiterpenes, denoted guatterfriesols A-C, and four aporphine alkaloid derivatives were isolated from the stem bark of the Amazonian plant Guatteria friesiana. Thus far, sesquiterpene lactones have not been described in Annonaceae. Structures of the previously undescribed compounds were established by using 1D and 2D NMR spectroscopy in combination with MS. The absolute stereochemistry was assigned via NOE NMR experiments, ECD spectroscopy, and theoretical calculations using the TDDFT approach. Among the isolated compounds, the alkaloid guatterfriesidine showed anti-glycation activity by inhibiting the formation of advanced glycation end-products (AGEs) through the prevention of oxidation in both BSA/methylglyoxal and BSA/fructose systems.

Phytochemical and Biological Properties of Lippia gracilis

Lippia gracilis Schauer is popularly known as “alecrim-da-chapada” and “candeia-de-queimar.” It is a native plant in the semiarid region of Northeast Brazil. The present chapter summarizes the phytochemical and biological properties of L. gracilis. The nonvolatile constituents of L. gracilis include flavone and flavanones, while the major volatile compounds are carvacrol, p-cymene, γ-terpinene, thymol, and thymol methyl ether. In addition, three different chemotypes such as thymol type (T), carvacrol type (C), and intermediate type, which contains both carvacrol and thymol (CT), are also found in high percentage. Its biological properties include cytotoxic, antitumor, anti-inflammatory, antinociceptive, antioxidant, antibacterial, fungicidal, leishmanicidal, amebicidal, larvicidal, molluscicidal, and acaricidal activity.