Fungal pathologies caused by the genus Candida have increased in recent years due to the involvement of immunosuppressed people and the advance of resistance mechanisms acquired by these microorganisms. Liposomes are nanovesicles with lipid bilayers in which they store compounds. α-Bisabolol is a sesquiterpene with proven biological activities, and in this work it was tested alone in liposomes and in association with Fluconazole in vitro to evaluate the antifungal potential, Fluconazole optimization, and virulence inhibitory effect in vitro. Antifungal assays were performed against standard strains of Candida albicans, Candida tropicalis, and Candida krusei by microdilution to identify the IC₅₀ values and to obtain the cell viability. The Minimum Fungicidal Concentration (MFC) was performed by subculturing on the solid medium, and at their subinhibitory concentration (Matrix Concentration (MC): 16,384 µg/mL) (MC/16), the compounds, both isolated and liposomal, were associated with fluconazole in order to verify the inhibitory effect of this junction. Tests to ascertain changes in morphology were performed in microculture chambers according to MC concentrations. Liposomes were characterized from the vesicle size, polydispersity index, average Zeta potential, and scanning electron microscopy. The IC₅₀ value of the liposomal bisabolol associated with fluconazole (FCZ) was 2.5 µg/mL against all strains tested, revealing a potentiating effect. Liposomal bisabolol was able to potentiate the effect of fluconazole against the CA and CT strains by reducing its concentration and completely inhibiting fungal growth. α-Bisabolol in liposomal form inhibited the morphological transition in all strains tested at a concentration of MC/8. The liposomes were homogeneous, with vesicles with diameters of 203.8 nm for the liposomal bisabolol and a surface charge potential of −34.2 mV, conferring stability to the nanosystem. Through scanning microscopy, the spherical shapes of the vesicles were observed.

Ocotea duckei Vattimo, popularly known as “louro-de-cheiro”, “louro-pimenta”, and “louro-canela” is a member of the Lauraceae family found in the Northeast region of Brazil. It is popularly used to treat neuralgia, dyspepsia, anorexia and pain. This current study aimed to promote the isolation and the identification / determination of new secondary metabolites of the species O. duckei Vattimo. In order to obtain the vegetable drug of O. duckei, its stem barks were harvested and submitted to a drying process followed by pulverization. The Crude Ethanolic Extract (BSE), obtained from the vegetable drug, was then subjected to an alkaloid extraction protocol in order to generate its Total Alkaloid Fraction (TAF). The isolation and identification of chemical compounds were carried out by chromatographic and spectroscopic methods respectively. The chemical investigation of O. duckei resulted in the isolation of three compounds: Ocoteaduccin A (OD-1, 0.020 g), Ocoteaduccin B (OD-2, 0.015 g), and N-methylcoclaurine (OD-3, 0.008 g). O. duckei proved to be a promising species, due to the variety of isolated chemical compounds. Further chemical, pharmacological and toxicological studies must be conducted in order to improve the phytochemical knowledge about this plant.

As plantas têm sido utilizadas mundialmente como fonte de moléculas bioativas com potencial de tratar diversas doenças, porém muitas dessas espécies não foram suficientemente estudadas. Essas plantas podem conter substâncias tóxicas capazes de causar danos à saúde da população. Nesse contexto, objetivou-se determinar a concentração letal 50% (CL50) de extratos de Erythroxylum caatingae e Erythroxylum revolutum, como parâmetro de toxicidade/bioatividade. Foram testados o extrato metanólico e a fase aquosa básica de E. caatingae e o extrato metanólico de E. revolutum. Foi adotado o bioensaio com Artemia salina, sendo cada concentração dos extratos testada em triplicata e repetida em pelo menos três experimentos. As CL50 foram analisadas por regressão não-linear. Os valores de CL50 para os extratos metanólico e da fase aquosa de E. caatingae e para o extrato bruto de E. revolutum foram de 203,7 (190,1-218,2) µg/mL, 1.074,0 (949,6-1.214,0) µg/mL e 308,1 (241,1-393,6) µg/mL, respectivamente. Dessa forma, conclui-se que existe uma concentração tóxica dos extratos testados, bem como, uma relação diretamente proporcional entre a concentração do extrato e a mortalidade para A. salina. O extrato metanólico de E. caatingae apresentou-se mais tóxico, enquanto a fase aquosa teve a menor letalidade.

Ocotea duckei, known as Louro-de-cheiro, belongs to the Lauraceae family and presents lignoid yangambine (YAN) as the main plant marker. This work aimed to develop and validate an analytical method by high performance liquid chromatography for the quantification of YAN. The sample used was the crude ethanolic extract (CEE) obtained from aerial parts. In the developed method, a C18 column was used. The mobile phase was composed of acetonitrile and water (45:55), whereas the method parameters included mobile phase flow rate at 0.8 mL/min, oven temperature at 40°C, and monitoring at 205 nm. In the validation, the parameters of selectivity, linearity, precision, accuracy, robustness, limits of detection and quantification were evaluated. As a result, the developed method is in accordance with the guidelines for validation of analytical methods and presented satisfactory chromatographic parameters for YAN determination. Thus, the present analytical methodology can be applied in the quality control of O. duckei raw materials.