Abstract: This article describes the chemical composition of Vernonia chalybaea essential oil, and investigates its antimicrobial, antioxidant and hemolytic activities. The evaluation of the antifungal activity was performed by the broth microdilution method using strains of yeasts and dermatophytic fungi. The checkerboard technique to find antimicrobial modulatory effects was performed using ketoconazole as standard drug. The antioxidant activity was evaluated by DPPH scavenging assay and β-carotene/linoleic-acid system. The toxicity was characterized by the brine shrimp lethality test and hemolysis bioassays. The essential oil was obtained by hydrodistillation and analyzed by GC-MS method, showing to be rich in the sesquiterpenes β-caryophyllene (39.06%) and bicyclogermacrene (19.69%), and also demonstrated a relevant antifungal activity against strains of Trichophyton rubrum. In the modulatory activity assay, the essential oil of V. chalybaea and β-caryophyllene demonstrated a synergistic interaction with ketoconazole, with increasing of its antifungal action. The antioxidant activity was evidenced mainly by β-carotene/linoleic acid system, with IC50 value of 35.87 ± 0.32 µg/mL. The results suggest that V. chalybaea essential oil and β-caryophyllene are valuable natural medicinal agents with antioxidant and antimicrobial activities.
SUMMARY This work reports the chemical study, and anti-Candida spp. activity of leaf essential oil from Mangifera indica cultivars. The essential oils were obtained by hydro-distillation and analyzed by gas chromatography/mass spectroscopy. The anti-Candida spp. activity was evaluated against strains isolated from dogs by the agar-well diffusion method and the minimum inhibitory concentration (MIC) by the broth microdilution method. Tommy Atkins cultivar presented β–selinene (29.49%), caryophyllene oxide (12.40%) and humulene II epoxide (8.66%) as main constituents, while the main constituents of Rosa, Moscatel and Jasmim varieties were caryophyllene oxide (23.62, 48.42 and 30.77%, respectively) and humulene epoxide II (11.56, 23.45, and16.27%, respectively). The means of inhibition zones were 11 ± 0.71, 13.5 ± 3.54, 10.5 ± 0.71 and 13.5 ± 0.71mm to Tommy Atkins, Rosa, Moscatel and Jasmim varieties, respectively. For Tommy Atkins, the MIC ranged from 0.62 to 1.25 mg/mL; for Rosa, ranged from 0.31 to 1.25 mg/mL; for Jasmim ranged from 0.31 to 0.62 mg/mL; while for the Moscatel variety the MIC value was 1.25 mg/mL for all Candida strains. Essential oils of four M. indica cultivars were active in vitro against Candida spp., demonstrating good antifungal activity and can be a useful source of antifungal compounds for veterinary medicine.
RESUMO Este trabalho descreve a composição química e a atividade anti-Candida spp. de óleos essenciais de folhas de diversos cultivares de Mangifera indica. Os óleos essenciais foram obtidos por meio de hidrodestilação e analisados por cromatografia de gás acoplada à espectrometria de massa. A atividade anti-Candida spp. foi avaliada contra cepas isoladas de cães pelo método de difusão em ágar e a concentração inibitória mínima (CIM) pelo método de microdiluição em caldo. O cultivar Tommy Atkins apresentou β-selineno (29.49%), óxido de cariofileno (12.40%) e humuleno II epoxido (8.66%) como seus constituintes principais, enquanto que os principais componentes das variedades Rosa, Moscatel e Jasmim foram óxido de cariofileno (23,62, 48,42 e 30,77%, respectivamente) e humuleno II epoxido (11,56, 23,45 e 16,27%, respectivamente). As médias de zona de inibição foram 11 ± 0,71, 13,5 ± 3,54, 10,5 ± 0,71 e 13,5 ± 0,71mm respectivamente para os cultivares Tommy Atkins, Rosa, Moscatel e Jasmim. Para a variedade Tommy Atkins, a CIM variou de 0,62 a 1,25 mg/mL; para Rosa, 0.31 a 1.25 mg/mL; para Jasmim os valores variaram de 0,31 a 0,62 mg/mL; ao passo que para a variedade Moscatel o valor de CIM foi 1,25 mg/mL para todas as cepas de Candida spp. Os óleos essenciais das quatro variedades de M. indica foram ativos in vitro contra Candida spp., demonstrando boa atividade antifúngica, podendo ser uma fonte útil de compostos antifúngicos para uso na medicina veterinária.