Abstract Leishmaniasis is an endemic disease caused by protozoa of the genus Leishmania, which affects around two million people worldwide. One major drawback in the treatment of leishmaniasis is the emergence of resistance to current chemotherapeutics. Medicinal and aromatic plants constitute a major source of natural organic compounds. In this study, the leaf essential oil of Cryptocarya aschersoniana was obtained by hydrodistillation in a Clevenger-type apparatus, and the chemical composition was analyzed by GC-MS and GC-FID. The essential oil of these species was predominantly constituted by monoterpene hydrocarbons (48.8%). Limonene (42.3%), linalool (9.7%) and nerolidol (8.6%) were the main constituents in the oil of C. aschersoniana. The in vitro activity of the oil was evaluated against the promastigote forms of Leishmania amazonensis, the causative agent of cutaneous leishmaniasis in humans. The essential oil of C. aschersoniana showed high activity against L. amazonensis promastigote forms (IC50 = 4.46 µg/mL), however, it also demonstrated a relatively high cytotoxicity on mouse peritoneal macrophages (CC50 = 7.71 µg/mL). This is the first report of the chemical composition and the leishmanicidal and cytotoxic activities of the leaf essential oil of C. aschersoniana.

ABSTRACT Tooth decay is a major public health problem which affects a large number of people in several countries. Even though more than 700 bacterial species have been detected in the oral cavity, Streptococcus and Lactobacillus stand out as the genera that cause tooth decay and other periodontal diseases. In this study, essential oils from Citrus aurantifolia leaves (CL-EO) and fruit peel (CP-EO) were obtained by hydrodistillation by a Clevenger-type apparatus whereas their chemical composition was analyzed by gas chromatography-flame ionization detector (GC-FID) and gas chromatography-mass spectrometry (GC-MS). Limonene (77.5 %), linalool (20.1 %), citronellal (14.5 %) and citronellol (14.2 %) were the main constituents found in the essential oils from C. aurantifolia leaves and fruit peel. Antibacterial activity of essential oils was evaluated in terms of its minimum inhibitory concentration (MIC) values by the broth microdilution method in 96-well microplates. Both CL-EO and CP-EO displayed some activity against all oral pathogens under investigation; MIC values ranged from 20 to 200 µg/mL. CL-EO and CP-EO not only had promising activity against Streptococcus mutans (MIC = 20 µg/mL) and Lactobacillus casei (31.25 µg/mL), but also displayed antibacterial activity against all studied cariogenic bacteria. Efficacy of essential oils against S. mutans and L. casei is noteworthy and should be further investigated.

ABSTRACT Abnormal multiplication of oral bacteria causes dental caries and dental plaque. These diseases continue to be major public health concerns worldwide, mainly in developing countries. In this study, the chemical composition and antimicrobial activity of the essential oil of Vitex agnus-castus leaves (VAC‒EO) collected in the North of Brazil against a representative panel of cariogenic bacteria were investigated. The antimicrobial activity of VAC-EO was evaluated in terms of its minimum inhibitory concentration (MIC) values by using the broth microdilution method in 96-well microplates. The chemical constituents of VAC-EO were identified by gas chromatography (GC‒FID) and gas chromatography‒mass spectrometry (GC‒MS). VAC‒EO displayed some activity against all the investigated oral pathogens; MIC values ranged from 15.6 to 200 μg/mL. VAC-EO had promising activity against Streptococcus mutans (MIC= 15.6 μg/mL), Lactobacillus casei (MIC= 15.6 μg/mL), and Streptococcus mitis (MIC= 31.2 μg/mL). The compounds 1,8-cineole (23.8%), (E)-β-farnesene (14.6%), (E)-caryophyllene (12.5%), sabinene (11.4%), and α-terpinyl acetate (7.7%) were the major chemical constituents of VAC‒EO. VAC-EO displays antimicrobial activity against cariogenic bacteria. The efficacy of VAC-EO against S. mutans is noteworthy and should be further investigated.

This paper reports on the chemical composition, the in vitroantischistosomal effects, and the cytotoxicity of the essential oil from the leaves of Lavandula angustifolia Mill., Lamiaceae, grown in the Southeastern Brazil. Borneol (22.4%), epi-α-muurolol (13.4%), α-bisabolol (13.1%), precocene I (13.0%), and eucalyptol (7.9%) were the major essential oil constituents. Incubation with essential oil at 200 μg/ml killed all the adult S. mansoni worms after 24 h (LC50117.7 and 103.9 μg/ml at 24 and 120 h of incubation, respectively). At a concentration of 50 μg/ ml, the essential oil significantly decreased the motor activity and reduced the percentage of egg development after 120 h. In addition, the essential oil separated all the coupled S. mansoni worm pairs into individual male and female at 25 and 50 μg/ml within 120 and 24 h, respectively. This oil was cytotoxic to GM07492-A cells at only concentrations higher than 200 µg/ml (IC50243.7 µg/ml). These data indicate that LA-EO exhibits moderate in vitro activity against adult S. mansoniand exerts remarkable effects on eggs development.