Chemical composition and antibacterial activity of essential oils from Citrus aurantifolia leaves and fruit peel against oral pathogenic bacteria.

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.

Chemical composition and evaluation of antileishmanial and cytotoxic activities of the essential oil from leaves of Cryptocarya aschersoniana Mez. (Lauraceae Juss.).

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.

Chemical composition, antioxidant and antibacterial activities of essential oils from leaves and flowers of Eugenia klotzschiana Berg (Myrtaceae).

Many essential oils (EOs) of different plant species possess interesting antimicrobial effects on buccal bacteria and antioxidant properties. Eugenia klotzschiana Berg (pêra-do-cerrado, in Portuguese) is a species of Myrtaceae with restricted distribution in the Cerrado. The essential oils were extracted through the hydrodistillation technique using a modified Clevenger apparatus (2 hours) and chemically characterized by GC-MS. The major compounds were α-copaene (10.6 %) found in oil from leaves in natura, ß-bisabolene (17.4 %) in the essential oil from dry leaves and α-(E)-bergamotene (29.9 %) in oil from flowers. The antioxidant activity of essential oils showed similarities in both methods under analysis (DPPH and ABTS˙+) and the results suggested moderate to high antioxidant activity. The antibacterial activity was evaluated by determining minimum inhibitory concentrations (MICs), using the microdilution method. MIC values below 400 µg/mL were obtained against Streptococcus salivarius (200 µg/mL), S. mutans (50 µg/mL), S. mitis (200 µg/mL) and Prevotella nigrescens (50 µg/mL). This is the first report of the chemical composition and antibacterial and antioxidant activities of the essential oils of E. klotzschiana. These results suggest that E. klotzschiana, a Brazilian plant, provide initial evidence of a new and alternative source of substances with medicinal interest.

In vitro antiparasitic activity and chemical composition of the essential oil from Protium ovatum leaves (Burceraceae).

Leishmaniasis and trypanosomiasis are globally widespread parasitic diseases which have been responsible for high mortality rates. Since drugs available for their treatment are highly hepatotoxic, nephrotoxic and cardiotoxic, adherence to therapy has been affected. Thus, the search for new, more effective and safer drugs for the treatment of these diseases is necessary. Natural products have stood out as an alternative to searching for new bioactive molecules with therapeutic potential. In this study, the chemical composition and antiparasitic activity of the essential oil from Protium ovatum leaves against trypomastigote forms of Trypanosoma cruzi and the promastigote forms of Leishmania amazonensis were evaluated. The essential oil was promising against trypomastigote forms of T. cruzi (IC50= 28.55 µg.mL-1) and L. amazonensis promastigotes (IC50 = 2.28 µg.mL-1). Eighteen chemical constituents were identified by Gas Chromatography coupled to Mass Spectrometry (GC-MS) in the essential oil, whose major constituents were spathulenol (17.6 %), caryophyllene oxide (16.4 %), ß-caryophyllene (14.0 %) and myrcene (8.4 %). In addition, the essential oil from P. ovatum leaves had moderate cytotoxicity against LLCMK2 adherent epithelial cell at the concentration range under analysis (CC50 = 150.9 µg.mL-1). It should be highlighted that this is the first report of the chemical composition and anti-Trypanosoma cruzi and anti-Leishmania amazonensis activities of the essential oil from Protium ovatum leaves.

Chemical composition of essential oils from different parts of Protium heptaphyllum (Aubl.) Marchand and their in vitro antibacterial activity.

In Brazilian folk medicine, Protium heptaphyllum is used to treat inflammatory conditions and to hasten wound repair. This paper aims to investigate the chemical composition and the in vitro antibacterial effects of the essential oils (EOs) obtained from P. heptaphyllum leaves and ripe and unripe fruits against a representative panel of oral pathogens. The GC-FID and GC-MS analysis revealed that the major components determined in P. heptaphyllum essential oils were myrcene (59.0%), ß-elemene (17.2%), limonene (12.9%), spathulenol (12.6%), α-cubebene (11.6%), germacrene D (10.6%), trans-nerolidol (9.8%), and α-cadinol (8.8%). The essential oils of the ripe and unripe fruits showed the strongest antibacterial activity against the anaerobic bacteria Prevotella nigrescens (MIC = 50 µg/mL). The leaf essential oil displayed very promising activity against Streptococcus mutans (MIC = 50 µg/mL) and Streptococcus mitis (MIC = 62.5 µg/mL). The antibacterial activity of EOs against oral pathogens is also described for the first time. [Formula: see text].

Biological properties and chemical composition of essential oil from Nectandra megapotamica (Spreng.) Mez. leaves (Lauraceae).

Nectandra megapotamica is a tree species that naturally occurs in the Atlantic Forest, Brazil. This paper aims to investigate the chemical composition and in vitro antibacterial, antileishmanial and antiproliferative activities of essential oil from N. megapotamica leaves (NM-EO). It displayed high antibacterial activity against Streptococcus mutans, S. sobrinus, Prevotella nigrescens and Bacteroides fragilis. NM-EO also exhibited high antileishmanial activity against promastigote forms of Leishmania amazonensis. Its antiproliferative activity was evaluated against the following cells: GM07429A (normal cell), MCF-7 (human breast adenocarcinoma), HeLa (human cervical adenocarcinoma) and M059J (human glioblastoma). Its major components, which were determined by GC-FID and GC-MS, were α-bisabolol (13.7%), bicyclogermacrene (10.9%), (E,E)-farnesene (10.6%), Z-caryophyllene (9.5%) and (E)-ß-farnesene (7.0%). These results suggest that N. megapotamica, a Brazilian plant, shows initial evidence of a new and alternative source of substances of medicinal interest.

Chemical composition and in vitro antibacterial and antiproliferative activities of the essential oil from the leaves of Psidium myrtoides O. Berg (Myrtaceae).

In this study, the chemical composition and antibacterial and antiproliferative potential of the essential oil obtained from fresh leaves of Psidium myrtoides (PM-EO) against oral pathogens and human tumour cell lines were investigated for the first time. GC-FID and GC-MS analyses showed that trans-ß-caryophyllene (30.9%), α-humulene (15.9%), α-copaene (7.8%), caryophyllene oxide (7.3%) and α-bisabolol (5.3%) are the major constituents of PM-EO. The antibacterial activity of PM-EO against a panel of oral pathogens was investigated in terms of their minimal inhibitory concentrations (MIC) using the broth microdilution method. PM-EO displayed moderate activity against Streptococcus mitis (MIC = 100 µg/mL), S. sanguinis (MIC = 100 µg/mL), S. sobrinus (MIC = 250 µg/mL), and S. salivarius (MIC = 250 µg/mL), and strong activity against S. mutans (MIC = 62.5 µg/mL). The antiproliferative activity in normal (GM07492A, lung fibroblasts) and tumour cell lines (MCF-7, HeLa, and M059 J) was performed using the XTT assay. PM-EO showed 50% inhibition of normal cell growth at 359.8 ± 6.3 µg/mL. Antiproliferative activity was observed against human tumour cell lines, with IC50 values significantly lower than that obtained for the normal cell line, demonstrating IC50 values for MCF-7 cells (254.5 ± 1.6 µg/mL), HeLa cells (324.2 ± 41.4 µg/mL) and M059 J cells (289.3 ± 10.9 µg/mL). Therefore, the cytotoxicity of PM-EO had little influence on the antibacterial effect, since it showed antibacterial activity at lower concentrations. Our results suggest that PM-EO is a promising source of new antibacterial and antitumour agents.

Chemical composition, antioxidant and antibacterial activities of essential oils from leaves and flowers of Eugenia klotzschiana Berg (Myrtaceae)

ABSTRACT Many essential oils (EOs) of different plant species possess interesting antimicrobial effects on buccal bacteria and antioxidant properties. Eugenia klotzschiana Berg (pêra-do-cerrado, in Portuguese) is a species of Myrtaceae with restricted distribution in the Cerrado. The essential oils were extracted through the hydrodistillation technique using a modified Clevenger apparatus (2 hours) and chemically characterized by GC-MS. The major compounds were α-copaene (10.6 %) found in oil from leaves in natura, β-bisabolene (17.4 %) in the essential oil from dry leaves and α-(E)-bergamotene (29.9 %) in oil from flowers. The antioxidant activity of essential oils showed similarities in both methods under analysis (DPPH and ABTS˙+) and the results suggested moderate to high antioxidant activity. The antibacterial activity was evaluated by determining minimum inhibitory concentrations (MICs), using the microdilution method. MIC values below 400 µg/mL were obtained against Streptococcus salivarius (200 µg/mL), S. mutans (50 µg/mL), S. mitis (200 µg/mL) and Prevotella nigrescens (50 µg/mL). This is the first report of the chemical composition and antibacterial and antioxidant activities of the essential oils of E. klotzschiana. These results suggest that E. klotzschiana, a Brazilian plant, provide initial evidence of a new and alternative source of substances with medicinal interest.

In vitro antiparasitic activity and chemical composition of the essential oil from Protium ovatum leaves (Burceraceae)

ABSTRACT Leishmaniasis and trypanosomiasis are globally widespread parasitic diseases which have been responsible for high mortality rates. Since drugs available for their treatment are highly hepatotoxic, nephrotoxic and cardiotoxic, adherence to therapy has been affected. Thus, the search for new, more effective and safer drugs for the treatment of these diseases is necessary. Natural products have stood out as an alternative to searching for new bioactive molecules with therapeutic potential. In this study, the chemical composition and antiparasitic activity of the essential oil from Protium ovatum leaves against trypomastigote forms of Trypanosoma cruzi and the promastigote forms of Leishmania amazonensis were evaluated. The essential oil was promising against trypomastigote forms of T. cruzi (IC50= 28.55 μg.mL-1) and L. amazonensis promastigotes (IC50 = 2.28 μg.mL-1). Eighteen chemical constituents were identified by Gas Chromatography coupled to Mass Spectrometry (GC-MS) in the essential oil, whose major constituents were spathulenol (17.6 %), caryophyllene oxide (16.4 %), β-caryophyllene (14.0 %) and myrcene (8.4 %). In addition, the essential oil from P. ovatum leaves had moderate cytotoxicity against LLCMK2 adherent epithelial cell at the concentration range under analysis (CC50 = 150.9 μg.mL-1). It should be highlighted that this is the first report of the chemical composition and anti-Trypanosoma cruzi and anti-Leishmania amazonensis activities of the essential oil from Protium ovatum leaves.

Cornoside and other constituents from the latex of Parahancornia amapa (Hub. ) Ducke (Apocynaceae) a medicinal plant in Northern Brazil / Cornosídeo e outros constituintes do látex de Parahancornia amapa (Hub. ) Ducke (Apocynaceae) uma planta medicinal no Norte do Brasil

Latex of Parahancornia amapa which is known as "amapa milk" in folk medicine was extracted with hexane, dichloromethane and methanol. From the hexane and dichloromethane were identified mixtures of 3-O-acyl lupeol esters such as identified previously. In the methanol extract, a large amount of carbohydrates, the phenylethanoid glucoside known as cornoside, other phenylethanoids derivatives and methylmyoinositol were identified. The analysis of IR, NMR and GC-LRMS of the natural compounds and tetra-acetylcornoside and comparison with literature data were used to identify the compounds.

O látex de Parahancornia amapa, popularmente conhecido como "leite do amapá" foi extraído com hexano, diclorometano e metanol. As frações obtidas com hexano e diclorometano forneceram misturas de 3-O-acil-lupeol e triterpenos confirmando resultados de estudos já realizados. No extrato metanólico identificou-se uma grande quantidade de mistura de carboidratos, metilmioinositol e derivados de feniletanóides tendo como principal constituinte o cornosídeo. Estes constituintes foram identificados através da análise de espectros de IV, RMN ¹H e 13C e CG-EM das frações e do derivado acetilado do cornosídeo e do metilmioinositol.

Metabólitos especiais isolados de Laseguea erecta (Apocynaceae) / Special metabolites isolated from Laseguea erecta (Apocynaceae)

Do caule de Laseguea erecta foram isolados o lupeol, a cumarina escopoletina, o lignóide pinoresinol e o glicosil-cardenoídeo, alfa-L-tevetosil-digitoxigenina. As estruturas foram identificadas com o uso de técnicas espectroscópicas de IV, RMN ¹H e 13C, incluindo técnicas especiais 1D e 2D, espectroscopia de massas e comparação com dados da literatura.

From the stem of Laseguea erecta the triterpene lupeol, the cumarine scopoletin, the lignoid pinoresinol and digitoxigenin alpha-L-tevetoside, known as thevetioside, were isolated. The structures were identified by IR, mass, ¹H and 13C NMR spectroscopy, including 1D and 2D techniques, together with comparison with literature data.