Eugenol-Rich Essential Oil from Pimenta dioica: In Vitro and In Vivo Potentialities against Leishmania amazonensis.

Pimenta dioica L. is one the most recognized species with diverse biological activities. In this study, in vitro activity and in vivo efficacy of essential oil from P. dioica (EO-Pd) was evaluated. The main compound was also included in the animal studies and its in silico prediction related to biological activities, molecular ligands, drug likeness, and ADME (absorption, distribution, metabolism, and excretion) properties are listed. The chemical composition analyzed by GC-MS retrieved 45 components, which the most abundant compound was the eugenol (80.1%). The EO-Pd was able to inhibit the growth of L. amazonensis (IC50 = 9.7 ± 0.7 and 11.3 ± 2.1 µg/mL, promastigotes and amastigotes, respectively). The cytotoxicity assay showed a CC50 of 104.5 ± 0.9 µg/mL and a selectivity index of 9. In the model of cutaneous leishmaniasis in BALB/c mice, the effect of EO-Pd and eugenol was observed after treatment at 30 mg/kg by intralesional route with 5 administrations every 4 days. In the in silico predictions, some targets that justified the antileishmanial activity of eugenol and good drug like properties for this compound, were obtained. This study showed for first time the potential of EO-Pd to inhibit L. amazonensis, which could be linked to the activity of major compound eugenol.

Actividad insecticida de aceites esenciales sobre Blatella germanica (Linneaus, 1767) (Dictyoptera: Blattellidae) / nsecticidal activity of essential oils against Blatella germanica (Linneaus, 1767) (Dictyoptera: Blattellidae)

Blattella germanica (Linneaus, 1767) es una especie de cucaracha considerada plaga de la salud pública por estar asociada a gran número de microorganismos causantes de enfermedades al hombre. Para su control se utilizan diferentes tipos de formulaciones a base de insecticidas sintéticos a los cuales en su gran mayoría es resistente. En este contexto existe un interés creciente por los insecticidas botánicos. En el siguiente trabajo se evaluaron los aceites de Citrus aurantium (L.,1753), Ocimum basilicum (L.,1753), Piper aduncum subsp ossanum (C.DC. Saralegui) y Eucalyptus globulus (Labill, 1800) mediante aplicación tópica de un microlitro en el primer esternito abdominal de los individuos. Los cuatro aceites mostraron actividad insecticida sobre adultos de B. germanica con CL50 que oscilaron entre 58 µg/µL para O. basilicum y 250 µg/µL para P. aduncum(AU)´

Blattella germanica (Linneaus, 1767) is a cockroach species considered a public health pest, since it is associated with a great number of disease-causing microorganisms in humans. For its control, different types of synthetic-based insecticidal formulations are used, to which it is mostly resistant. In this context, there is a growing interest in botanical insecticides. In this research, oils from Citrus aurantium (L., 1753), Ocimum basilicum (L., 1753), Piper aduncum subsp. ossanum (C.DC. Saralegui), and Eucalyptus globulus (Labill, 1800) were evaluated by topical application of 1 µL to the first abdominal sternum of the individuals. The four essential oils evaluated showed insecticidal activity against adult B. germanica with LC50 ranging from 58µg/µL for O. basilicum to 250µg/µL for P. aduncum(AU)´

Molecular barcode and morphological analysis of Smilax purhampuy Ruiz, Ecuador.

Smilax plants are distributed in tropical, subtropical, and temperate regions in both hemispheres of the world. They are used extensively in traditional medicines in a number of countries. However, morphological and molecular barcodes analysis, which may assist in the taxonomic identification of species, are lacking in Ecuador. In order to evaluate the micromorphological characteristics of these plants, cross sections of Smilax purhampuy leaves were obtained manually. The rhizome powder, which is typically used in traditional medicines, was analyzed for micromorphological characteristics. All samples were clarified with 1% sodium hypochlorite. Tissues were colored with 1% safranin in water and were fixed with glycerinated gelatin. DNA was extracted from the leaves using a modified CTAB method for molecular barcode characterization and PCR was performed using primers to amplify the different loci including the plastid genome regions atpF-atpH spacer, matK gene, rbcL gene, rpoB gene, rpoC1 gene, psbK-psbI spacer, and trnH-psbA spacer; and the nuclear DNA sequence ITS2. A DNA sequence similarity search was performed using BLAST in the GenBank nr database and phylogenetic analysis was performed using the maximum likelihood method according to the best model identified by MEGAX using a bootstrap test with 1,000 replicates. Results showed that the micromorphological evaluation of a leaf cross section depicted a concave arrangement of the central vein, which was more pronounced in the lower section and had a slight protuberance. The micromorphological analysis of the rhizome powder allowed the visualization of a group of cells with variable sizes in the parenchyma and revealed thickened xylematic vessels associated with other elements of the vascular system. Specific amplicons were detected in DNA barcoding for all the barcodes tested except for the trnH-psbA spacer. BLAST analysis revealed that the Smilax species was predominant in all the samples for each barcode; therefore, the genus Smilax was confirmed through DNA barcode analysis. The barcode sequences psbK-psbI, atpF-atpH, and ITS2 had a better resolution at the species level in phylogenetic analysis than the other barcodes we tested.

Essential Oil from Melaleuca leucadendra: Antimicrobial, Antikinetoplastid, Antiproliferative and Cytotoxic Assessment.

Essential oils (EOs) are known for their use in cosmetics, food industries, and traditional medicine. This study presents the chemical composition and therapeutic properties against kinetoplastid and eukaryotic cells of the EO from Melaleucaleucadendra (L.) L. (Myrtaceae). Forty-five compounds were identified in the oil by GC-MS, containing a major component the 1,8-cineole (61%). The EO inhibits the growth of Leishmania amazonensis and Trypanosoma brucei at IC50 values <10 µg/mL. However, 1,8 cineole was not the main compound responsible for the activity. Against malignant (22Rv1, MCF-7, EFO-21, including resistant sublines MCF-7/Rap and MCF-7/4OHTAMO) and non-malignant (MCF-10A, J774A.1 and peritoneal macrophage) cells, IC50 values from 55 to 98 µg/mL and from 94 to 144 µg/mL were obtained, respectively. However, no activity was observed on Staphylococcus aureus, Enterococcus faecalis, Escherichia coli, Pseudomonas aeruginosa, Aspergillus niger, Candida parapsilosis, Microsporum canis, or Trypanosoma cruzi. The EO was able to control the lesion size and parasite burden in the model of cutaneous leishmaniasis in BALB/c mice caused by L. amazonensis compared to untreated animals (p < 0.05) and similar with those treated with Glucantime® (p > 0.05). This work constitutes the first evidence of antiproliferative potentialities of EO from M. leucadendra growing in Cuba and could promote further preclinical investigations to confirm the medical value of this plant, in particular for leishmaniasis treatment.

Bixa orellana L. (Bixaceae) and Dysphania ambrosioides (L.) Mosyakin & Clemants (Amaranthaceae) Essential Oils Formulated in Nanocochleates against Leishmania amazonensis.

Leishmaniasis is a group of neglected tropical diseases caused by protozoan parasites of the Leishmania genus. The absence of effective vaccines and the limitations of current treatments make the search for effective therapies a real need. Different plant-derived essential oils (EOs) have shown antileishmanial effects, in particular from Bixa orellana L. (EO-Bo) and Dysphania ambrosioides (L.) Mosyakin & Clemants (EO-Da). In the present study, the EO-Bo and EO-Da, formulated in nanocochleates (EO-Bo-NC and EO-Da-NC, respectively), were evaluated in vitro and in vivo against L. amazonensis. The EO-Bo-NC and EO-Da-NC did not increase the in vitro inhibitory activity of the EOs, although the EO-Bo-NC showed reduced cytotoxic effects. In the animal model, both formulations (30 mg/kg/intralesional route/every 4 days/4 times) showed no deaths or weight loss greater than 10%. In the animal (mouse) model, EO-Bo-NC contributed to the control of infection (p < 0.05) in comparison with EO-Bo treatment, while the mice treated with EO-Da-NC exhibited larger lesions (p < 0.05) compared to those treated with EO-Da. The enhanced in vivo activity observed for EO-Bo-NC suggests that lipid-based nanoformulations like nanocochleates should be explored for their potential in the proper delivery of drugs, and in particular, the delivery of hydrophobic materials for effective cutaneous leishmaniasis treatment.

Morphological and molecular barcode analysis of the medicinal tree Mimusops coriacea (A.DC.) Miq. collected in Ecuador.

BACKGROUND: Mimusops coriacea (A.DC.) Miq., (Sapotaceae), originated from Africa, were introduced to coastal areas in Ecuador where it is not extensively used as a traditional medicine to treat various human diseases. Different therapeutically uses of the species include: analgesic, antimicrobial, hypoglycemic, inflammation and pain relieve associated with bone and articulation-related diseases. Furthermore, Mimusops coriacea could be used as anti-oxidant agent. However, botanical, chemical or molecular barcode information related to this much used species is not available from Ecuador. In this study, morphological characterization was performed from leaves, stem and seeds. Furthermore, genetic characterization was performed using molecular barcodes for rbcL, matk, ITS1 and ITS2 using DNA extracted from leaves. METHODS: Macro-morphological description was performed on fresh leaves, stem and seeds. For anatomical evaluation, tissues were embedded in paraffin and transversal dissections were done following incubation with sodium hypochlorite and safranin for coloration and fixated later in glycerinated gelatin. DNA extraction was performed using a modified CTAB protocol from leaf tissues, while amplification by PCR was accomplished for the molecular barcodes rbcL, matK, ITS1 and ITS2. Sequence analysis was performed using blast in the GenBank. Phylogenetic analysis was performed with accessions queried in the GenBank belonging to the subfamily Sapotoideae. RESULTS: Leaf size was 13.56 ± 1.46 × 7.49 ± 0.65 cm; where is a macro-morphological description of the stem (see Methods). The peel of the seeds is dark brown. Sequence analysis revealed that amplicons were generated using the four barcodes selected. Phylogenetic analysis indicated that the barcodes rbcL and matK, were not discriminated between species within the same genus of the subfamily Sapotoideae. On the other hand, the ITS1 and ITS2 were discriminative at the level of genus and species of the Sapotoideae.

Chemical Composition, Antimicrobial and Antiparasitic Screening of the Essential Oil from Phania matricarioides (Spreng.) Griseb.

Essential oils (EOs) have gained increasing attention due to their pharmacological effectiveness, and they also constitute some of the most popular natural products. In this study, we present the chemical characterization of the EO from Phania matricarioides and the in vitro activity/selectivity against a wide panel of bacteria, fungi and parasitic protozoa. Forty-five compounds were identified in the studied EO, of which lavandulyl acetate (40.1%) and thymyl isobutyrate (13.9%) were the major components. The EO did not inhibit bacterial or fungal growth at the maximum concentration tested (64 µg/mL), although it displayed activity on all evaluated protozoa (IC50 values ranging from 2.2 to 56.6 µg/mL). In parallel, the EO demonstrated a noteworthy cytotoxic activity against peritoneal macrophages (CC50 values of 28.0 µg/mL). The most sensitive microorganism was Trypanosoma cruzi, which had a superior activity (IC50 = 2.2 µg/mL) and selectivity (SI = 13) in respect to other parasitic protozoa and the reference drug (p < 0.05). Further in vivo studies are needed to evaluate the potential use of this EO and the main compounds as antitrypanosomal agents. To our knowledge, this is the first report of chemical characterization and antimicrobial assessment of the EO from P. matricarioides.

Comparative Pharmacognosy, Chemical Profile and Antioxidant Activity of Extracts from Phania matricarioides (Spreng.) Griseb. Collected from Different Localities in Cuba.

Phania matricarioides (Spreng.) Griseb. is a traditionally used plant with various pharmacological properties. However, there are only scarce reports about the phytochemistry and biological activity of this plant. In this work, P. matricarioides was collected from three different localities of Cuba: PmB (collected in Bauta, Artemisa), PmC (collected in Cangrejeras, Artemisa), and PmI (collected in La Lisa, Havana), extracted with aqueous ethanol, and analyzed macroscopically and microscopically. The extracts were screened for phytochemical contents, analyzed by TLC and HPLC, and screened for antioxidant activity using the FRAP and DPPH assays. Macroscopic analysis showed similar results for all samples; however, microscopic, physicochemical and phytochemical studies showed appreciable differences. In particular, the total solid of PmC extract was higher (1.94 ± 0.03%) than the other samples. In HPLC profiles, quercetin was identified in the three samples and a greater similarity between samples PmB and PmI was observed. All samples demonstrated radical-scavenging antioxidant activity by the DPPH assay, which PmC also demonstrated the smaller (p < 0.05) value (IC50 = 27.4 ± 0.1 µg/mL), but was statistically superior (p < 0.05) to vitamin C (IC50 = 23.7 ± 0 µg/mL). Also, in the FRAP assay, a higher vitamin C equivalent of PmC was significantly superior (p < 0.05) to the other extracts at the evaluated concentrations, which is likely due to a higher concentration of quercetin. In conclusion, P. matricarioides could constitute a potential resource in the field of phytotherapeutic products, and the results obtained can contribute to the development of the quality control norms for this species.

Interaction of ascaridole, carvacrol, and caryophyllene oxide from essential oil of Chenopodium ambrosioides L. with mitochondria in Leishmania and other eukaryotes.

The antileishmanial activity of the essential oil (EO) from Chenopodium ambrosioides L. has been demonstrated in vitro and in animal models, attributed to the major components of the EO. This study focused on the effects of the three major EO compounds carvacrol, caryophyllene oxide (Caryo), and the antileishmanial endoperoxide ascaridole (Asc) on mitochondrial functions in Leishmania tarentolae promastigotes (LtP). EO and Caryo were able to partially inhibit the leishmanial electron transport chain, whereas other components failed to demonstrate a direct immediate effect. Caryo demonstrated inhibition of complex III activity in LtP and in isolated complex III from other species. The formation of superoxide radicals was studied in Leishmania by electron spin resonance spectroscopy in the presence of iron chelators wherein selected compounds failed to trigger a significant immediate additional superoxide production in LtP. However, upon prolonged incubation of Leishmania with Asc and especially in the absence of iron chelators (allowing the activation of Asc), an increased superoxide radical production and significant impairment of mitochondrial coupling in Leishmania was observed. Prolonged incubation with all EO components resulted in thiol depletion. Taken together, the major components of EO mediate their leishmanicidal activity via different mitochondrial targets and time profiles. Further studies are required to elucidate possible synergistic effects of carvacrol and Asc and the influence of minor compounds.

In Vitro and In Vivo Evaluation of Essential Oil from Artemisia absinthium L. Formulated in Nanocochleates against Cutaneous Leishmaniasis.

Background: Leishmaniasis is a zoonotic disease caused by protozoan parasites from Leishmania genus. Currently, there are no effective vaccines available and the available therapies are far from ideal. In particular, the development of new therapeutic strategies to reduce the infection caused by Leishmania amazonensis could be considered desirable. Different plant-derived products have demonstrated antileishmanial activity, including the essential oil (EO) from Artemisia absinthium L. (EO-Aa), Asteraceae. Methods: In the present study, the EO-Aa formulated in nanocochleates (EO-Aa-NC) was investigated in vitro against intracellular amastigotes of L. amazonensis and non-infected macrophages from BALB/c mice. In addition, the EO-Aa-NC was also evaluated in vivo against on experimental cutaneous leishmaniasis, which body weight, lesion progression, and parasite load were determined. Results: EO-Aa-NC displayed IC50 values of 21.5 ± 2.5 µg/mL and 27.7 ± 5.6 µg/mL against intracellular amastigotes of L. amazonensis and non-infected peritoneal macrophage, respectively. In the animal model, the EO-Aa-NC (30 mg/kg/intralesional route/every 4 days 4 times) showed no deaths or weight loss greater than 10%. In parallel, the EO-Aa-NC suppressed the infection in the murine model by approximately 50%, which was statistically superior (p < 0.05) than controls and mice treated with EO-Aa. In comparison with Glucantime®, EO-Aa-NC inhibited the progression of infection as efficiently (p > 0.05) as administration of the reference drug. Conclusions: Encochleation of EO-Aa resulted in a stable, tolerable, and efficacious antileishmanial formulation, facilitating systemic delivery of EO, with increased activity compared to administration of the free EO-Aa. This new formulation shows promising potential to future studies aimed at a new therapeutic strategy to treat leishmaniasis.

Essential Oil from Piper aduncum: Chemical Analysis, Antimicrobial Assessment, and Literature Review.

Background: The challenge in antimicrobial chemotherapy is to find safe and selective agents with potency that will not be compromised by previously developed resistance. Terrestrial plants could provide new leads to antibacterial, antifungal, or antiprotozoal activity. Methods: The essential oil (EO) of Piper aduncum L. (Piperaceae) from Cuba was analyzed by gas chromatography-mass spectrometry (GC-MS). A cluster analysis of P. aduncum EO compositions reported in the literature was carried out. The EO was screened against a panel of microorganisms (bacteria, fungi, parasitic protozoa) as well as for cytotoxicity against human cells. In addition, a review of scientific literature and a bibliometric study was also conducted. Results: A total of 90 compounds were identified in the EO, of which camphor (17.1%), viridiflorol (14.5%), and piperitone (23.7%) were the main components. The cluster analysis revealed at least nine different chemotypes. The EO did not show notable activity against bacteria or fungi, but was active against parasitic protozoa. Conclusions: The results from this study indicate P. aduncum from Cuba is a unique chemotype, support the importance of P. aduncum EOs as medicines, and demonstrate the promise of Cuban P. aduncum EO as a chemotherapeutic agent against parasitic protozoal infections.

Chemical Characterization, Antileishmanial Activity, and Cytotoxicity Effects of the Essential Oil from Leaves of Pluchea carolinensis (Jacq.) G. Don. (Asteraceae).

Current strategies to control leishmaniasis are mainly based on chemotherapy. However, none of the available drugs can be considered to be ideal to treat this disease. Because of the hydrophobic nature and bioactivities of their components, essential oils (EOs) can be considered as important sources for developing agents against intracellular pathogens, such as Leishmania parasites. In this study, we report the chemical characterization, antileishmanial activities, and cytotoxicity effect of the EO from Pluchea carolinensis (Jacq.) G. Don. (Asteraceae). Chemical analysis revealed that EO from aerial part from P. carolinensis is composed of 44 compounds. The main component was selin-11-en-4α-ol, which made up 51.0%. In vitro antileishmanial studies showed that P. carolinensis EO inhibited the growth of promastigotes (IC50  = 24.7 ± 7.1 µg/mL) and amastigotes (IC50  = 6.2 ± 0.1 µg/mL) of Leishmania amazonensis, while cytotoxicity evaluation revealed fivefold higher values than those for the parasites. In a model of experimental cutaneous leishmaniasis in BALB/c mice, five doses of EO at 30 mg/kg by intralesional route demonstrated smaller lesion size and parasite burden (p < 0.05) compared with animals treated with Glucantime® and untreated mice. In conclusion, in vitro and in vivo results showed the potentialities of EO from P. carolinensis with the future possibility of a new alternative in the treatment for leishmaniasis. Copyright © 2017 John Wiley & Sons, Ltd.

Chemodiversity Associated with Cytotoxicity and Antimicrobial Activity of Piper aduncum var. ossanum.

Chemical analysis, antimicrobial activity and cytotoxic effects of essential oils (EOs) from leaves of Piper aduncum var. ossanum from two localities Bauta (EO-B) and Ceiba (EO-C), Artemisa Province, Cuba, were determined. EOs were obtained by hydrodistillation and analyzed by gas chromatography/mass spectrometry. EO-B demonstrated higher activity against S. aureus and L. amazonensis; while a lower cytotoxicity on mammalian cells was observed. Both EOs displayed the same activity against Plasmodium falciparum, Trypanosoma cruzi, Trypanosoma brucei, and Leishmania infantum. Both EOs were inactive against Escherichia coli and Candida albicans.

Combinations of ascaridole, carvacrol, and caryophyllene oxide against Leishmania.

To date there are no vaccines against Leishmania and chemotherapy remains the mainstay for the control of leishmaniasis. The drugs currently used for leishmaniasis therapy are significantly toxic, expensive, and result in a growing frequency of refractory infections. In this study, we evaluated the effect of combinations of the main components of essential oil from Chenopodium ambrosioides (ascaridole, carvacrol, and caryophyllene oxide) against Leishmaniaamazonensis. Anti-leishmanial effects of combinations of pure compounds were evaluated in vitro and the fractional inhibitory concentration (FIC) indices were calculated. BALB/c mice infected with L. amazonensis were treated with different concentrations of ascaridole-carvacrol combinations by intralesional doses every 4 days. Disease progression and parasite burden in infected tissues were determined. In vitro experiments showed a synergistic effect of the combination of ascaridole-carvacrol against promastigotes of Leishmania with a FIC index of 0.171, while indifferent activities were observed for ascaridole-caryophyllene oxide (FIC index=3.613) and carvacrol-caryophyllene oxide (FIC index=2.356) combinations. The fixed ratio method showed that a 1:4 ascaridole-carvacrol ratio produced a better anti-protozoal activity on promastigotes, lower cytotoxicity, and synergistic activity on intracellular amastigotes (FIC index=0.416). Significant differences (p<0.05) in lesion size and parasite burden were demonstrated in BALB/c mice experimentally infected and treated with the ascaridole-carvacrol combinations compared with control animals. Carvacrol showed significant higher anti-radical activity in the DPPH assay compared with caryophyllene oxide. Electron spin resonance spectroscopy in combination with spin trapping suggested the presence of carbon-centered radicals after activation of ascaridole by Fe(2+). The intensity of the signals is preferably decreased upon addition of carvacrol. The ascaridole-carvacrol combination could represent a future alternative to monotherapeutic anti-leishmanial agents.

Essential oil from Chenopodium ambrosioides and main components: activity against Leishmania, their mitochondria and other microorganisms.

Chenopodium ambrosioides is an aromatic herb used by native people to treat parasitic diseases. The aim of this work is to compare the in vitro anti-leishmanial activity of the essential oil (EO) from C. ambrosioides and its major components (ascaridole, carvacrol and caryophyllene oxide) and study their mechanism of action and activity against a panel of microorganism. Antileishmanial activity and cytotoxicity of the EO and major components was study. In addition, experiments to elucidate the mechanism of action were perform and activities against other microorganisms (bacteria, fungi and protozoa) were evaluate. All products were active against promastigote and amastigote forms of Leishmania. Ascaridole exhibited the better antileishmanial activity and the EO the highest selectivity index. The exploration of the mechanism suggests that the products cause a breakdown of mitochondrial membrane potential and a modification of redox indexes. Only EO showed antiprotozoal effect against Plasmodium falciparum and Trypanosoma brucei; while no activity against bacteria and fungi was observed. Our results demonstrate the potentialities of EO in cellular and molecular system, which could be consider in future studies to develop new antileishmanial drugs with a wide anti-parasitic spectrum.

Antileishmanial activity of the essential oil from Bixa orellana.

Leishmaniasis is a neglected tropical disease caused by Leishmania protozoa. There is currently no vaccine against leishmaniasis, and chemotherapy remains the only effective control. However, conventional drugs are toxic, expensive, and require long periods of treatment, and resistance to clinical chemotherapeutic agents is emerging. Recent research on plants has shown a successful approach to obtain new antileishmanial alternatives. Herein, the in vitro and in vivo effects of the essential oil from Bixa orellana seeds against Leishmania amazonensis were evaluated. A total of 73 compounds were detected by gas chromatography-mass spectrometry analysis, of which ishwarane (18.6%) and geranylgeraniol (9.1%) were the major components. The oil showed activity against intracellular amastigote form (IC50 = 8.5 µg/mL), while the cytotoxic concentration was sevenfold higher for the host cells. The ability of Bixa oil to control disease progression of established cutaneous leishmaniasis in BALB/c mice was demonstrated, after a treatment with 30 mg/kg by intraperitoneal administration over 14 days. The present study reports for the first time the antileishmanial potentialities of the essential oil from B. orellana.

Activity of Cuban Plants Extracts against Leishmania amazonensis.

Natural products have long been providing important drug leads for infectious diseases. Leishmaniasis is a major health problem worldwide that affects millions of people especially in the developing nations. There is no immunoprophylaxis (vaccination) available for Leishmania infections, and conventional treatments are unsatisfactory; therefore, antileishmanial drugs are urgently needed. In this work, 48 alcoholic extracts from 46 Cuban plants were evaluated by an in vitro bioassay against Leishmania amazonensis. Furthermore, their toxicity was assayed against murine macrophage. The three most potent extracts against the amastigote stage of Leishmania amazonensis were from Hura crepitans, Bambusa vulgaris, and Simarouba glauca.

Chemical composition and anti-proliferative properties of Bursera graveolens essential oil.

Bursera graveolens is a wild tree of commercial importance native to the Neotropics, which has been widely used in folk medicine. In the present study, the chemical composition and anti-proliferative properties of the essential oil from B. graveolens were assayed. The chemical composition of the essential oil, determined by GC-MS, was complex and dominated by limonene (26.5%). Bursera oil inhibited the growth of MCF-7 breast tumor cells as well as amastigotes of L. amazonensis, with IC50 values of 48.9 +/- 4.3 and 36.7 +/- 4.7 microg/mL, respectively. In addition, the cytotoxicity of the oil was 103.9 +/- 7.2 microg/mL against peritoneal macrophages from BALB/c mice. These results demonstrate that the essential oil from B. graveolens is a promissory antiproliferative product.

Effect of Bixa orellana against Leishmania amazonensis.

BACKGROUND: In the present study, an activity of Bixa orellana extract against Leishmania amazonensis was demonstrated. RESULT: Experimentally infected BALB/c mice were treated with B. orellana extract which showed a significant activity against promastigote and amastigote forms of L. amazonensis. CONCLUSION: This study supports the importance of natural sources as antileishmanial drugs.

Antileishmanial assessment of leaf extracts from Pluchea carolinensis, Pluchea odorata and Pluchea rosea.

OBJECTIVE: To evaluate the antileishmanial activity of different extracts from three Cuban Pluchea species. METHODS: In in vitro assays the IC(50) was calculated in the promastigotes and amastigotes forms as cytotoxicity in murine macrophages. In leishmaniasis cutanea experiment, mortality, weight loss, lesion size and burden parasite were measured. RESULTS: Extracts evaluated showed inhibitive effect on growing of promastigote form; however, active extracts caused a high toxicity. Ethanol and n-hexane extracts demonstrated specific antileishmanial activity. Ethanol and n-hexane extracts from Pluchea carolinensis (P. carolinensis) caused similar inhibition against amastigote form. The intraperitoneal administration of the ethanol extract of P. carolinensis at 100 mg/kg prevented lesion development compared with control groups. CONCLUSIONS: The antileishmanial experiment suggests that ethanol extracts from P. carolinensis is the most promising. Further studies are still needed to evaluate the potential of this plant as a source of new antileishmanial agents.