Molecular modeling study of natural products as potential bioactive compounds against SARS-CoV-2.

CONTEXT: The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the causative agent of the COVID-19 infection and responsible for millions of victims worldwide, remains a significant threat to public health. Even after the development of vaccines, research interest in the emergence of new variants is still prominent. Currently, the focus is on the search for effective and safe drugs, given the limitations and side effects observed for the synthetic drugs administered so far. In this sense, bioactive natural products that are widely used in the pharmaceutical industry due to their effectiveness and low toxicity have emerged as potential options in the search for safe drugs against COVID-19. Following this line, we screened 10 bioactive compounds derived from cholesterol for molecules capable of interacting with the receptor-binding domain (RBD) of the spike protein from SARS-CoV-2 (SC2Spike), responsible for the virus's invasion of human cells. Rounds of docking followed by molecular dynamics simulations and binding energy calculations enabled the selection of three compounds worth being experimentally evaluated against SARS-CoV-2. METHODS: The 3D structures of the cholesterol derivatives were prepared and optimized using the Spartan 08 software with the semi-empirical method PM3. They were then exported to the Molegro Virtual Docking (MVD®) software, where they were docked onto the RBD of a 3D structure of the SC2Spike protein that was imported from the Protein Data Bank (PDB). The best poses obtained from MVD® were subjected to rounds of molecular dynamics simulations using the GROMACS software, with the OPLS/AA force field. Frames from the MD simulation trajectories were used to calculate the ligand's free binding energies using the molecular mechanics - Poisson-Boltzmann surface area (MM-PBSA) method. All results were analyzed using the xmgrace and Visual Molecular Dynamics (VMD) software.

Toxicological Effects of Copaiba Oil (Copaifera spp.) and Its Active Components.

Vegetable oils are among the most important traditional resources of Amazonia. Oleoresins are a type of oil that have interesting characteristics and highly bioactive properties with pharmacological potential. Oleoresins produced in the trunks of Copaifera (Fabaceae) spp. trees, known as copaiba oils, are made up of terpenes from the sesquiterpene (volatile) and diterpene (resinous) classes, but in amounts that vary between species and depending on several factors, such as soil type. Despite being used for medicinal purposes, via topical and oral application, the toxic effects of copaiba oils and their constituents are little known. The current paper reviews the toxicological studies, both in vitro and in vivo, described in the literature for copaiba oils, as well as the cytotoxic characteristics (against microorganisms and tumor cells) in in silico, in vitro and in vivo models for the sesquiterpenes and diterpenes that make up these oils.

Chemical variability of Copaifera langsdorffii Desf. from environmentally contrasting populations.

Copaifera langsdorffii Desf. is recognised as one of most famous medicinal and economic species of Copaiba, occurring in several distinct biomes. An untargeted metabolomic approach was used to evaluate the chemical variability of C. langsdorffii from contrasting climates biomes (Atlantic Rainflorest and the semiarid Cerrado). Metabolomic analysis enabled the identification of 11 compounds, including glycosylated flavonoids and galloylquinic acid derivatives. Multivariate analysis highlighted that Cerrado population had a significantly higher concentrations of galloylquinic acid derivatives in comparison to the rainforest biome. Meanwhile, Atlantic Rainforest populations presented higher content of flavonols. Semiarid biome, reduced the concentration of flavonoids, mainly concerning quercetin and kaempferol derivatives, however, in this biome flavonoids were more diverse. Both chemical classes presented relevance to be used as geographical origin chemical markers by qualitative and quantitative features.

Evaluation of Biocompatibility, Anti-Inflammatory, and Antinociceptive Activities of Pequi Oil-Based Nanoemulsions in In Vitro and In Vivo Models.

Pequi oil (Caryocar brasiliense) contains bioactive compounds capable of modulating the inflammatory process; however, its hydrophobic characteristic limits its therapeutic use. The encapsulation of pequi oil in nanoemulsions can improve its biodistribution and promote its immunomodulatory effects. Thus, the objective of the present study was to formulate pequi oil-based nanoemulsions (PeNE) to evaluate their biocompatibility, anti-inflammatory, and antinociceptive effects in in vitro (macrophages­J774.16) and in vivo (Rattus novergicus) models. PeNE were biocompatible, showed no cytotoxic and genotoxic effects and no changes in body weight, biochemistry, or histology of treated animals at all concentrations tested (90−360 µg/mL for 24 h, in vitro; 100−400 mg/kg p.o. 15 days, in vivo). It was possible to observe antinociceptive effects in a dose-dependent manner in the animals treated with PeNE, with a reduction of 27 and 40% in the doses of 100 and 400 mg/kg of PeNE, respectively (p < 0.05); however, the treatment with PeNE did not induce edema reduction in animals with carrageenan-induced edema. Thus, the promising results of this study point to the use of free and nanostructured pequi oil as a possible future approach to a preventive/therapeutic complementary treatment alongside existing conventional therapies for analgesia.

Pequi oil (Caryocar brasilense Cambess.) nanoemulsion alters cell proliferation and damages key organelles in triple-negative breast cancer cells in vitro.

Pequi oil is extracted from the fruit of a Brazilian native plant (Caryocar brasiliense Camb) that contains some molecules with anticancer potential. Due to its hydrophobic property, the administration of pequi oil associated with nanoemulsion systems represents a successful strategy to improve oil bioavailability. Breast cancer is the most frequent type of cancer among women and conventional therapies used are frequently associated with several side effects. Thus, the aim of this study was to investigate the effects of pequi oil-based nanoemulsion (PeNE) on triple-negative breast cancer cells (4T1), in vitro. PeNE presented a dose- and time-dependent cytotoxic effect with lower IC50 than free pequi oil after 48 h of exposure (p < 0.001). At 180 µg/mL, PeNE demonstrated numerous cell alterations, when compared to free pequi oil, such as morphological alterations, reduction in cell proliferation and total cell number, damage to plasmatic membrane, induction of lysosomal membrane permeability and depolarization of mitochondrial membrane, alteration of intracellular ROS production and calcium level, and increase in phosphatidylserine exposure. Taken together, the results suggest an interesting induction of cell death mechanisms involving a combined action of factors that impair nucleus, mitochondria, lysosome, and ER function. In addition, more pronounced effects were observed in cells treated by PeNE at 180 µg/mL when compared to free pequi oil, thereby reinforcing the advantages of using nanometric platforms. These promising results highlight the use of PeNE as a potential complementary therapeutic approach to be employed along with conventional treatments against breast cancer in the future.

In vivo Acute Anti-Inflammatory Activity of Essential Oils: A Review.

In recent years, there has been a significant increase in the search for new therapeutic strategies for the treatment of inflammatory diseases. In this sense, natural products emerge as a potential source for the discovery of new drugs, with the research of the pharmacological properties of these products being very important. In addition to its function in plants (insect attraction and repellency), essential oils present pharmacological effects, such as antibacterial, antifungal, antimutagenic, antiviral, antiprotozoal, antioxidant, antidiabetic and anti-inflammatory properties. In this review, we describe the mostly used in vivo acute inflammatory experimental models and the studies showing the in vivo anti-inflammatory activity of essential oils. Essential oil from species from the Apiaceae, Asteraceae, Burseraceae, Boraginaceae, Cupressaceae, Euphorbiaceae, Fabaceae, Lamiaceae, Lauraceae, Myrtaceae, Piperaceae, Poaceae, Rutaceae, Verbenaceae and Zingiberaceae families were described as being anti-inflammatory in vivo. Five models of acute inflammation are commonly used to investigate the anti-inflammatory activity in vivo: ear and paw edema, pleurisy, peritonitis and the subcutaneous air pouch model. In addition to in vivo analysis, ex vivo and in vitro experiments are carried out to study the anti-inflammatory action of essential oils. The most commonly used model was paw edema, especially due to this model being easy to perform. In order to suggest or elucidate the mechanisms involved in the anti-inflammatory effect, many studies measured some inflammatory mediators, such as cytokines, COX-2 expression and the levels of PGE2, and NO, or evaluated the effect of essential oils or their major compounds on inflammation response directly induced by inflammatory mediators.

Formulating Bioactive Terpenes.

Terpenes are specialized metabolites mainly produced by plants and are highly bioactive [...].

Amazonian Bacuri (Platonia insignis Mart.) Fruit Waste Valorisation Using Response Surface Methodology.

Bacuri (Platonia insignis Mart) is a species from the Clusiaceae genus. Its fruit pulp is commonly used in South America in several food products, such as beverages, ice cream and candies. Only the pulp of the fruit is used, and the peels and seeds are considered waste from these industries. As a trioxygenated xanthone source, this species is of high interest for bioproduct development. This work evaluated the mesocarp and epicarp of bacuri fruits through different extraction methods and experimental conditions (pH, temperature and solvent) in order to determine the most effective method for converting this agro-industrial waste in a value-added bioproduct. Open-column procedures and HPLC and NMR experiments were performed to evaluate the chemical composition of the extracts, along with total phenols, total flavonoids and antioxidant activities (sequestration of the DPPH and ABTS radicals). A factorial design and response surface methodology were used. The best extraction conditions of substances with antioxidant properties were maceration at 50 °C with 100% ethanol as solvent for mesocarp extracts, and acidic sonication in 100% ethanol for epicarp extracts, with an excellent phenolic profile and antioxidant capacities. The main compounds isolated were the prenylated benzophenones garcinielliptone FC (epicarp) and 30-epi-cambogin (mesocarp). This is the first study analysing the performance of extraction methods within bacuri agro-industrial waste. Results demonstrated that shells and seeds of bacuri can be used as phenolic-rich bioproducts obtained by a simple extraction method, increasing the value chain of this fruit.

Phytochemical composition, antisnake venom and antibacterial activities of ethanolic extract of Aegiphila integrifolia (Jacq) Moldenke leaves.

Snakebites are considered a major neglected tropical disease, resulting in around 100,000 deaths per year. The recommended treatment by the WHO is serotherapy, which has limited effectiveness against the toxins involved in local tissue damage. In some countries, patients use plants from folk medicines as antivenoms. Aegiphila species are common plants from the Brazilian Amazon and are used to treat snakebites. In this study, leaves from Aegiphila integrifolia (Jacq) Moldenke were collected from Roraima state, Brazil and its ethanolic extract was evaluated through in vitro and in vivo experiments to verify their antiophidic activity against Bothrops atrox crude venom. The isolated compounds from A. integrifolia were analyzed and the chemical structures were elucidated on the basis of infrared, ultraviolet, mass, 1H and 1³C NMR spectrometry data. Among the described compounds, lupeol (7), betulinic acid (1), ß-sitosterol (6), stigmasterol (5), mannitol (4), and the flavonoids, pectolinarigenin (2) and hispidulin (3), were identified. The ethanolic extract and flavonoids (2 and 3) partially inhibited the proteolytic, phospholipase A2 and hyaluronidase activities of B. atrox venom, and the skin hemorrhage induced by this venom in mice. Antimicrobial activity against different bacteria was evaluated and the extract partially inhibited bacterial growth. Thus, taken together, A. integrifolia ethanolic extract has promising use as an antiophidic and antimicrobial.

Ocotea complex: A metabolomic analysis of a Lauraceae genus.

The genus Ocotea is one of the largest and most economically explored in the Lauraceae family. However, its current industrial use is limited by the difficult identification of Ocotea species. At present, the genus is botanically considered a complex since accurate classification is very difficult to achieve based on taxonomic characteristics. As chemophenetics can aid in Ocotea species identification processes, we propose to evaluate the chemical data in several studies of Lauraceae species published between 1906 and 2019 in order to provide insights of the identification issue of matrix which DNA material or full morphological characteristics may not be readily available. Several alkaloids and lignoids have been found to be specifically synthesized by Ocotea species, enabling their usage in species identification by targeted and untargeted metabolomic approaches. The multivariate analysis of alkaloid, lignoid and flavonoid profiles allowed the characterization of subsets of species, the differentiation of chemical profile based on plant parts (leaves and branches), and to elucidate specific biomarkers for species. The previous chemophenetic model was contradicted by our data using statistical tools, such as HCPC, which allowed clustering adjustments based not only in the presence or absence of two single chemical classes. Chemophenetic study has proved to be a reliable tool in the enhancement of the identification and comprehension of this genus and the family. Here, the current status, pitfalls and future perspectives in Ocotea species metabolomic characterization will be presented.

Ocotea (Lauraceae) Amazonian essential oils chemical composition and their tyrosinase inhibition to use in cosmetics / Ocotea (Lauraceae) composición química de aceites esenciales amazónicos y su inhibición de la tirosinasa para usar en cosméticos

This study presents analyses on the chemistry, biology, pharmacology and chromatography of essential oils extracted from three species of the Ocotea genus: O. minor, O. ceanothifolia and O. leucoxylon. Leaves and stems, as well as the bark of O. minor, were processed using a modified Clevenger apparatus. Seven essential oils were obtained and analyzed using GC-FID and GC-MS, and their chemical compositions were determined. Assays of cytotoxicity, antioxidant and free radical scavenging activity, as well as tyrosinase and elastase inhibition were performed. In total, 25 constituents were identified, the principal being sesquiterpenes, such as spathulenol caryophyllene and its oxide. The oils did not present cytotoxicity using a hemolytic model, but also did not show antioxidant activity in the DPPH assay. Essential oil from stems of O. ceanothifolia, rich in spathulenol and caryophyllene oxide, demonstrated the capacity to inhibit 49.08% of tyrosinase activity at a concentration of 100 µg/mL. This research contributes to the chemical profile analysis of the three species of Ocoteathrough chemical investigations and biological activity, which are reported for the first time here in this study.

Este trabajo realiza un estudio químico, biológico, farmacológico y cromatográfico de aceites esenciales extraídos de tres especies del género Ocotea: O. minor, O. ceanothifoliay O. leucoxylon. Las hojas y tallos, así como la corteza de O. minor, se procesaron utilizando un aparato Clevenger modificado. Se obtuvieron siete aceites esenciales y se analizaron usando GC-FID y GC-MS, y se determinaron sus composiciones químicas. Se realizaron ensayos de citotoxicidad, actividad antioxidante y de atrapamiento de radicales libres, así como inhibición de tirosinasa y elastasa. En total, se identificaron 25 componentes, siendo los principales sesquiterpenos, como el spathulenol cariofileno y su óxido. Los aceites no presentaron citotoxicidad en un modelo hemolítico y tampoco mostraron actividad antioxidante en el ensayo con DPPH. El aceite esencial de tallos de O. ceanothifolia, rico en espatulenol y óxido de cariofileno, mostró capacidad para inhibir el 49.08% de la actividad de tirosinasa a una concentración de 100 µg/mL. Esta investigación contribuye al análisis del perfil químico de las tres especies de Ocotea a través de investigaciones químicas y actividad biológica la cual se informan por primera vez.

Essential Oils and Isolated Terpenes in Nanosystems Designed for Topical Administration: A Review.

Essential oils are natural products with a complex composition. Terpenes are the most common class of chemical compounds present in essential oils. Terpenes and the essential oils containing them are widely used and investigated by their pharmacological properties and permeation-enhancing ability. However, many terpenes and essential oils are sensitive to environmental conditions, undergoing volatilization and chemical degradation. In order to overcome the chemical instability of some isolated terpenes and essential oils, the encapsulation of these compounds in nanostructured systems (polymeric, lipidic, or molecular complexes) has been employed. In addition, nanoencapsulation can be of interest for pharmaceutical applications due to its capacity to improve the bioavailability and allow the controlled release of drugs. Topical drug administration is a convenient and non-invasive administration route for both local and systemic drug delivery. The present review focuses on describing the current status of research concerning nanostructured delivery systems containing isolated terpenes and/or essential oils designed for topical administration and on discussing the use of terpenes and essential oils either for their biological activities or as permeation enhancers in pharmaceutic formulations.

Biological Activities and Cytotoxicity of Eperua oleifera Ducke Oil-resin.

BACKGROUND: The oil-resin of Eperua oleifera Ducke has been used in popular medicine similarly to the copaiba oil (Copaifera spp.). OBJECTIVE: This study aimed to investigate the effects of the acid fraction of E. oleifera oil-resin (AFEOR) on cell proliferation, collagen production in human fibroblasts, inhibition of metalloproteinases, and cytotoxicity against tumor cell lines. MATERIALS AND METHODS: Acid fraction of E. oleifera was fractionated in the ion exchange column chromatography. Cytotoxicity and genotoxicity were evaluated by Alamar Blue® and Cometa assay. The inhibition of metalloproteinases was performed by zymography and Western blotting. RESULTS: The predominant acidic diterpenes in the AFEOR were copalic and hardwickiic acids. AFEOR caused morphology alteration and decrease of proliferation at concentrations higher than 5 µg/mL. It also caused significant collagen proliferation in fibroblasts. It showed cytotoxicity against tumoral and nontumoral cell lines, with IC50 values ranging from 13 to 50 µg/mL, and a hemolytic activity with an IC50 value of 38.29 µg/mL. AFEOR inhibited collagenase activity, with an IC50 value of 46.64 µg/mL, and matrix metalloproteinase-2 (MMP)-2 and MMP-9 in HaCaT cells or MMP-1 expression in MRC-5 cells. AFEOR induced genotoxicity in MRC-5 cells with a DNA damage index between 40% and 60% when compared to the negative controls (0%-20%). CONCLUSION: For the first time, biological activities from oil-resin E. oleifera demonstrated ratifying somehow its popular use. SUMMARY: Analysis of crude oil-resin and fractionation of diterpenic fraction was performance using selective ion-exchange column chromatographyCytotoxicity analysis and morphology were performed with different cell linesCollagen production in human fibroblasts, inhibition of metalloproteinases were demonstrated by zymography and Western blotting. Abbreviations used: AFEOR: Eperua oleifera oil-resin.

Development and evaluation of an inhalation chamber for in vivo tests

ABSTRACT The bioavailability, toxicity, and therapeutic efficacy of a drug is directly related to its administration route. The pulmonary route can be accessed by inhalation after fumigation, vaporization or nebulization. Thus, pharmacological and toxicological evaluation accessed by an apparatus specifically designed and validated for this type of administration is extremely important. Based on pre-existing models, an inhalation chamber was developed. This presents a central structure with five animal holders. The nebulized air passes directly and continuously through these holders and subsequently to an outlet. Evaluation of its operation was performed using clove essential oil, a nebulizer, and a flow meter. The air within the chamber was collected by static headspace and analyzed by gas chromatography with a flame ionization detector. For this purpose, a 2.5 minutes chromatographic method was developed. The air flow in each of the five outputs was 0.92 liters per minute. During the first minute, the chamber became saturated with the nebulized material. Homogeneous and continuous operation of the chamber was observed without accumulation of volatile material inside it for 25 minutes. The inhalation chamber works satisfactorily for in vivo tests with medicines designed to be administrated by inhalation.

Physicochemical Characterization and Biological Activities of the Triterpenic Mixture α,ß-Amyrenone.

α-Amyrenone and ß-amyrenone are triterpenoid isomers that occur naturally in very low concentrations in several oleoresins from Brazilian Amazon species of Protium (Burseraceae). This mixture can also be synthesized by oxidation of α,ß-amyrins, obtained as major compounds from the same oleoresins. Using a very simple, high yield procedure, and using a readily commercially available mixture of α,ß-amyrins as substrate, the binary compound α,ß-amyrenone was synthesized and submitted to physico-chemical characterization using different techniques such as high-performance liquid chromatography, nuclear magnetic resonance (¹H and 13C), mass spectrometry, scanning electron microscopy, differential scanning calorimetry, thermogravimetry and derivative thermogravimetry, and Fourier transform infrared spectroscopy (FTIR). Biological effects were also evaluated by studying the inhibition of enzymes involved in the carbohydrate and lipid absorption process, such as α-amylase, α-glucosidase, lipase, and their inhibitory concentration values of 50% of activity (IC50) were also determined. α,ß-Amyrenone significantly inhibited α-glucosidase (96.5% ± 0.52%) at a concentration of 1.6 g/mL. α,ß-Amyrenone, at a concentration of 100 µg/mL, showed an inhibition rate on lipase with an IC50 value of 82.99% ± 1.51%. The substances have thus shown in vitro inhibitory effects on the enzymes lipase, α-glucosidase, and α-amylase. These findings demonstrate the potential of α,ß-amyrenone for the development of drugs in the treatment of chronic metabolic diseases.

Trypanocidal activity of the compounds present in Aniba canelilla oil against Trypanosoma evansi and its effects on viability of lymphocytes.

Aniba canelilla (H.B.K.) Mez, popularly known as "casca-preciosa" (precious bark), is a plant of the Lauraceae family, widely distributed in the Amazon region. Its major constituent is 1-nitro-2-phenylethane, a rare molecule in plants which is responsible for this plant's cinnamon scent. The present study aimed to report the chemical characterization of the oil extracted from Aniba canelilla using gas-chromatography/mass spectrometry and to assess its in vitro trypanocidal activity against Trypanosoma evansi, a prevalent haemoflagellate parasite that affects a broad range of mammal species in Africa, Asia and South America. The oil presented 1-nitro-2-phenylethane (83.68%) and methyleugenol (14.83%) as the two major components. The essential oil as well as both major compounds were shown to exert trypanocidal effect. Methyleugenol was slightly more active than 1-nitro-2-phenylethane. In vitro studies showed that the oil extracted from the stems of A. canelilla may be regarded as a potential natural treatment for trypanosomosis, once proven their in vivo action, may be an interesting alternative in the treatment of infected animals with T. evansi.

Antibacterial Activity of Copaiba Oil Gel on Dental Biofilm.

UNLABELLED: Amazonian biodiversity products that have been used for years in folk medicine, have emerged as feasible and promising alternatives for the inhibition of microorganisms in dental biofilm. Copaiba oil, a phytotherapic agent widely used by the Amazonian populations, is known for its antibacterial, anti-inflammatory, anesthetic, healing and antitumor medicinal properties. OBJECTIVE: The aim of this study was to evaluate the in vitro antibacterial activity of copaiba oil (Copaifera multijuga) gel against strains of Streptococcus sp present in dental biofilm. MATERIALS AND METHODS: The copaiba oil was obtained and the chemical components were identified. The oil emulsions were formulated and used with the Brain Heart Infusion agar diffusion method with strains of Streptococcus mitis, Streptococcus constellatus and Streptococcus salivarius isolated from patients as well as standard strains of S. mitis (ATCC903), S. mutans (ATCC10449), S. sanguinis (ATCC15300) and S. oralis (ATCC10557). The study groups were as follows: experimental copaiba oil gel, 1% chlorhexidine gel (positive control) and base gel (negative control). The seeded plates were incubated at 37ºC for 12, 24 and 48 hours, respectively. The results obtained were analyzed by Shapiro-Wilk and Friedman Tests (p<0.05) for non parametric data and the Tukey test was used for pH values with 5% level of significance. RESULTS: The experimental copaiba oil gel and 1% chlorhexidine gel showed antibacterial activity against the tested microorganisms. CONCLUSION: The copaiba oil gel demonstrated antibacterial activity against all the strains of Streptococcus sp tested, suggesting that it can be used for dental biofilm control.

Pleurodesis induction in rats by Copaiba (Copaifera multijuga Hayne) oil.

This study aims to assess and compare copaiba oleoresin of Copaifera multijuga and 0.5% silver nitrate for the induction of pleurodesis in an experimental model. Ninety-six male Wistar rats were divided into three groups: control (0.9% saline solution), copaiba (copaiba oil), and silver nitrate (0.5% silver nitrate). The substances were injected into the right pleural cavity and the alterations were observed macroscopically and microscopically at 24, 48, 72, and 504 h. The value of macroscopic alterations grade and acute inflammatory reaction grade means was higher in the 24 h copaiba group in relation to silver nitrate. Fibrosis and neovascularization means in the visceral pleura were higher in 504 h copaiba group in relation to the silver nitrate group. The grade of the alveolar edema mean was higher in the silver nitrate group in relation to the copaiba group, in which this alteration was not observed. The presence of bronchopneumonia was higher in the 24 h silver nitrate group (n = 4) in relation to the copaiba group (n = 0). In conclusion, both groups promoted pleurodesis, with better results in copaiba group and the silver nitrate group presented greater aggression to the pulmonary parenchyma.

Composição de óleos essenciais de Dicypellium manausense, Mezilaurus duckei, Mezilaurus itauba e Pleurothyrium vasquezii, quatro espécies amazônicas da família Lauraceae / Composición de aceites esenciales de Dicypellium manausense, Mezilaurus duckei, Mezilaurus itauba y Pleurothyrium vasquezii, cuatro especies de Lauraceae de amazónia / Você quis dizer: Composição de óleos essenciais de Dicypellium manauense, Mezilaurus duckei, Mezilaurus itauba e Pleurothyrium vasquezii, quatro espécies amazônicas da família Lauraceae Composition of essential oils manausense Dicypellium, Mezilaurus duckei, Mezilaurus Itauba and Pleurothyrium vasquezii four Amazonian species of the Lauraceae family

Essential oils obtained from the aerial parts of Dicypellium manausense, Mezilaurus duckei, Mezilaurus itauba and Pleurothyrium vasquezii collected at the Ducke Forest Reserve (Manaus, Brazil) were obtained by hydrodistillation and analyzed by CG-FID and GC-MS. Essential oil yields ranged from 0.1 to 0.2 percent (w/w of dry material). The major components were beta-caryophyllene in the leaves of D. manausense (39.5 percent), leaves and branches of M. duckei (32.6 and 18.4 percent, respectively) and branches of M. itauba (51.8 percent); and germacrene D in the leaves of D. manausense (6.7 percent), branches of M. itauba (9.1 percent) and leaves and branches of P. vasquezii (15.6 and 8.0 percent, respectively). This paper describes for the first time the composition of these essential oils.

Os óleos essenciais obtidos das partes aéreas de Dicypellium manausense, Mezilaurus duckei, Mezilaurus itauba e Pleurothyrium vasquezii coletadas na Reserva Florestal Ducke (Manaus, Brasil) foram obtidos por hidrodestilação e analisados por CG-DIC e CG-EM. Os rendimentos dos óleos variaram de 0,1 a 0,2 por cento (m/m de material seco). Os principais componentes foram beta-cariofileno nas folhas de D. manausense (39,5 por cento), folhas e galhos de M. duckei (32,6 e 18,4 por cento, respectivamente) e galhos de M. itauba (51,8 por cento) e germacreno D na folhas de D. manausense (6,7 por cento), galhos de M. itauba (9,1 por cento) e folhas e galhos de P. vasquezii (15,6 e 8,0 por cento, respectivamente). Este trabalho descreve pela primeira vez a composição desses óleos.

Toxicity of oleoresins from the genus Copaifera in Trypanosoma cruzi: a comparative study.

Several members of the genus Copaifera are present in Latin America, mainly in the Amazon region. These plants produce oleoresins that are used by indigenous people for medicinal purposes, with no distinction among species. Their medicinal properties include the treatment of cutaneous ulcerations associated with leishmaniasis and wounds caused by insect bites. However, to date, no comparative studies of the antiparasitic activity of copaiba oleoresins from different species against Trypanosoma cruzi have been published. In the present study, copaiba oleoresins from eight species were evaluated for activity against T. cruzi, including observations of cytotoxic effects in mammalian cells and parasite cells. All of the copaiba oleoresins exerted effects on all parasite life stages, especially against the replicative forms. C. martii and C. officinalis exhibited the best activity. For intracellular amastigotes, the IC50 values varied from less than 5.0 µg/mL to 10.0 µg/mL. For epimastigotes and trypomastigotes, the maximum inhibition was obtained with IC50 values of 17.0 µg/mL and 97.0 µg/mL, respectively. Oleoresins showed moderate cytotoxicity to nucleated cells, 17.5 to 32.5 µg/mL being the concentration range needed to reduce the monolayer integrity by 50 %. Toxicity to erythrocytes was observed by a hemolytic effect of 50 % above 500 µg/mL for half of the oleoresins from different species. Different oleoresins caused lipid peroxidation, increased cell-membrane permeability and changed the mitochondrial potential. Ultrastructural changes were observed after the treatment of the intracellular amastigote forms of the parasite. The toxic potential differed among oleoresins from distinct copaiba species, which can influence medicinal efficacy. This is especially relevant for people who live far from medical assistance and depend on medicinal plants.