Validation of an analytical method by HPLC for the quantification of yangambin from the Ocotea duckei species / Validación de un método analítico por HPLC para la cuantificación de yangambin de la especie Ocotea duckei

Ocotea duckei , known as Louro - de - cheiro, belongs to the Lauraceae family and presents lignoid yangambine (YAN) as the main plant marker. This work aimed to develop and validate an analytical method by high performance liquid chromatography for the quantification of YAN. The sample used was the crude eth anolic extract (CEE) obtained from aerial parts. In the developed method, a C18 column was used. The mobile phase was composed of acetonitrile and water (45:55), whereas the method parameters included mobile phase flow rate at 0.8 mL/min, oven temperature at 40°C, and monitoring at 205 nm. In the validation, the parameters of selectivity, linearity, precision, accuracy, robustness, limits of detection and quantification were evaluated. As a result, the developed method is in accordance with the guidelines f or validation of analytical methods and presented satisfactory chromatographic parameters for YAN determination. Thus, the present analytical methodology can be applied in the quality control of O. duckei raw materials.

Ocotea duckei , conocida como Louro - de - cheiro, pertenece a la familia Lauraceae y presenta la yangambina lignoide (YAN) como principal marcador vegetal. Este trabajo tuvo como objetivo desarrollar y val idar un método analítico por cromatografía líquida de alta resolución para la cuantificación de YAN. La muestra utilizada fue el extracto etanólico crudo (EEC) obtenido de partes aéreas. En el método desarrollado se utilizó una columna C18. La fase móvil c onsistió en acetonitrilo y agua (45:55), mientras los parámetros del método incluyeron el caudal de la fase móvil a 0,8 m L /min, la temperatura del horno a 40°C y la monitorización a 205 nm. En la validación se evaluaron los parámetros de selectividad, line alidad, precisión, exactitud, robustez, límites de detección y cuantificación. Como resultado, el método desarrollado está de acuerdo con las pautas para la validación de métodos analíticos y presentó parámetros cromatográficos satisfactorios para la deter minación de YAN. Por lo tanto, la presente metodología analítica se puede aplicar en el control de calidad de las materias primas de O. duckei.

Biological activities of essential oils from six genotypes of four Ocotea species

Abstract Essential oils from four Ocotea species collected in southern Brazil were evaluated for chemical composition using gas chromatography coupled with mass spectrometry. The primary compound identified in O. acutifolia essential oil was an unsaturated tetracyclic diterpene, phyllocladene (67.7%), followed by a sesquiterpene hydrocarbon, ß-selinene (18.0%). The sesquiterpene fraction was predominant in oils from two collections of O. puberula; ß-caryophyllene (25.2%) and globulol (22.6%) were the major compounds identified in collections 1 and 2, respectively. O. silvestris essential oil contained predominantly germacrene D and bicyclogermacrene. These compounds were also predominant in essential oil from O. indecora leaves collected from shady habitats. By contrast, essential oil extracted from O. indecora grown under direct sunlight contained mainly oxygenated sesquiterpenes, such as guaiol (30.2%), α-eudesmol (27.6%), and ß-eudesmol (12.7%). Chemotaxis assays showed that Ocotea essential oils had no significant inhibitory activity on leukocyte migration compared with a chemotactic stimulant (lipopolysaccharide from Escherichia coli). However, the oils exhibited antifungal activity against Candida parapsilosis, with a minimum inhibitory concentration of 500 µg/mL. To our knowledge, this is the first study to investigate the in vitro antifungal and antichemotactic activities of essential oils from Ocotea species native to southern Brazil

Preliminary evaluation of the larvicidal activity of extracts and fractions from Ocotea nutans (Nees) Mez against Aedes aegypti

Abstract INTRODUCTION: Aedes aegypti is the main vector of dengue and yellow fever. Recently, the use of plant-sourced larvicides has gained momentum. METHODS: The hydroethanolic extracts and fractions ofOcotea nutansleaves and stems were bioassayed to determine the larvicidal efficacy of these samples. RESULTS: S-HEX (hexane fraction from the crude stem extract) demonstrated high potential for controlling third-stage larvae, with an LC50 of 14.14 µg.mL-1 (concentration required to inhibit 50% of the treated larvae). CONCLUSIONS Extracts from O. nutans were effective against third-stage larvae ofA. aegyptiafter 24 h of exposure.

Ocotea daphnifolia: phytochemical investigation, in vitro dual cholinesterase inhibition, and molecular docking studies

This study aimed to evaluate the anticholinesterase activities of extracts and fractions of Ocotea daphnifolia in vitro and characterize its constituents. The effects of hexane, ethyl acetate, and ethanolic extracts on acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE) activity were determined with a spectrophotometry assay. All extracts inhibited cholinesterase activity, and the ethanolic extract (2 mg/mL) exhibited the highest inhibition of both enzymes (99.7% for BuChE and 82.4% for AChE). The ethanolic extract was fractionated by column chromatography resulting in 14 fractions that were also screened for their anticholinesterase effects. Fraction 9 (2 mg/mL) showed the highest activity, inhibiting AChE and BuChE by 71.8% and 90.2%, respectively. This fraction was analyzed by high-performance liquid chromatography high-resolution mass spectrometry which allowed the characterization of seven glycosylated flavonoids (containing kaempferol and quercetin nucleus) and one alkaloid (reticuline). In order to better understand the enzyme-inhibitor interaction of the reticuline toward cholinesterase, molecular modeling studies were performed. Reticuline targeted the catalytic activity site of the enzymes. Ocotea daphnifolia exhibits a dual cholinesterase inhibitory activity and displays the same pattern of intermolecular interactions as described in the literature. The alkaloid reticuline can be considered as an important bioactive constituent of this plant.

Ocotea pulchellaas an alternative against schistosomiasis: chemical analysis, development of nanoemulsion and biological control activity / Ocotea pulchellacomo una alternativa ante esquistosomiasis: análisis químico, desarrollo de una nanoemulsión y actividad en control biológico

The aim of this work was to evaluate the potential of the essential oil (EO) from Ocotea pulchella leaves as an alternative in the control of schistosomiasis. It was tested O. pulchella EO nanoformulation to assess its activity against adult Biomphalaria glabrata, their spawning and Schistossoma mansoni cercariae. Additionally, the EO chemical composition was investigated by gas-chromatography. Nanoemulsion were elaborated by the low energy method. The adult mollusks, their spawning and cercariae were placed in contact with nanoemulsion to calculate lethal concentrations. Myristicin, bicyclogermacrene and α-Pinene were the main substances in the EO. Nanoemulsion caused mortality of adult B. glabrata, its egg embryos and S. mansoni. These results suggest the use of this nanoemulsion as an alternative in the control of the schistosomiasis cycle.

El objetivo de este trabajo fue evaluar el potencial de los aceites esenciales (AE) de las hojas de Ocotea pulchellacomo una alternativa en el control de esquistosomiasis. Se probó una nanoformulación de AE de O. pulchellapara evaluar su actividad ante adultos de Biomphalaria glabrata, sus huevos y cercarías de Schistossoma mansoni. La nanoemulsión fue elaborada por el método de baja energía. Los moluscos adultos, sus huevos y cercarías se colocaron en contacto con la nanoemulsión para calcular concentraciones letales. Los compuestos mayoritarios en el AE fueron miristicina, biciclogermacreno y α-pineno. La nanoemulsión causó mortalidad en adultos de B. glabrata, sus huevos y a S. mansoni. Los resultados sugieren el uso de esta nanoemulsión como una alternativa en el control del ciclo de esquistosomiasis.

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.

Chemical composition and acaricidal activity of Ocotea notata (Lauraceae), an endemic species from Brazil, against the cattle tick Rhipicephalus microplus / Composición química y actividad acaricida de Ocotea notata (Lauraceae), una especie endémica de Brasil, contra la garrapata del ganado Rhipicephalus microplus

Rhipicephalus microplus, is one parasites that cause severe productivity losses in the cattle industry of Brazil and shows increasing resistance to conventional pesticides. This research aims to study the chemical composition, and acaricidal activity of the essential oil from Ocotea notata leaves, a brazilian endemic species, against R. microplus. The effect on R. microplus engorged adult females was evaluated using the immersion test. The oil reduced the survival by 90% after incubation for 15 days and there was 100% reduction for posture inhibition and reproductive capacity. These results suggest that the O. notata essential oil has activity on the R. microplus.

Rhipicephalus microplus, es un parásito que causa graves pérdidas de productividad en la industria ganadera de Brasil y muestra una creciente resistencia a los pesticidas convencionales. Esta investigación tiene como objetivo estudiar la composición química y la actividad acaricida del aceite esencial de las hojas de Ocotea notata, una especie endémica brasileña, contra R. microplus. El efecto sobre las hembras adultas engordadas de R. microplus se evaluó mediante la prueba de inmersión. El aceite redujo la supervivencia en 90% después de la incubación durante 15 días y hubo una reducción del 100% para la inhibición de la postura y la capacidad reproductiva. Estos resultados sugieren que el aceite esencial de O. notata tiene actividad contra R. microplus.

Composition, antioxidant properties, and biological activities of the essential oil extracted from Ocotea diospyrifolia (Meisn.) Mez

The article has aimed to characterize the essential oil extracted from Ocotea diospyrifolia (Meisn.) Mez. leaves, in terms of its chemical composition and antioxidant, hemolytic, and phytotoxic potentials, as well as its toxicity against Artemia salina. The major constituents identified by CG-MS were d-elemene, spathulenol, and b-atlantol. When screened for potential biological activities, the essential oil presented low toxicity against Artemia salina, and a capacity of lysing red blood cells. Also, the evaluation of its in vitro antioxidant activity, using the phosphomolybdenum method, showed better results when compared to butylhydroxytoluene (BHT) and rutin. In conclusion, the results obtained showed certain in vitro toxicity, leading to an interesting target for cytotoxicity evaluations of carcinoma cells.

Crecimiento de Ocotea cernua (Lauraceae) en bosques aluviales inundables de la Amazonía peruana / Growth of Ocotea cernua (Lauraceae) in Peruvian Amazon floodplain forests

Ocotea cernua (Nees) Mez, "moena negra", es una especie comercial que se desarrolla en los bosques del llano aluvial inundable de la Amazonía peruana. Este estudio, proporciona información sobre su crecimiento, y que puede utilizarse en el manejo de la especie. Se analizó la abundancia y estructura de O. cernua en nueve parcelas permanentes (100 m x 100 m) y 24 transectos (40 m x 100 m). El análisis de los registros sobre crecimiento en diámetro, mostró que el incremento anual medio y el incremento anual máximo, alcanzan un valor máximo de 9.5 y 17.4 mm/año, ambos en la clase diamétrica de 25 a 30 cm. Tomando como base ambos incrementos, el tiempo necesario para que un árbol alcance diámetros >30 cm DAP, sería de 60 y 34 años, respectivamente. Basado en factores de competencia entre árboles, el modelo de crecimiento ajustado estima que la tasa máxima de crecimiento en diámetro anual es 2.10, 1.28 y 0.50 cm para árboles con baja, media y alta competencia. Esta tasa máxima de crecimiento ocurre cuando los árboles cuentan con DAP que oscilan entre 21.10, 20.28 y 20.50 cm, para baja, media y alta competencia, respectivamente; sin embargo, el tiempo que requiere un árbol para obtener dichos diámetros varía enormemente, con valores de 12.31 cm para baja competencia, 20.35 para media competencia y 54.51 años para alta competencia.

Ocotea cernua (Nees) Mez "moena negra" is a commercial species that thrives in alluvial floodplain forests in the Peruvian Amazon. This study presents information about diameter growth of O. cernua and provides useful information for its forest management. The stand density and structure was analysed in nine permanent sample plots (100 m x 100 m) and 24 transects (40 m x 100 m). Analysis of tree diameters at different time indicates maximum values of 9.5 and 17.4 mm/year for the average annual diameter increment and the maximum annual diameter increment respectively; both into 25 ‒ 30 cm diameter classes. Considering this increments, a tree will reach a diameter higher than 30 cm DAP, in 60 to 34 years respectively. Estimations of the adjusted model showed the maximum annual growth increment estimated in 2.10, 1.28 and 0.50 cm for trees with low, medium and high competition, corresponding to trees with DBHs of 21.10, 20.28 and 20.50 cm for trees with low, medium and high competition, respectively. However, the time required to reach such diameters is highly variable with values of 12.31, 20.35 and 54.51 years, respectively.

Medicinal properties of Ocotea bullata stem bark extracts: phytochemical constituents, antioxidant and anti-inflammatory activity, cytotoxicity and inhibition of carbohydrate-metabolizing enzymes / 中西医结合学报

<p><b>OBJECTIVE</b>This study evaluates the phytochemical constituents, antioxidant and anti-inflammatory activity, cytotoxicity, and inhibitory activity against carbohydrate metabolism of extracts from Ocotea bullata stem bark.</p><p><b>METHODS</b>Hexane, ethyl acetate, methanol and water were used to extract the air-dried sample. The phytochemical investigation and antioxidant assays were carried out on the extracts using standard procedures. The antidiabetic and anti-inflammatory potentials were evaluated using α-amylase, α-glucosidase and 5-lipoxygenase enzymes respectively. Vero cells were employed to determine the cytotoxicity of the extracts.</p><p><b>RESULTS</b>The ethyl acetate extract showed higher phenolic contents (8.97 mg/g gallic acid) while methanol displayed higher flavonoid (36.06 mg/g quercetin) and flavonol (153.44 mg/g rutin) contents than other extracts. Hexane extract had the greatest capacity to scavenge 1,1-diphenyl-2-picryl-hydrazyl (0.19 mg/mL), hydroxyl (25.77 mg/mL) and 2,2-azino-bis(3-ethylbenzothiazoline)-6-sulfonic acid (0.07 mg/mL) radicals, while ethyl acetate extract exhibited stronger inhibition (P < 0.05) against superoxide anion (0.41 mg/mL) and ferric ion-reducing power (2.36 mg/mL) compared to other extracts and standards. Aqueous extract (27.02 mg/mL) exhibited strong metal-chelating activity (P < 0.05) compared to other extracts and gallic acid. The aqueous extract demonstrated the greatest inhibition of α-glucosidase (1.45 mg/mL) and α-amylase (2.43 mg/mL) compared to other extracts and acarbose. There were no significant differences (P < 0.05) in half-maximum inhibitory concentration (IC) values of all tested extracts and indomethacin in the inhibition of 5-lipoxygenase activity. The aqueous extract was nontoxic to Vero cells with an ICvalue of 0.38 mg/mL.</p><p><b>CONCLUSION</b>O. bullata stem bark contains active phytochemicals with diverse pharmacological potentials that could be beneficial in managing diabetes and inflammation.</p>

Chemical composition of essential oil from leaves of Ocotea limae Vattimo Gil. and Ocotea gardneri (Meisn. ) Mez. growing wild in Atlantic forest of North-Eastern Brazil / [Composición química del aceite esencial de las hojas de Ocotea limae Vattimo Gil. y Ocotea gardneri (Meisn. ) Mez. nativas de la floresta Atlántica del Nordeste de Brasil

Essential oils from leaves of Ocotea limae and Ocotea gardneri species were analyzed by GC-FID and GC-MS. The analysis revealed the presence of 48 components accounting for 98.1 ± 1.3% e 98.0 ± 0.5% of the essential oils from the O. limae and O. gardneri, respectively. The oils were characterized by high percentage of sesquiterpenes. The mains compounds identified in the essential oils were spathulenol (13.3 ± 0.5%), ß-caryophyllene (12.4 ± 0.5%), bicyclogermacrene (11.3 ± 0.4%) and germacrene D (10.9 ± 0.3%) from the O. limae and germacrene D (26.9 ± 0.9%) e bicyclogermacrene (21.7 ± 0.7%) from the O. glomerata.

Los aceites esenciales de hojas de Ocotea limae y Ocotea gardneri fueron analizados por GC-FID y GC-MS. El análisis reveló la presencia de 48 componentes que representan 98,1 ± 1,3% y 98,0 ± 0,5% de los aceites esenciales de O. limae y O. gardneri, respectivamente. Los aceites se caracterizaron por un alto porcentaje de sesquiterpenos. Los principales compuestos identificados en los aceites esenciales fueron espatulenol (13,3 ± 0,5%), ß-cariofileno (12,4 ± 0,5%), biciclogermacreno (11,3 ± 0,4%) y germacreno D (10,9 ± 0,3%) de O. limae y germacreno D (26,9 ± 0,9%) y bicyclogermacreno (21,7 ± 0,7%) de la O. glomerata.

Comparative toxicity of essential oil and blends of selected terpenes of Ocotea species from Pernambuco, Brazil, against Tetranychus urticae Koch

ABSTRACT Essential oils from the leaves of two species of the genus Ocotea that occur in the Atlantic Forest in the state of Pernambuco, Brazil, were analyzed using gas chromatography-mass spectrometry. The acaricidal activity of these oils as well as 11 selected components and blends were evaluated in fumigation and residual contact tests against the two-spotted spider mite (Tetranychus urticae). Sixty-seven constituents were identified, totaling 97.3 ± 0.3% and 97.8 ± 0.5% of the oils from O. duckei and O. glomerata, respectively. Sesquiterpene was the dominant class. The compounds β-caryophyllene (18.6 ± 0.1%) and aromadendrene (17.3 ± 0.6%) were the main constituents of the oils from O. duckei and O. glomerata, respectively. Acaricidal action varied depending on the method employed, species and chemical nature of the selected constituents. The mites were susceptible to the oils and chemical constituents using the fumigation method. The O. duckei oil was respectively 2.5-fold and 1.5-fold more toxic than the O. glomerata oil using the fumigation and residual contact methods. Among the selected constituents, β-caryophyllene was the most toxic, independently of the method employed. The individual toxicity of the selected compounds and their blends as well as the role of these constituents in the overall toxicity of the essential oils are also discussed.

Chemical composition, antioxidant and biological activity of Ocotea bicolor Vattimo-Gil (LAURACEAE) essential oil

ABSTRACT The essential oil composition of the Ocotea bicolor, native plant of Brazil, was studied for the first time. The essential oil of the leaf was obtained by hydrodistillation and analyzed by GC/MS. The analytical procedure revealed a predominance of sesquiterpenes, δ-cadinene (7.39%), ß-sesquiphellandrene (6.67%), ß-elemene (5.41%) and α-cadinol (5,23%). The essential oil was submitted to brine shrimp toxicity evaluation, antioxidant and antibacterial tests. The antioxidant activity by the formation of phosphomolybdenum complex method presented positive results. The minimum inhibitory concentration (MIC) values were higher than 1000 µg/mL for the microorganisms tested. Toxicity activity revealed LC50 results of 40.10 (µg/mL), being toxic to the organisms in this study

Composición química del aceite esencial de Ocotea cymbarum Kunth (cascarillo y/o sasafrás) de la región Orinoquia / Chemical composition of essential oil of Ocotea cymbarum Kunth (cascarilla and/or sassafras) from the Orinoquía region

Introducción: en algunas poblaciones de la Orinoquia colombiana y/o venezolana venden, en plazas de mercado, los aceites de cascarillo y sasafrás; estos aceites son empleados para aliviar dolencias como artritis reumática, afecciones respiratorias y tratar picaduras de insectos y animales ponsoñosos. Los productos se obtienen de la especie Ocotea cymbarum Kunth, la cual tiene una abundante sinonimia botánica como Alseodaphne cymbarum,Licaria cymbarum, Misanteca cymbarum, Nectandra barcellensis, Nectandra cymbarum, Nectandra elaiophora, Nectandra oleífera y Ocotea barcellensis. Objetivo: realizar un análisis comparativo de las características fisicoquímicas del aceite esencial de cascarillo y/o sasafrás (posible Ocotea cymbarum Kunth). Métodos: la composición química relativa de los aceites obtenidos de madera y corteza fue determinada mediante cromatografía de gases acoplada a espectrometría de masas (CG-EM), el cálculo y comparación de índices de retención en columnas de polaridad ortogonal y la comparación de los espectros de masas por impacto electrónico con los de las bases de datos NIST08.L, Wiley9.L. Resultados: fueron determinados 45 compuestos en las muestras analizadas y más del 90 por ciento de la composición relativa establecida para cada aceite corresponde a compuestos monoterpénicos principalmente alcanfor y alfa-terpineol. Al realizar un análisis de las rutas biosintéticas que conducen a la generación de los principales compuestos detectados en los aceites analizados, se evidenció que las especies de donde se obtuvieron estos aceites, presentan diferentes grados de evolución micromolecular. Conclusión: los aceites de cascarillo y sasafrás provienen de especies vegetales con diferentes grados de evolución química. Este resultado refuerza la evidencia de la alta diversidad biológica de la familia Lauraceae. El trabajo fue realizado con el apoyo financiero del Laboratorio de Productos Naturales Vegetales del departamento de Química de la Universidad Nacional de Colombia sede Bogotá(AU)

Introduction: cascarilla and sassafras oils are sold in market places of some settlements in the Colombian and/or Venezuelan Orinoquía. These oils are used to alleviate conditions such as rheumatoid arthritis and respiratory disorders, and to treat the bites of insects and poisonous animals. The oils are obtained from the species Ocotea cymbarum Kunth, which displays abundant botanical synonymy as Alseodaphne cymbarum, Licaria cymbarum,Misanteca cymbarum, Nectandra barcellensis, Nectandra cymbarum, Nectandra elaiophora, Nectandra oleífera and Ocotea barcellensis. Objective: carry out a comparative analysis of the physicochemical characteristics of essential oil of cascarilla and/or sassafras (Ocotea cymbarum Kunth).Methods: the relative chemical composition of oils obtained from wood and bark was determined by gas chromatography coupled with mass spectrometry (GC-MS). Estimation and comparison of retention indices was conducted with orthogonal polarity columns. Comparison of electron impact mass spectra was performed with the databases NIST08.L and Wiley9.L. Results: forty-five compounds were determined from the samples analyzed. More than 90 percent of the relative composition established for each oil corresponds to monoterpenic compounds, mainly camphor and alpha-terpineol. Analysis of the biosynthetic pathways leading to the generation of the main compounds detected in the oils studied, showed that the species from which the oils were obtained exhibit varying degrees of micromolecular evolution. Conclusion: cascarilla and sassafras oils are obtained from plant species at varying stages of chemical evolution. This result constitutes additional evidence of the great biological diversity of the Lauraceae family. The study was conducted with financial support from the Natural Plant Products Laboratory of the Chemistry Department at the National University of Colombia at Bogotá(AU)

Chemical composition and antimicrobial activity of the essential oil of the leaves of ocotea caudata (nees) mez (lauraceae) from Colombia / Composición química y actividad antimicrobiana del aceite esencial de las hojas de ocotea caudata (nees) mez(lauraceae) de Colombia

Ocotea is a genus that belong to Lauraceae family, which has about 56 species, distributed in Asia, Africa and mainly in America. The aim of this work was to identify the chemical composition of the essential oil from leaves of Ocotea caudata collected from Colombia. The chemical composition of the oil was determined by gas chromatography-mass spectrometry (GC-MS), being described for the first time. Thirty nine compounds (corresponding to 92.7 percent of the oil) were identified. The major constituents were germacrene D (55.8 percent), bicyclogermacrene (8.0 percent), beta-caryophyllene (4.6 percent) and beta-bourbonene (2.3 percent). Also the antibacterial activity of the oil was evaluated against two Gram (+) and two Gram (-) bacteria showing that the oil exhibited moderated activity against Gram (+) bacteria.

Resumen: Ocotea es un género perteneciente a la familia Lauraceae, que contiene cerca de 56 especies, distribuidas en Asia, Africa yprincipalmente América. El objetivo de este trabajo fue identificar la composición química del aceite esencial de las hojas de Ocoteacaudata colectadas en Colombia. La composición química del aceite fue determinada por cromatografía de gases–espectrometría de masas(GC-MS), siendo descrita por primera vez. Se identificaron treinta y nueve compuestos (correspondientes al 92.7% del aceite). Loscomponentes mayoritarios fueron germacreno D (55.8%), biciclogermacreno (8.0%), β-cariofileno (4.6%) y β-bourboneno (2.3%). Tambiénse evaluó la actividad antibacteriana del aceite frente a dos bacterias Gram (+) y dos Gram (-) encontrándose que el aceite presentómoderada actividad contra las bacterias Gram (+).

Composição química e toxicidade de óleos essenciais para o pulgão-verde Schizaphis graminum (Rondani, 1852) / Chemical composition and toxicity of essential oils to the green-aphid Schizaphis graminum (Rondani, 1852)

Este trabalho teve como objetivo identificar e quantificar os constituintes dos óleos essenciais de Illicum verum, Ageratum conyzoides, Piper hispidinervum e Ocotea odorifera, bem como avaliar a toxicidade para o pulgão-verde Schizaphis graminum. A qualificação dos constituintes foi realizada por meio de um cromatógrafo gasoso + espectrômetro de massas, e a quantificação, por um cromatógrafo gasoso + detector de ionização de chama, ambos com uma coluna DB5. O método de hidrodestilação promoveu um rendimento (p/p) de 3,81% para I. verum, 0,46% para A. conyzoides, 2,85% para P. hispidinervum e 0,68% para O. odorífera. Já os componentes majoritários foram: precoceno (87,0%) e (E)-cariofileno (7,1%) para A. conyzoides; (E)-anetol (90,4%), limoneno (2,6%) e metil-chavicol (1,3%) para I. verum; metil-eugenol (81,2%) e safrol (10,6%) para Ocotea odorífera; e safrol (82,5%) e α-terpinoleno (13,4%) para P. hispidinervum. Pelos testes de toxicidade aguda (24 horas) com folhas de sorgo ou papel-filtro contaminados, verificou-se que o óleo de A. conyzoides foi o mais tóxico para o pulgão, com CL50 de 7,13 e 7,08 µL óleo/cm2 respectivamente, seguido por O. odorifera com CL50 de 11,80 e 103,00 µL óleo/cm2 respectivamente; I. verum de 51,80 µL óleo/cm2 em ambos os substratos; e o menos tóxico foi o óleo essencial de P. hispidinervum, com CL50 de 62,50 e 143,00 µL óleo/cm2, respectivamente. Dessa maneira, sugere-se que o uso dos óleos essenciais pode representar uma nova ferramenta em programas de manejo integrado de pragas.(AU)

The aim of this study was to assess the chemical composition of essential oils of Illicum verum, Ageratum conyzoides, Piper hispidinervum and Ocotea odorífera, as well as their toxicity to the green-aphid Schizaphis graminum. Compound identification was carried out with gas chromatography + mass spectrometry, and quantification with gas chromatography + flame ionization detector, both with DB5 column. The hydrodistillation process promoted oil yield of 3.81% for I. verum; 0.46% for A. conyzoides; 2.85 % for P. hispidinervum; and 0.68 % for O. odorífera. The major components from the oils of A. conyzoides was precocene (87.0%) and (E)-caryophyllene (7.1%); (E)-anethol (90.4%), limonene (2.6%) and methyl-chavicol (1.3%) for I. verum; methyleugenol (81.2%) and safrole (10.6%) for O. odorifera; and safrole (82.5%) and α-terpinolene (13.4%) for P. hispidinervum. The acute toxicity test (24 hours) performed by contact in sorghum leaves or contaminated filter-paper showed that the higher toxicity occur with essential oils of A. conyzoides, with LC50 of 7.01 and 7.01 µg oil/cm2, respectively; followed by O. odorifera, with LC50 of 17.10 and 66.70 µg oil/cm2, respectively; I. verum, with LC50of 66.40 and 65.40 µg oil/cm2, respectively; and low toxicity was observed for the P. hispidinervum essential oil, with LC50 of 64.00 and 143.00 oil/cm2, respectively. With the results obtained in this research, we can state that the use of these essential oils can be a new tool in integrated pest management.(AU)

Anesthetic activity of Brazilian native plants in silver catfish (Rhamdia quelen)

There is an increasing demand for inexpensive and safe anesthetics that can reduce fish stress caused by some procedures such as capture and handling. In this context, the present study evaluated the potential of essential oils (EO) of three Brazilian native plants (Hesperozygis ringens, Lippia sidoides and Ocotea acutifolia) as anesthetics for the silver catfish - Rhamdia quelen. Moreover, an analysis was made of the chemical composition of these oils and their influence on stress parameter. EO of H. ringens and O. acutifolia were effective as anesthetics, without behavioral side effects. EO of O. acutifolia (150 µL L-1) promoted an increase in blood glucose level. Regarding to the composition, pulegone accounts for 96.63% of the EO of H. ringens, and caryophyllene oxide amounts to 56.90% of the EO of O. acutifolia. Two chemotypes, thymol and carvacrol (68.40% and 67.89%, respectively) were verified for EO of L. sidoides. Both samples of EO of L. sidoides showed anesthetic activity in silver catfish, but exposure also caused loss of mucus and mortality. Thus, only the EO of H. ringens and O. acutifolia are advised for anesthetic use.

Existe uma crescente demanda por anestésicos baratos e seguros capazes de reduzir o estresse em peixes produzido durante procedimentos como captura e manuseio. Neste contexto, o presente estudo avaliou o potencial como anestésico dos óleos essenciais (EO) de três espécies vegetais nativas (Hesperozygis ringens, Lippia sidoides e Ocotea acutifolia) em jundiás - Rhamdia quelen. Adicionalmente, a composição química desses óleos e suas influências sobre o estresse também foram avaliadas. Os EO de H. ringens e O. acutifolia foram efetivos como anestésicos sem efeitos adversos detectáveis. EO de O. acutifolia (150 µL L-1) promoveu um aumento na glicemia. Em relação a sua composição, pulegona correspondeu a 96,63% do EO de H. ringens, e óxido de cariofileno a 56,90% do EO de O. acutifolia. Dois quimiotipos, timol e carvacrol (68,40% e 67,89%, respectivamente) foram verificados para os EO de L. sidoides. Ambas as amostras de EO de L. sidoides apresentaram atividade anestésica em jundiás, contudo a exposição produziu perda de muco e mortalidade. Desta forma, somente os EO de H. ringens e O. acutifolia têm seu uso recomendável como anestésicos.

Antiherpetic activity of a flavonoid fraction from Ocotea notata leaves

This study describes the isolation of a flavonoid fraction from leaves of Ocotea notata (Nees & Mart.) Mez, Lauraceae, the identification of six major compounds (an A-type proanthocyanidin trimer [3], isoquercitrin [4], reynoutrin [5], miquelianin [6], quercitrin [7], afzelin [8]) and four minor compounds (catechin [1], epicatechin [2], quercetin [9], kaempferol [10]) present in the fraction and its activity against the Herpes simplex virus type 1 (HSV-1) and type 2 (HSV-2). The 50% effective concentrations values (EC50) calculated from the dose-response curve and the selectivity indices (SI) against the virus were: EC50 35.8 µg/mL and SI 5.5 to HSV-1 and EC50 23.5 µg/mL and SI 8.5 to HSV-2. The flavonoid fraction was more active against HSV-2 than HSV-1. The mechanisms of antiviral action of the flavonoid fraction against the virus were also evaluated. The percentage inhibition (PI) obtained for HSV-2 was higher than 90% in the following assays: virucidal, pre-treatment of cells, treatment of cells after viral adsorption and treatment of cells after viral penetration. For HSV-1, the flavonoid fraction had no effect in pre-treatment of cells and showed 60% of inhibition in virucidal assay.

In vitro anti-inflammatory effects of naturally-occurring compounds from two Lauraceae plants

The in vitro anti-inflammatory effects of seven known lignans and one dihydrochalcone isolated from the leaves of two Lauraceae species (Pleurothyrium cinereum and Ocotea macrophylla), were evaluated through the inhibition of COX-1, COX-2, 5-LOX and the aggregation of rabbit platelets induced by PAF, AA and ADP. (+)-de-4"-O--methylmagnolin 4 was found to be a potent COX-2/5-LOX dual inhibitor and PAF-antagonist (COX-2 IC50 2.27 µM; 5-LOX IC50 5.05 µM; PAF IC50 2.51 µM). However, all compounds exhibited an activity at different levels, indicating good anti-inflammatory properties to be considered in further structural optimization studies.

Os efeitos anti-inflamatórios in vitro de sete conhecidos lignanos e uma dihidrocalcona isolados das folhas de duas espécies da família Lauraceae (Pleurothyrium cinereum e Ocotea macrophylla) foram avaliados por meio da inibição da COX1, COX-2, 5-LOX e agregação de plaquetas de coelhos induzida por PAF, AA e ADP. A (+)-4"-O-metilmagnolina-4 foi encontrada como mais potente inibidora tanto da COX-2 quanto de 5-LOX e antagonista de PAF (COX-2 IC50 2,27 µM; 5- LOX IC50 5,05 µM; PAF IC50 2,51 µM). Entretanto, todos compostos mostram uma atividade em intensidades diferentes, indicando boas propriedades anti-inflamátorias a serem consideradas para futuros estudos de modificações e otimização estruturais.

Atividade antifúngica dos óleos essenciais de sassafrás (Ocotea odorifera Vell. ) e alecrim (Rosmarinus officinalis L. ) sobre o gênero Candida / Antifungal activity of Brazilian sassafras (Ocotea odorifera Vell. ) and rosemary (Rosmarinus officinalis L. ) essential oils against the genus Candida

Este estudo objetivou avaliar, in vitro, a atividade antifúngica dos óleos essenciais de Ocotea odorifera (Vellozo) Rohwer (Sassafrás) e Rosmarinus officinalis L. (Alecrim) sobre cepas de Candida albicans e C. tropicalis, envolvidas com infecções da cavidade oral. Para tanto, 16 cepas de Candida de origem clínica e de referência foram utilizadas para determinação da concentração inibitória mínima (CIM), utilizando a técnica da microdiluição. Miconazol e nistatina foram utilizados como controles positivos. Observou-se discreta atividade antifúngica de ambos os óleos, com CIM de 2,5 mg mL-1 para sassafrás e CIM de 5 mg mL-1 para alecrim em 68 por cento e 81 por cento das cepas avaliadas, respectivamente. Todas as cepas de Candida mostraram-se sensíveis ao miconazol e nistatina. A partir dos resultados obtidos, foi possível concluir que os óleos essenciais de O. odorifera Vell. e R. officinalis L. apresentam fraca atividade sobre cepas de C. albicans e C. tropicalis envolvidas em infecções da cavidade oral.

This study aimed to evaluate the in vitro antifungal activity of essential oils from Ocotea odorifera Vell. (Brazilian sassafras) and Rosmarinus officinalis L. (rosemary) against Candida albicans and C. tropicalis strains, both involved in oral cavity infections. Thus, 16 Candida strains from clinical origin and standards were used to determine the minimum inhibitory concentration (MIC), using the microdilution technique. Miconazole and nystatin were used as positive controls. A slight antifungal activity was observed for both oils, with 2.5 mg mL-1 MIC for Brazilian sassafras and 5 mg mL-1 MIC for rosemary in 68 and 81 percent strains, respectively. All Candida strains were sensitive to miconazole and nystatin. In conclusion, essential oils from O. odorifera Vell. and R. officinalis L. had weak activity against C. albicans and C. tropicalis strains involved in oral cavity infections.