Bioactive properties of Persea lingue Ness (Lauraceae) fruit and leaf extracts / Propriedades bioativas de extratos de folhas e frutos de Persea lingue Ness (Lauraceae)

Abstract Persea lingue Ness is a tree species that lives mainly in temperate forests of south-central Chile. Its leaves are used in ethnomedicine, the fruit is a drupe similar to that of the avocado and has not been studied. The aim of this study was to determine the cytotoxicity in leukemia cell and antibacterial activity, along with some chemical content characteristics of P. lingue fruit and leaf extracts. The antibacterial activity was determined by the inhibition of bacterial growth in liquid medium assay against Gram-positive and Gram-negative bacteria. The leukemia cell lines Kasumi-1 and Jurkat were used to evaluate the cytotoxic activity by using propidium iodide and AlamarBlue assays. Total phenolic, flavonoid, condensed tannin, alkaloid and lipid contents were evaluated in the fruit and in the leaf extracts. The antioxidant activity of both extracts were also elavaluated. Leaf extract presented the highest content of total phenols, condensed tannins and flavonoids, and also the highest antioxidant activity. While the fruit extract has a higher amount of lipids and alkaloids and the high antibacterial activity against Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, Bacillus megaterium and Micrococcus luteus. The leaf extract only showed activity against M. luteus. Concerning the cytotoxic activity, only the fruit extract showed cytotoxicity against the cell lines Jurkat and Kasumi-1. P. lingue fruit extract is a potential source of biologically active molecules for the development of new drugs to be used in some types of leukemia, as well as antibacterial agent.

Resumo Persea lingue Ness é uma árvore que vive principalmente na floresta temperada do centro-sul do Chile. As folhas são usadas na etnomedicina. O fruto é uma drupa similar ao abacate e que nunca foi pesquisada anteriormente. O objetivo deste estudo foi o de avaliar a citotoxicidade em células leucêmicas e as atividades antibacterianas, assim como algumas características químicas do extrato de fruto e da folha do P. lingue. As atividades antibacterianas foram determinadas pelo método da inibição do crescimento bacteriano em meio líquido empregando-se bactérias Gram-positivas e Gram-negativas. As linhagens celulares leucêmicas, Kasumi-1 e Jurkat foram usadas para avaliar a atividade citotóxica em ensaios empregando-se iodeto de propídio e AlamarBlue. Foram avaliados os teores totais de fenóis, flavonóides, taninos condensados, alcalóides e lipídeos presentes nos extratos das folhas e dos frutos. As atividades antioxidantes de ambos os extratos também foram avaliadas. O extrato das folhas foi o que apresentou o maior conteúdo de fenóis, taninos condensados e flavonóides totais e a maior atividade antioxidante. Já o extrato de fruto apresentou a maior quantidade de lipídios e alcaloides e a melhor atividade antibacteriana contra Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, Bacillus megaterium e Micrococcus luteus. Já o extrato das folhas apresentou apenas atividade contra M. luteus. Em relação à atividade citotóxica, apenas o extrato do fruto apresentou citotoxicidade contra as linhagens celulares Jurkat e Kasumi-1. Em resumo, o extrato do fruto de P. lingue é uma potencial fonte de moléculas com atividade biológica para o desenvolvimento de novos fármacos a serem utilizados em alguns tipos de leucemia, bem como agente antibacteriano.

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

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.

Multivariate statistical analysis of the essential oils of five Beilschmiedia species from Peninsular Malaysia / Análisis estadístico multivariado de los aceites esenciales de especies de Beilschmiedia de Malasia peninsular

Identification of the chemical compositionof essential oils is very important for ensuring the quality of finished herbal products. The objective of the study was to analyze the chemical components present in the essential oils of five Beilschmiediaspecies (i.e. B. kunstleri, B. maingayi, B. penangiana, B. madang, and B. glabra) by multivariate data analysis using principal component analysis (PCA) and hierarchical clustering analysis (HCA) methods. The essential oils were obtained by hydrodistillation and fully characterized by gas chromatography (GC) and gas chromatography-mass spectrometry (GC-MS). A total of 108 chemical components were successfully identified from the essential oils of five Beilschmiediaspecies. The essential oils were characterized by high proportions of ß-caryophyllene (B.kunstleri), δ-cadinene (B. penangianaand B. madang), and ß-eudesmol (B. maingayiand B. glabra). Principal component analysis (PCA) and hierarchical cluster analysis (HCA) revealed that chemical similarity was highest for all samples, except for B. madang. The multivariate data analysis may be used for the identification and characterization of essential oils from different Beilschmiediaspecies that are to be used as raw materials of traditional herbal products.

La identificación de la composición química de los aceites esenciales es muy importante para garantizar la calidad de los productos herbales terminados. El objetivo del estudio fue analizar los componentes químicos presentes en los aceites esenciales de cinco especies de Beilschmiedia (B. kunstleri, B. maingayi, B. penangiana, B. madangy B. glabra) mediante análisis de datos multivariados utilizando los métodos de análisis de componente principal (PCA) y análisis de agrupamiento jerárquico (HCA). Los aceites esenciales se obtuvieron por hidrodestilación y se caracterizaron completamente por cromatografía de gases (GC) y cromatografía de gases-espectrometría de masas (GC-MS). Se identificaron con éxito un total de 108 componentes químicos a partir de los aceites esenciales de las cinco especies de Beilschmiedia. Los aceites esenciales se caracterizaron por altas proporciones de ß-cariofileno (B. kunstleri), δ-cadineno (B. penangianay B. madang) y ß-eudesmol (B. maingayiy B. glabra). El análisis de componentes principales (PCA) y el análisis de conglomerados jerárquicos (HCA) revelaron que la similitud química fue más alta para todas las muestras, excepto para B. madang. El análisis de datos multivariados puede usarse para la identificación y caracterización de aceites esenciales de diferentes especies de Beilschmiedia que se utilizan como materias primas de productos herbales tradicionales.

Actividad repelente del aceite esencial de Laurelia sempervirens (Ruiz & Pav.) Tul. (Monimiaceae) en Triatoma infestans (Klug)(Reduviidae) / Repellent activity of the essential oil from Laurelia sempervirens (Ruiz & Pav.) Tul. (Monimiaceae) on Triatoma infestans (Klug) (Reduviidae)

Triatoma infestans (Klug) es el vector principal de la enfermedad de Chagas en Bolivia y los países vecinos. El objetivo de este estudio fue determinar la composición química del AE del laurel chileno, Laurelia sempervirens (Ruiz & Pav.) Tul. (Monimiaceae) y evaluar su efecto repelente en ninfas del quinto estadio de T. infestans. La AE de L. sempervirens se obtuvo por hidrodestilación y se analizó por cromatografía de gases acoplada a espectrometría de masas (CG-EM). Sus componentes principales fueron cis-isosafrol (89.8%), ß-terpineno (3.9%), trans-ocimeno (2.7%) y metileugenol (2.2%). La repelencia se evaluó en un círculo de papel de filtro dividido en dos zonas iguales que se impregnaron con sustancias de prueba [AE o N,N-dietil-3-metilbenzamida (DEET) como control positivo] y acetona como control en blanco, respectivamente. Se analizaron varias concentraciones de sustancias de prueba entre 4.125 y 132 µg/cm2. El AE de L. sempervirens produjo una repelencia significativa a concentraciones iguales o superiores a 66.0 µg/cm2, mientras que DEET repelió a partir de 16.5 µg/cm2. Futuros trabajos serán orientados al estudio de las propiedades repelentes de cis-isosafrol solo y mezclado con ß-terpineno, trans-ocimeno y metileugenol en T. infestans.

Triatoma infestans (Klug) is the principal vector of Chagas disease in Bolivia and neighboring countries. The objective of this study was to determine the chemical composition of the EO of the Chilean laurel, Laurelia sempervirens (Ruiz & Pav.) Tul. (Monimiaceae) and to evaluate its repellent effect on fifth-instar nymphs of T. infestans. The EO from L. sempervirens was obtained by hydrodistillation and analyzed by gas chromatography coupled to mass spectrometry (GC-MS). Their main components were cis-isosafrole (89.8%), ß-terpinene (3.9%), trans-ocimene (2.7%) and methyleugenol (2.2%). Repellency was evaluated on a circle of filter paper divided into two equal zones which were impregnated with test substances [EO or N,N-diethyl-3-methylbenzamide (DEET) as positive control] and acetone as blank control, respectively. Several concentrations of test substances between 4.125 and 132 µg/cm2 were tested. The EO from L. sempervirens produced significant repellency at concentrations equal or above 66.0 µg/cm2, while DEET repelled starting at 16.5 µg/cm2. Future works will be oriented to the study of repellent properties of cis-isosafrole alone and mixed with ß-terpinene, trans-ocimene and methyleugenol on T. infestans.

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.

Lindera aggregata (Sims) Kosterm: review on phytochemistry and biological activities / Lindera agreggata (Sims) Kosterm: revisión de su fitoquímica y actividades biológicas

The genus Lindera consists of approximately 100 species that are widely distributed in tropical and subtropical areas throughout the world. Most Lindera plants, particularly Lindera aggregata is a well-known traditional Chinese medicine that has important medicinal value and health benefits. Contemporary chemical and pharmacological studies have shown that L. aggregata are a source of structurally diverse molecules having pharmacological potential. In an effort to promote research on L. aggregata and develop therapeutic and pharmacological products, this review describes the structural diversity of its components and pharmacological and biological significance of L. aggregata. This review is based on a literature analysis of scientific journals from electronic sources, such as Science Direct, PubMed, Google Scholar, Scopus and Web of Science. Thus, with the growing interest in traditional medicine and botanical drugs worldwide, L. aggregata will increasingly capture chemists' and pharmacologists' attention because they produce diverse and structurally novel compounds having pharmacological significance.

El género Lindera consta de aproximadamente 100 especies que están ampliamente distribuidas en áreas tropicales y subtropicales en todo el mundo. La mayoría de las plantas de Lindera, particularmente Lindera aggregata, es parte conocida de la medicina tradicional china con un importante valor medicinal y beneficios para la salud. Estudios químicos y farmacológicos contemporáneos han demostrado que L. aggregata es una fuente de moléculas estructuralmente diversas que con potencial farmacológico. En un esfuerzo por promover la investigación sobre L. aggregata y desarrollar productos terapéuticos y farmacológicos, esta revisión describe la diversidad estructural de sus componentes y la importancia farmacológica y biológica de L. aggregata. Esta revisión se basa en un análisis de literatura de revistas científicas de fuentes electrónicas, como Science Direct, PubMed, Google Scholar, Scopus y Web of Science. Por lo tanto, con el creciente interés en la medicina tradicional y las drogas botánicas en todo el mundo, L. aggregata captará cada vez más la atención de los químicos y farmacólogos debido a que producen compuestos diversos y estructuralmente novedosos que tienen importancia farmacológica.

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.

Antileishmanial activity and immunomodulatory effect of secosubamolide, a butanolide isolated from Nectandra oppositifolia (Lauraceae)

Visceral leishmaniasis is a complex neglected tropical disease caused by Leishmania donovani complex. Its current treatment reveals strong limitations, especially high toxicity. In this context, natural products are important sources of new drug alternatives for VL therapy. Therefore, the antileishmanial and immunomodulatory activity of compounds isolated from Nectandra oppositifolia (Lauraceae) was investigated herein. Methods: The n-hexane extract from twigs of N. oppositifolia were subjected to HPLC/HRESIMS and bioactivity-guided fractionation to afford compounds 1 and 2 which were evaluated in vitro against Leishmania (L.) infantum chagasi and NCTC cells. Results: The n-hexane extract displayed activity against L. (L.) infantum chagasi and afforded isolinderanolide E (1) and secosubamolide A (2), which were effective against L. (L.) infantum chagasi promastigotes, with IC50 values of 57.9 and 24.9 µM, respectively. Compound 2 was effective against amastigotes (IC50 = 10.5 µM) and displayed moderate mammalian cytotoxicity (CC50 = 42 µM). The immunomodulatory studies of compound 2 suggested an anti-inflammatory activity, with suppression of IL-6, IL-10, TNF with lack of nitric oxide. Conclusion: This study showed the antileishmanial activity of compounds 1 and 2 isolated from N. oppositifolia. Furthermore, compound 2 demonstrated an antileishmanial activity towards amastigotes associated to an immunomodulatory effect.(AU)

Chemical Constituents of Bark of Beilschmiedia kunstleri Gamble with Anticancer, Anti-Streptococcus pyogenes, Anti-Bacillus cereus and Anti Plesiomonas shigelloides Activities

Lauraceae is a family medicinal plant whose tubers possesses antimicrobial, and cytotoxic, such as antiparasitic and anti-inflammatory special effects and has been used for the medicine in the cure of hepatitis and rheumatism. The antimicrobial activities of bioactive compounds including one neolignan; kunstlerone (1) and two alkaloids include isocaryachine (2) and noratherosperminine (3) as well as crude hexane, methanol and dichloromethane extracts were evaluated. Additionally, the effect of compounds 1, 2 and 3 were evaluated on A549, PC-3, A375, HT-29 and WRL-68 cell lines. In conclusion, kunstlerone 1 showed moderate cytotoxicity against various cancer cell lines such as A549, PC-3, A375, HT-29 and WRL-68, respectively with EC₅₀ values of 28.02, 26.78, 33.78, 33.65 and 16.46 µg/mL. The crude methanol extract showed antigrowth activity against S. pyogenes II and B. cereus, with MICs of 256 µg/mL. The compounds kunstlerone (1), isocaryachine (2) and noratherosperminine (3) showed complete inhibition against P. shigelloides, with MIC ≤60 µg/mL compare to ampicillin, as a positive control, which showed antigrowth activity against P. shigelloides at MIC 10 µg/mL.

Cytotoxic Lactones from the Pericarps of Litsea japonica

From the pericarps of Litsea japonica (Thunb.) Jussieu, eighteen butanolide derivatives (1 – 18) were evaluated for their cytotoxic activity against HeLa, HL-60, and MCF-7 cells. Compounds 1 – 9 with 2-alkylidene-3-hydroxy-4-methylbutanolides structure exhibited cytotoxic activities against cancer-cell lines. Among them, compound 8 (litsenolide D₂) exhibited the most potent cytotoxicity against the tested cell lines, including HeLa, HL-60, and MCF-7, with IC₅₀ values of 17.6 ± 1.3, 4.2 ± 0.2, and 12.8 ± 0.0 µM, respectively. Compound 8 induced apoptosis in a dose-dependent manner. Annexin V/Propidium Iodide (PI) double staining confirmed that 8 effectively induced apoptosis in MCF-7 cells. To the best of our knowledge, we have reported cytotoxic activity of butanolides from L. japonica against these cancer-cell lines for the first time.

Estudos farmacológicos de novos compostos semissintéticos com potencial terapêutico na doença de chagas / Pharmacological studies of new semi-synthetic compounds with therapeutic potential in Chagas disease

A doença de Chagas afeta mais de 8 milhões de pessoas nos países em desenvolvimento, e dispõe de uma terapia ultrapassada e altamente tóxica. Considerando o Brasil uma das maiores biodiversidades do mundo, compostos de sua flora podem contribuir como novos protótipos farmacêuticos. Neolignanas, isoladas da planta Nectandra leucantha, apresentaram previamente atividade anti-Trypanosoma cruzi e neste trabalho, serviram como base para a semissíntese de uma série de 24 análogos. Estudos in vitro demonstratram que 19 compostos não apresentaram citotoxicidade em células de mamífero até 200 µM. Seis compostos apresentaram atividade contra as formas tripomastigotas (CE50 8 a 76 µM) e 8 compostos contra os amastigotas intracelulares (CE50 7 a 16 µM). Estudos da relação estrutura-atividade biológica (SAR), demonstraram que a presença de pelo menos uma cadeia lateral alílica era importante para a atividade anti-T. cruzi e que o grupo fenol não era essencial. O composto 8 foi eficaz contra as duas formas do parasita e eliminou 100% das formas amastigotas no interior dos macrófagos, sendo escolhido para estudos de mecanismo de ação. O composto 8 afetou rapidamente a mitocôndria do T. cruzi,...(AU)

Chagas disease affects more than 8 million people in developing countries and the available therapy is old and highly toxic. Considering Brazil one of the biggest biodiversity in the world, compounds from the flora can contribute as new pharmaceutical prototypes. Neolignans, isolated from the plant Nectandra leucantha, previously showed anti-Trypanosoma cruzi activity and served as the basis for the semi-synthesis of a series of 24 analogues. In vitro studies demonstrated that 19 compounds caused no cytotoxicity in mammalian cells up to 200 µM. Six compounds showed activity against trypomastigote forms (IC50 8 to 76 µM) and 8 compounds against intracellular amastigotes (IC50 7 to 16 µM). Studies of the structure activity relationships (SAR) showed that the presence of at least one allylic side chain was important for anti-T. cruzi activity and that the phenol group was not essential. Compound 8 was chosen for mechanism of action studies as it was effective against both forms of the parasite and eliminated 100% of the intracellular amastigotes. Compound 8 rapidly affected the mitochondria of T. cruzi, causing an intense depolarization of the mitochondrial membrane potential, with decreasing levels of reactive oxygen species...(AU)

Neolignanas semissintéticas como novos candidatos anti-leishmania: estudo do mecanismo ação / Semissintéticas as new candidates oncometopia facialis anti-leishmania: study of action mechanism

Doenças tropicais negligenciadas, como a leishmaniose visceral (LV), afetam populações de baixa renda e apresentam um desafio para a saúde pública. A quimioterapia disponível para LV apresenta diversas limitações, como elevada toxicidade e custo, além de dificuldades de administração. Na busca por alternativas terapêuticas, o estudo de produtos naturais representa uma forma promissora na introdução de novos medicamentos para essa doença. No presente trabalho, foi realizada uma triagem in vitro em Leishmania (L.) infantum de 25 novos compostos semissintéticos derivados da neolignana desidrodieugenol B, isolada da planta Nectandra leucantha (Lauraceae). Dentre eles, quatro (FS017, FS034, FS008 e FS022) demonstraram atividade em amastigotas intracelulares e promastigotas, com...

Neolignans isolated from twigs of Nectandra leucantha Ness & Mart (Lauraceae) displayed in vitro antileishmanial activity

The therapeutic arsenal for the treatment of Leishmaniasis is limited and includes toxic compounds (antimonials, amphotericin B, pentamidine and miltefosine). Given these aspects, the search for new compounds based on floristic biodiversity is crucial. In the present work, we report the isolation, characterization and antileishmanial activity of six related neolignans (1­6) of bioactive extract from Nectandra leucantha (Lauraceae) twigs. Methods: Dried and powdered twigs of N. leucantha were exhaustively extracted using n-hexane. The crude extract was dereplicated by HPLC/HRESIMS and subjected to column chromatography to yield pure compounds 1­6. Their chemical structures were identified via NMR and comparison of obtained data with those previously published in the literature. Biological assays of compounds 1­6 and their respective monomers (eugenol and methyleugenol) were performed using promastigote and amastigote forms of Leishmania (L.) infantum. Results: Dereplication procedures followed by chemical characterization of isolated compounds by NMR enabled the identification of related neolignans 1­6. Neolignans 2, 4 and 6 showed potential against amastigote forms of L. (L.) infantum (EC50 values of 57.9, 67.7 and 13.7 µM, respectively), while compounds 1 and 3 were inactive. As neolignans 2­4 are chemically related, it may be suggested that the presence of the methoxyl group at C4 constitutes an important structural aspect to increase antileishmanial potential against amastigote forms. Compound 6, which consists of a methylated derivative of compound 5 (inactive) showed antileishmanial activity similar to that of the standard drug miltefosine (EC50 =16.9 µM) but with reduced toxicity (SI = 14.6 and 7.2, respectively). Finally, two related monomers, eugenol and methyleugenol, were also tested and did not display activity, suggesting that the formation of dimeric compounds by oxidative coupling is crucial for antiparasitic activity of dimeric compounds 2, 4 and 6. Conclusion: This study highlights compound 6 against L. (L.) infantum amastigotes as a scaffold for future design of new compounds for drug treatment of visceral leishmaniasis.(AU)

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

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 (+).

In vitro antioxidant, antitumor and leishmanicidal activity of riparin A, an analog of the Amazon alkamides from Aniba riparia (Lauraceae) / Atividade antioxidante, antitumoral e leishmanicida in vitro da riparina A, um análogo das alcamidas amazônicas de Aniba riparia (Lauraceae)

Aniba riparia (Lauraceae) is an important medicinal plant found in the Amazon region and presents alkaloids of the type alkamide known as riparins. Riparin A is structurally represented as the fundamental core of all Amazon riparins. This work aimed to assess the in vitro antioxidant, antitumor and antileishmanial effects of riparin A. Riparin A presented weak antioxidant capacity by tecniques of DPPH• (EC50 of 296.2 μg mL-1) and ABTS•+ (EC50 of 450.1 μg mL-1), showed moderate activity against colon carcinoma (HCT-116: IC50 of 21.7 μg mL-1) and leishmanicidal activity on promastigotes of L. amazonensis (IC50 of 307.0 ± 79.6, 193.7 ± 44.3 and 81.8 ± 11.2 μg mL-1, respectively, after 24, 48 and 72 h of incubation). Then, in addition to its structural simplicity, riparin A revealed promising biological activities and remarkable in vitro leishmanicidal action, an important result in epidemiological point of view to control leishmaniasis in Brazil, including in the Amazon region.

Aniba riparia (Lauraceae) é uma importante planta medicinal encontrada na região amazônica que apresenta alcaloides do tipo alcamida e conhecidos como riparinas. Este trabalho teve como objetivo avaliar os efeitos antioxidantes, antitumorais e leishmanicidas in vitro da riparina A. Riparina A apresentou fraca capacidade antioxidante pelas técnicas do DPPH• (CE50 de 296,2 μg mL-1) e ABTS•+ (CE50 de 450,1 μg mL-1), mostrou moderada atividade contra carcinoma de cólon (HCT-116: CI50 de 21,7 μg mL-1) e atividade leishmanicida sobre formas promastigotas de Leishmania amazonensis (CI50 de 307,0 ± 79,6; 193,7 ± 44,3 e 81,8 ± 11,2 μg mL-1, respectivamente, após 24, 48 e 72 h de incubação). Assim, além de sua simplicidade estrutural, a riparina A revelou atividades biológicas promissoras e significativa ação leishmanicida in vitro, resultado importante diante da relevância epidemiológica para controle da leishmaniose no Brasil, inclusive na região amazônica.

Effect of (+)-dehydrofukinone on GABAA receptors and stress response in fish model

(+)-Dehydrofukinone (DHF) is a major component of the essential oil of Nectandra grandiflora (Lauraceae), and exerts a depressant effect on the central nervous system of fish. However, the neuronal mechanism underlying DHF action remains unknown. This study aimed to investigate the action of DHF on GABAA receptors using a silver catfish (Rhamdia quelen) model. Additionally, we investigated the effect of DHF exposure on stress-induced cortisol modulation. Chemical identification was performed using gas chromatography-mass spectrometry and purity was evaluated using gas chromatography with a flame ionization detector. To an aquarium, we applied between 2.5 and 50 mg/L DHF diluted in ethanol, in combination with 42.7 mg/L diazepam. DHF within the range of 10-20 mg/L acted collaboratively in combination with diazepam, but the sedative action of DHF was reversed by 3 mg/L flumazenil. Additionally, fish exposed for 24 h to 2.5-20 mg/L DHF showed no side effects and there was sustained sedation during the first 12 h of drug exposure with 10-20 mg/L DHF. DHF pretreatment did not increase plasma cortisol levels in fish subjected to a stress protocol. Moreover, the stress-induced cortisol peak was absent following pretreatment with 20 mg/L DHF. DHF proved to be a relatively safe sedative or anesthetic, which interacts with GABAergic and cortisol pathways in fish.

Assesment of platelet antiaggregant activity of a fraction from an ethanolic extract of the bark of Nectandra amazonum Nees / Evaluación de la actividad antiagregante plaquetaria de una fracción del extracto etanólico de corteza de Nectandra amazonum Nees

Background: Some species of the Lauraceae family are known to produce secondary metabolites that have antiplatelet properties. Studies on the leaves of Nectandra amazonum Nees. have shown antiaggregant activity but the bark of this species has not been studied. Objectives: To assess the antiplatelet effect of the ethanolic fraction obtained from the bark of Nectandra amazonum Nees. [N.V. "laurel amarillo", Lauraceae] applying the "Born" turbidimetric method. Methods: The screening test compared the effects of a fraction of N. amazonum (0.1 mg/mL), acetylsalicylic acid (ASA, 0.5 mM, as reference standard) and dimethylsulphoxide (DMSO, 0.1%, as control) on human platelets stimulated with adenosine diphosphate (ADP, 2 µM), epinephrine (EPI, 1 uM (one micromolar)), collagen (COLL, 1 µg/mL) and arachidonic acid (AA, 0.2 mg/mL). Subsequently, the study focused on determining the antiaggregant potency of the N. amazonum fraction through concentration - response curves (from 1 µg/mL to 0.4 mg/ mL), obtaining pIC50 (-log IC50) values against the platelet agonists. Results: Control platelets attained the highest percentage values of aggregation (96% AA, 89% EPI, 85% COLL, and 77% ADP). The N. amazonum fraction significantly reduced the aggregation effects (6% AA, 45% EPI, 10% COLL, 21% ADP), with values close to those obtained with ASA (17% AA, 21% EPI, 10% COLL, 20% ADP). According to concentration - response curves, the pIC50 values of the ethanolic fraction indicated the following order of potency: AA, 4.90 > ADP, 4.51 > COLL, 4.33 > EPI, 3.85. Conclusions: These results suggest that the N. amazonum Nees. ethanolic fraction elicited antiplatelet effects mainly related to the inhibition of the arachidonic acid pathway.

Antecedentes: Algunas especies de la familia Lauraceae poseen metabolitos secundarios que ejercen efectos antiplaquetarios. Estudios de las hojas de Nectandra amazonum Nees. han mostrado esa actividad, pero no se conoce sobre las propiedades antiagregantes de su corteza. Objetivos: Evaluar el efecto antiagregante plaquetario de la fracción etanólica obtenida de la corteza de Nectandra amazonum Nees. [N.V. "laurel amarillo", Lauraceae] aplicando el método turbidimétrico de Born. Métodos: En el tamizaje antiagregante se comparó la fracción de N. amazonum (0,1 mg/mL) con ácido acetil salicílico (ASA 0,5 mM, como estándar de referencia) y dimetilsulfóxido (DMSO, 0,1%, como control) en plaquetas humanas estimuladas con adenosin difosfato (ADP, 2 µM), epinefrina (EPI, 1 uM (uno micromolar)), colágeno (COLL, 1 µg/mL) y ácido araquidónico (AA, 0,2 mg/mL). Posteriormente, el estudio se enfocó en la determinación de la potencia antiagregante de la fracción mediante curvas de concentración - respuesta (desde 1 µg/mL hasta 0,4 mg/mL) para obtener los valores respectivos de pIC50 (-log CI50). Resultados: En el grupo control se alcanzaron altos valores de agregación plaquetaria (96% AA, 89% EPI, 85% COLL, 77% ADP). La fracción de N. amazonum redujo significativamente la agregación (6% AA, 45% EPI, 10% COLL, 21% ADP), con valores próximos a los obtenidos con ASA (17% AA, 21% EPI, 10% COLL, 20% ADP). De acuerdo con las curvas de concentración ­ respuesta, los valores de pIC50 arrojaron el siguiente orden de potencia: AA, 4,90 > ADP, 4,51 > COLL, 4,33 > EPI, 3,85. Conclusiones: Estos resultados sugieren que la fracción etanólica de N. amazonum Nees ejerce efectos antiplaquetarios relacionados especialmente con la cascada metabólica del ácido araquidónico.

Genus Nectandra: phytochemistry and biological activity / Género Nectandra: fitoquímica y actividad biológica

The genus Nectandra belongs to the Ocotea complex and these species (Nectandra) are generally trees. It is considered endemic in the Neotropics. This genus has been reported uses in folk medicine as antifungal, anti-inflammatory, antimalarial, analgesic, treatment of ulcers, and febrifuge, among others; have also been reported some biological activity assays including: antitumor and antimalarial activity, activity against cardiovascular disease, among others. The genus Nectandra contains different secondary metabolites and they have been reported: Alkaloids; such as aporfinic, proaporfin, benzylisoquinoline, bisbenzylisoquinoline, and morfinandienone-type; lignans and neolignans, furofuran, benzofuran, tetrahydrofuran and dihydrofuran, and 3,3-neolignans-type; terpenes and sesquiterpenoid (monocyclic and bicyclic); Phytosterols and derived from those (3-hydroxy and the 3-ketone pentacyclic compounds); flavonoids, particularly O- glycosylated; xanthones, phenolic acids, polyalcohol, and alkene-alkyne, especially rubrenolide and rubrynolide.

El género Nectandra pertenece al complejo Ocotea y estas especies (Nectandra) son por lo general árboles. Se considera endémica en el Neotrópico. Este género se ha informado de usos en medicina popular como antifúngico, anti-inflamatorio, antimalárico, analgésico, el tratamiento de las úlceras, y febrífugo, entre otros; También se han informado de algunos ensayos de actividad biológica, incluyendo: antitumoral y actividad antipalúdica, actividad contra las enfermedades cardiovasculares, entre otros. El género Nectandra contiene diferentes metabolitos secundarios y se han reportado alcaloides; tales como aporfinas, proaporfina, benzylisoquinolina, y del tipo morfinandienona; lignanos y neolignanos, furofuran, benzofurano, tetrahidrofurano y dihidrofurano, y del tipo 3,3-neolignanos; terpenos y sesquiterpenoide (monocíclicos y bicíclicos); Los fitoesteroles se derivan de aquellos (3-hidroxi y los compuestos pentacíclicos 3-cetona); flavonoides, particularmente O-glicosilada; xantonas, ácidos fenólicos, polialcohol, y alqueno-alquino, especialmente rubrenolide y rubrynolida.