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Revisão Acesso aberto Revisado por pares

Humberto E. Ortega, Daniel Torres‐Mendoza, Luis Cubilla‐Rios,

Plant endophytic fungi spend all or part of their lives inside host tissues without causing disease symptoms. They can colonize the plant to protect against predators, pathogens and abiotic stresses generated by drought, salinity, high concentrations of heavy metals, UV radiation and temperature fluctuations. They can also promote plant growth through the biosynthesis of phytohormones and nutrient acquisition. In recent years, the study of endophytic fungi for biological control of plant diseases ...

Tópico(s): Fungal Biology and Applications

2020 - Multidisciplinary Digital Publishing Institute | Microorganisms

Artigo Acesso aberto Revisado por pares

João Paulo Barreto de Sousa, Madelaine M. Aguilar-Pérez, A. Elizabeth Arnold, Nivia Ríos, Phyllis D. Coley, Thomas A. Kursar, Luis Cubilla‐Rios,

To isolate, characterize and determine the antibacterial activities of compounds produced by the endophytic fungus Diaporthe sp. F2934, cultivated on malt extract agar. The fungus was cultivated aseptically in Petri dishes containing malt extract agar at 25°C for 15 days. Crude extract was obtained from mycelium using ethyl acetate and sonication, and was fractioned using classic chromatography and HPLC. The structures of phomosines and chromanones were established by NMR experiments including HMQC, ...

Tópico(s): Plant Pathogens and Fungal Diseases

2016 - Oxford University Press | Journal of Applied Microbiology

Artigo Revisado por pares

Humberto E. Ortega, Yongchun Shen, Karen TenDyke, Nivia Ríos, Luis Cubilla‐Rios,

A new polyhydroxylated macrolide, named mangiferaelactone (1) was isolated from a solid culture of the endophytic fungus Pestalotiopsis manguiferae, together with ten known compounds [(6S,1′S)-LL-P880α; (6S,1′S,2′R)-LL-P880β; (1′S,2′R)-LL-880γ; (1′R)-dehydropestalotin; (−)-5-carboxylmellein; (−)-5-methylmellein; (−)-5-hydroxylmethylmellein; arabenoic acid; 5,6-dihydro-4-methoxy-2H-pyran-2-one; and the (−)-2-hexylidene-3-methylsuccinic acid]. P. manguiferae was isolated from Hyptis dilatata, a small shrub common in the ...

Tópico(s): Synthetic Organic Chemistry Methods

2014 - Elsevier BV | Tetrahedron Letters

Artigo Revisado por pares

Humberto E. Ortega, Paul R. Graupner, Yumi Asai, Karen TenDyke, Dayong Qiu, Yongchun Shen, Nivia Ríos, A. Elizabeth Arnold, Phyllis D. Coley, Thomas A. Kursar, William H. Gerwick, Luis Cubilla‐Rios,

Two novel reddish-orange alkaloids, mycoleptodiscin A (1) and mycoleptodiscin B (2), were isolated from liquid cultures of the endophytic fungus Mycoleptodiscus sp. that had been isolated from Desmotes incomparabilis in Panama. Elucidation of their structures was accomplished using 1D and 2D NMR spectroscopy in combination with IR spectroscopic and MS data. These compounds are indole-terpenes with a new skeleton uncommon in nature. Mycoleptodiscin B (2) was active in inhibiting the growth of cancer ...

Tópico(s): Plant and fungal interactions

2013 - American Chemical Society | Journal of Natural Products

Artigo Revisado por pares

Teresa Truchuelo, B. Díaz-Ley, Luis Cubilla‐Rios, Javier Alcántara, Pedro Jaén,

Tuberous sclerosis (TS) is the second most common genodermatosis in our country and one of its main characteristics is the presence of facial angiofibromas. These benign tumors can be really bothersome for some patients and there is not a gold-standard treatment. Laser therapy has been used with good responses but it is a painful option and recurrence is guaranteed. TS develops as a result of a mutation of one of two genes, TSC1 or TSC2, which encode for hamartin and tuberin, respectively. TSC1 and ...

Tópico(s): Vascular Tumors and Angiosarcomas

2012 - University of California, Davis | Dermatology Online Journal

Artigo Acesso aberto Revisado por pares

Titto Varughese, Nivia Ríos, Sarah Higginbotham, A. Elizabeth Arnold, Phyllis D. Coley, Thomas A. Kursar, William H. Gerwick, Luis Cubilla‐Rios,

Among thirty four endophytic fungal strains screened for in vitro antagonism, the endophytic fungus Cordyceps dipterigena was found to strongly inhibit mycelial growth of the plant pathogenic fungus Gibberella fujikuroi. Two new depsidone metabolites, cordycepsidone A (1) and cordycepsidone B (2), were isolated from the PDA culture extract of C. dipterigena and identified as being responsible for the antifungal activity. Elucidation of their chemical structures was carried out using 1D and 2D NMR ...

Tópico(s): Entomopathogenic Microorganisms in Pest Control

2012 - Elsevier BV | Tetrahedron Letters

Artigo Acesso aberto Revisado por pares

Sergio Martínez‐Luis, Lilia Chérigo, Elizabeth Arnold, Carmenza Spadafora, William H. Gerwick, Luis Cubilla‐Rios,

With the combined goal of finding the best anti-parasitic and anti-cancer activities as well as isolating the bioactive agents and studying their structures and biological properties, we proceeded to perform a small-scale cultivation of Aspergillus sp. strain F1544 using Potato Dextrose, Malt Extract, Czapek Dox and Eight Vegetables media. From the more promising extracts (obtaining using potato dextrose and czapek dox media in large scale) of this fungus, we isolated the five compounds: pseurotin ...

Tópico(s): Fungal Biology and Applications

2012 - SAGE Publishing | Natural Product Communications

Artigo Acesso aberto Revisado por pares

Eunice Molinar, Nivia Ríos, Carmenza Spadafora, A. Elizabeth Arnold, Phyllis D. Coley, Thomas A. Kursar, William H. Gerwick, Luis Cubilla‐Rios,

Three new terpenoids of mixed biosynthetic origin were isolated from the culture filtrate of the endophytic fungus Pycnoporus sanguineus. Their structures were determined by extensive spectroscopic analyses. We have named these tricyclic and tetracyclic metabolites 'coibanoles A–C' in reference to Coiba Island and Coiba National Park, Panamá, from which the plant and endophyte were collected. The extract was inactive to the human parasites Trypanosoma cruzi, Leishmania donovani, and Plasmodium falciparum ...

Tópico(s): Marine Sponges and Natural Products

2011 - Elsevier BV | Tetrahedron Letters

Artigo Acesso aberto Revisado por pares

Alberto Prado, Julieta Ledezma, Luis Cubilla‐Rios, Jacqueline C. Bede, Donald M. Windsor,

Aulacoscelinae beetles have an ancient relationship with cycads (Cycadophyta: Zamiaceae), which contain highly toxic azoxyglycoside (AZG) compounds. How these "primitive" leaf beetles deal with such host-derived compounds remains largely unknown. Collections were made of adult Aulacoscelis appendiculata from Zamia cf. elegantissima in Panama, A. vogti from Dioon edule in Mexico, and Janbechynea paradoxa from Zamia boliviana in Bolivia. Total AZG levels were quantified in both cycad leaves and adult ...

Tópico(s): Study of Mite Species

2011 - Springer Science+Business Media | Journal of Chemical Ecology

Artigo Acesso aberto Revisado por pares

Eufemio Moreno Pineda, Titto Varughese, Carmenza Spadafora, A. Elizabeth Arnold, Phyllis D. Coley, Thomas A. Kursar, William H. Gerwick, Luis Cubilla‐Rios,

Chemical investigation of a new endophytic fungus, Mycosphaerella sp. nov. strain F2140, associated with the foliage of the plant Psychotria horizontalis (Rubiaceae) in Panama, resulted in the isolation of cercosporin (1) and a new cercosporin analog (3) as the major components. The structures of minor compounds in the extract were elucidated by detailed spectroscopic analysis as 2-(2-butyl)-6-ethyl-3-hydroxy-6-methylcyclohex-2-ene-1,5-dione (4), 3-(2-butyl)-6-ethyl-5-hydroxy-2-methoxy-6-methyl-cyclohex- ...

Tópico(s): Fungal Biology and Applications

2011 - SAGE Publishing | Natural Product Communications

Artigo Acesso aberto Revisado por pares

Ingrid M. Parker, Isis Montalvo Lopez, Jennifer J. Petersen, Natalia Anaya, Luis Cubilla‐Rios, Daniel Potter,

Domestication Syndrome in Caimito (Chrysophyllum cainitoL.): Fruit and Seed Characteristics: The process of domestication is understudied and poorly known for many tropical fruit tree crops. The star apple or caimito tree (Chrysophyllum cainito L., Sapotaceae) is cultivated throughout the New World tropics for its edible fruits. We studied this species in central Panama, where it grows wild in tropical moist forests and is also commonly cultivated in backyard gardens. Using fruits collected over two ...

Tópico(s): Botanical Research and Applications

2010 - Springer Science+Business Media | Economic Botany

Artigo Acesso aberto Revisado por pares

Carlos Jiménez‐Romero, Eduardo Ortega-Barrı́a, A. Elizabeth Arnold, Luis Cubilla‐Rios,

Three lactones were isolated from the culture medium of the endophytic fungus Xylaria sp. Grev. (Xylariaceae). The major compound, which showed weak activity (13 μ g/mL) against a chloroquine-resistant strain of Plasmodium falciparum, was identified as (+)-phomalactone (1). The others were 6-(1-propenyl)-3,4,5,6-tetrahydro-5-hydroxy-4H-pyran-2-one (2) and 5-hydroxymellein (3). Compounds 1 and 2 are reported for the first time as constituents of Xylaria. Also, this is the first report of the activity of the ...

Tópico(s): Plant and fungal interactions

2008 - Taylor & Francis | Pharmaceutical Biology

Artigo Acesso aberto Revisado por pares

Sergio Martínez‐Luis, Gina Della Togna, Phyllis D. Coley, Thomas A. Kursar, William H. Gerwick, Luis Cubilla‐Rios,

Bioassay-directed fractionation of extracts from the fermentation broth and mycelium of the fungus Edenia sp. led to the isolation of five antileishmanial compounds, preussomerin EG1 (1), palmarumycin CP2 (2), palmarumycin CP17 (3), palmarumycin CP18 (4), and CJ-12,371 (5). Compounds 3 and 4 are new natural products, and this is only the second report of compound 1. The structures of compounds 1−5 were established by spectroscopic analyses (HRMS and NMR). All metabolites caused significant inhibition ...

Tópico(s): Microbial Natural Products and Biosynthesis

2008 - American Chemical Society | Journal of Natural Products

Artigo Revisado por pares

Carlos Jiménez‐Romero, Daniel Torres‐Mendoza, Luis David Ureña González, Eduardo Ortega-Barrı́a, Kerry L. McPhail, William H. Gerwick, Luis Cubilla‐Rios,

Two new compounds, 5-(11'(S)-hydroxy-8'-heptadecenyl)resorcinol (3) and 5-(12'(S)-hydroxy-8',14'-heptadecadienyl)resorcinol (4), were isolated from the leaves of Stylogyne turbacensis together with the known analogue metabolites 1 and 2. Compounds 3 and 4 showed the strongest activity in the leishmania assay, 7 and 3 μM, respectively, while compounds 1, 2, and 4 showed moderate activity against a drug-resistant strain of Trypanosoma cruzi with IC50 values of 30, 25, and 22 μM, respectively. Additional ...

Tópico(s): Phytochemical compounds biological activities

2007 - American Chemical Society | Journal of Natural Products

Artigo Acesso aberto Revisado por pares

Eunice Molinar‐Toribio, José González, Eduardo Ortega-Barrı́a, Todd L. Capson, Phyllis D. Coley, Thomas A. Kursar, Kerry L. McPhail, Luis Cubilla‐Rios,

One new prenylated xanthone, 1,5-dihydroxy-3-methoxy-4-isoprenylxanthone (1), along with four previously known prenylated xanthones, ananixanthone (2), 1,3,7-trihydroxy-2,4-diisoprenylaxnthone (3), 8-desoxygartanin (4), and toxyloxanthone A (5), have been isolated from Chrysochlamys tenuis. (Hammel) (Clusiaceae). Compound 1 showed moderate activity (31 ± 9 µM) against a chloroquine-resistant strain of Plasmodium falciparum., and compounds 3 and 5 showed the highest antimalarial potency, IC50 = 20 ± 2 and 16 ± 4 ...

Tópico(s): Traditional and Medicinal Uses of Annonaceae

2006 - Taylor & Francis | Pharmaceutical Biology

Artigo Revisado por pares

Daniel Torres‐Mendoza, José González, Eduardo Ortega-Barrı́a, María V. Heller, Todd L. Capson, Kerry L. McPhail, William H. Gerwick, Luis Cubilla‐Rios,

Three new flavonol arabinosides (2−4) were isolated from the young leaves of Calycolpus warszewiczianus. The structures were determined as myricetin-3-O-α-l-3' '-acetylarabinofuranoside (2), myricetin-3-O-α-l-3' ',5' '-diacetylarabinofuranoside (3), and 5-galloylquercetin-3-O-α-l-arabinofuranoside (4). Molecular structures were elucidated using NMR spectroscopy in combination with IR and MS data. Two known compounds, myricetin-3-O-α-l-arabinofuranoside (1) and (−)-epi-catechin (5), were also isolated. The compounds ...

Tópico(s): Plant biochemistry and biosynthesis

2006 - American Chemical Society | Journal of Natural Products

Artigo Revisado por pares

Jhonny Correa, Carlos Ríos Deidán, Amparo del Rosario Castillo, Luz Romero, Eduardo Ortega-Barrı́a, Phyllis D. Coley, Thomas A. Kursar, María V. Heller, William H. Gerwick, Luis Cubilla‐Rios,

Nine known alkaloids [(+)-isodomesticine (1), (+)-norisodomesticine (2), (+)-nantenine (3), (+)-neolitsine (4), (+)-lirioferine (5), (+)-N-methyllaurotetanine (6), (+)-norlirioferine (7), (+)-isoboldine (8) and (+)-reticuline (9)] were isolated from young leaves of Guatteria dumetorum. Their structures were confirmed by NMR, mass and UV spectral analysis and by comparison to literature data. The growth inhibitory activity of each alkaloid was determined against the parasite Leishmania mexicana. Compounds 1 - 4 all showed significant activity ...

Tópico(s): Plant Parasitism and Resistance

2006 - Thieme Medical Publishers (Germany) | Planta Medica

Artigo Acesso aberto Revisado por pares

Thomas A. Kursar, Catherina Caballero‐George, Todd L. Capson, Luis Cubilla‐Rios, William H. Gerwick, Mahabir P. Gupta, Alicia Ibáñez, Roger G. Linington, Kerry L. McPhail, Eduardo Ortega-Barrı́a, Luz Romero, Pablo N. Solís, Phyllis D. Coley,

Bioprospecting has frequently been cited as a sustainable use of biodiversity. Nevertheless, the level of bioprospecting in biodiversity-rich tropical regions falls below its potential, with the result that bioprospecting has produced only limited economic benefits. We present a bioprospecting program that, in addition to promoting drug discovery, provides economic benefits to and promotes conservation in Panama through the sustainable use of biodiversity. The program was initiated using insights ...

Tópico(s): Biotechnology and Related Fields

2006 - Oxford University Press | BioScience

Artigo Revisado por pares

Lilia Chérigo, Venancio Polanco, Eduardo Ortega-Barrı́a, María V. Heller, Todd L. Capson, Luis Cubilla‐Rios,

Bioactivity-guided fractionation of a MeOH-EtOAc extract from the young leaves of Nectandra lineata (Lauraceae), using a Trypanosoma cruzi bioassay resulted in the isolation of a novel norlignan 3'-methoxy-3,4-methylenedioxy-4',7-epoxy-9-nor-8,5'-neolignan-9'-acetoxy (1), together with the known compound, 3'-methoxy-3,4-methylenedioxy-4'-7-epoxy-9-nor-8,5'-neolignan-7,8'-diene (2). Compounds 1 and 2 were shown to inhibit the growth of T. cruzi epimastigotes in axenic culture.

Tópico(s): Phytochemical compounds biological activities

2005 - Taylor & Francis | Natural Product Research

Artigo Revisado por pares

Daniel Torres‐Mendoza, Luis David Ureña González, Eduardo Ortega-Barrı́a, Phyllis D. Coley, Thomas A. Kursar, Todd L. Capson, Kerry L. McPhail, Luis Cubilla‐Rios,

Four new diterpenes (1−4) were isolated from the leaves of Myrospermum frutescens as minor constituents. Chagresnol (1), 6β,18-diacetoxycassan-13,15-diene (2), and chagreslactone (3) possess cassane skeletons, while chagresnone (4) exhibits a cleistanthane skeleton. Molecular structures and their relative stereochemistries were elucidated using NMR spectroscopy in combination with UV, IR, and MS spectral data. Although compound 2 was previously reported as a synthetic product, we report its first isolation ...

Tópico(s): Plant biochemistry and biosynthesis

2004 - American Chemical Society | Journal of Natural Products

Artigo Acesso aberto Revisado por pares

Yolanda Corbett, Phyllis D. Coley, Luis Cubilla, EDUARDO ORTEGA-BARRIA, Liuris Herrera, Todd L. Capson, José González, Thomas A. Kursar, Luz Romero,

This paper describes the development of a novel microfluorimetric assay to measure the inhibition of Plasmodium falciparum based on the detection of parasitic DNA by intercalation with PicoGreen. The method was used to determine parasite inhibition profiles and 50% inhibitory concentration values of known or potential antimalarial drugs. Values for parasite inhibition with known anti-malarial drugs using the PicoGreen assay were comparable with those determined by the standard method based upon ...

Tópico(s): Computational Drug Discovery Methods

2004 - American Society of Tropical Medicine and Hygiene | American Journal of Tropical Medicine and Hygiene

Artigo Revisado por pares

C. Williams, Omar Ariel Espinosa, Héctor Montenegro, Luis Cubilla, Todd L. Capson, Eduardo Ortega-Barrı́a, Luz Romero,

A colorimetric method for measuring the viability of Leishmania promastigotes is described that is based on the reduction of the tetrazolium salt, XTT, to a water-soluble formazan. Values obtained by the XTT method correlated well with parasite number (r=0.965) and with methods that rely upon the reduction of MTT or MTS (r=0.96 and 0.97, respectively). The IC50 values obtained by XTT method with amphotericin-B, miltefosine and ketoconazole were similar to those previously reported by other methods. ...

Tópico(s): Phytochemistry and biological activities of Ficus species

2003 - Elsevier BV | Journal of Microbiological Methods

Artigo Revisado por pares

Daniel Torres‐Mendoza, Luis David Ureña González, Eduardo Ortega-Barrı́a, Todd L. Capson, Luis Cubilla‐Rios,

Five novel cassane diterpenes (1-5) with activity against Trypanosoma cruzi were isolated from leaves of Myrospermum frutescens. The structures were determined as 18-hydroxycassan-13,15-diene (1), 6beta,18-dihydroxycassan-13,15-diene (2), 6beta-hydroxy-18-acetoxycassan-13,15-diene (3), 18-acetoxy-13,15-diene-19-cassanoic acid (4), and 6beta,13beta-dihydroxy-18-acetoxycassan-14(17),15-diene (5). Structures were elucidated by spectroscopic analysis (NMR and HRCIMS) and by the synthesis of derivatives 2a ...

Tópico(s): Toxin Mechanisms and Immunotoxins

2003 - American Chemical Society | Journal of Natural Products

Carta Revisado por pares

Héctor Montenegro, Marcelino Gutiérrez, Luz Romero, Eduardo Ortega-Barrı́a, Todd L. Capson, Luis Cubilla‐Rios,

Fractionation of Guatteria amplifolia yielded the alkaloids xylopine (1), nornuciferine (4), lysicamine (6), and laudanosine (5). Fractionation of Guatteria dumetorum yielded the alkaloids cryptodorine (2) and nornantenine (3). Compounds 1 - 4 demonstrated significant activity against Leishmania mexicana and L. panamensis. Xylopine (1) was among the most active compounds (LD50 = 3 μM) and showed a 37-fold higher toxicity towards L. mexicana than macrophages, the regular host cells of Leishmania spp.

Tópico(s): Insect Pest Control Strategies

2003 - Thieme Medical Publishers (Germany) | Planta Medica

Revisão Revisado por pares

Phyllis D. Coley, María V. Heller, Rafael Aizprúa, Blanca Araúz, Nayda Flores, Mireya Correa, Mahabir P. Gupta, Pablo N. Solís, Eduardo Ortega-Barrı́a, Luz Romero, Basilio Gómez, Marla Ramos, Luis Cubilla‐Rios, Todd L. Capson, Thomas A. Kursar,

Tropical forests are one of the most diverse and endangered habitats on earth. They have also been portrayed as a source of future pharmaceuticals, yet finding useful compounds can be both scientifically and politically challenging. Increasingly, over the past decade, the potential value of medicinal compounds derived from plants, microorganisms, and animals has been proposed as a tangible benefit of biodiversity, and therefore a basis for promoting its preservation. Ecological theories of plant ...

Tópico(s): Transgenic Plants and Applications

2003 - Wiley | Frontiers in Ecology and the Environment

Artigo Revisado por pares

Julio G. Urones, Isidro S. Marcos, David Dı́ez, Luis Cubilla‐Rios,

Tricyclic diterpenes with the abietane skeleton have been isolated from the aerial parts of Hyptis dilatata. In addition to 12 well known compounds, two new compounds have been isolated and identified as 11,12 diacetoxy-7β-methoxy-8,11,13-abietatrien-20,6β-olide (epimethylrosmanol) and 11,12 diacetoxy-7β-ethoxy-8,11,13-abietatrien-20,6β-olide (epiethylrosmanol). Their structures have been determined by spectroscopic methods using 2D correlation experiments (1H–13C) HMBC and HMQC. Esquirolin B with ...

Tópico(s): Sesquiterpenes and Asteraceae Studies

1998 - Elsevier BV | Phytochemistry

Artigo Revisado por pares

E. Daudén, Pablo Fernández‐Peñas, Luis Cubilla‐Rios, Maribel Jiménez, J Fraga, Jorge Alvar, Amaro García‐Diez,

Three patients are described with leishmaniasis and AIDS, with cutaneous lesions mimicking dermatomyositis. Leishmania organisms were observed in great numbers in the dermis of lesional skin biopsy specimens. They were also present inside keratinocytes in all layers of the epidermis in one patient. Skin cultures from all patients and bone marrow culture in patients 1 and 3 revealed Leishmania infantum. Leishmania organisms were also found in nonlesional skin. The absence of proximal symmetric muscle ...

Tópico(s): Autoimmune Bullous Skin Diseases

1996 - Elsevier BV | Journal of the American Academy of Dermatology

Revisão Acesso aberto Revisado por pares

Humberto E. Ortega, Daniel Torres‐Mendoza, Zuleima Caballero, Luis Cubilla‐Rios,

Among microorganisms, endophytic fungi are the least studied, but they have attracted attention due to their high biological diversity and ability to produce novel and bioactive secondary metabolites to protect their host plant against biotic and abiotic stress. These compounds belong to different structural classes, such as alkaloids, peptides, terpenoids, polyketides, and steroids, which could present significant biological activities that are useful for pharmacological or medical applications. ...

Tópico(s): Plant Pathogens and Fungal Diseases

2021 - Multidisciplinary Digital Publishing Institute | Journal of Fungi

Revisão Acesso aberto Revisado por pares

Daniel Torres‐Mendoza, Humberto E. Ortega, Luis Cubilla‐Rios,

Endophytic fungi are an important group of microorganisms and one of the least studied. They enhance their host’s resistance against abiotic stress, disease, insects, pathogens and mammalian herbivores by producing secondary metabolites with a wide spectrum of biological activity. Therefore, they could be an alternative source of secondary metabolites for applications in medicine, pharmacy and agriculture. In this review, we analyzed patents related to the production of secondary metabolites and ...

Tópico(s): Plant tissue culture and regeneration

2020 - Multidisciplinary Digital Publishing Institute | Journal of Fungi