Artículos científicos

URI permanente para esta colecciónhttp://10.0.96.45:4000/handle/11056/14837

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Does the persistence of sweet chestnut depend on cultural inputs? Regeneration, recruitment, and mortality in Quercusand Castanea-dominated forests
(Springer Nature, 2018) Silla Cortés, Fernando; Camisón, Álvaro; Solana, Andrea; Hernández, Héctor; Ríos, Guillermo; Cabrera, Miguel; López, Dámaris; Morera Beita, Albert
Los bosques secundarios de Quercus muestran una transición gradual hacia bosques mixtos, siendo cada vez más abundante el castaño (Castanea sativa) en el Sistema Central occidental español. Además, en masas dominadas por el castaño, muestra cierta resistencia al desplazamiento competitivo de Quercus pyrenaica. Nuestros resultados refutan parcialmente la opinión tradicional de que C. sativa no puede reclutar en ausencia de aportes culturales. Contexto: El castaño, Castanea sativa, es un componente de los bosques latifoliados europeos y es uno de los árboles mejor gestionados. Debido a una reducción de los insumos culturales, los rodales dominados por el castaño tienden a ser invadidos por otras especies, y no está claro cómo el castaño puede persistir en los bosques mixtos naturales. Objetivos: Nuestro trabajo tuvo como objetivo identificar los principales factores que limitan el establecimiento de C. sativa y analizar los procesos de reclutamiento y mortalidad de árboles de C. sativa. Métodos: Se analizó la edad, los patrones de anillos de crecimiento, la densidad de regeneración y la estructura espacial de árboles y plantones en 11 parcelas del Sistema Central Español. Resultados:La densidad de plántulas de castaño aumentó con el área basal de C. sativa, pero la transición hacia la etapa de retoño pareció limitada debido a la disponibilidad de luz. En los bosques secundarios de Quercus pyrenaica, las escasas copas de los árboles no limitaron la regeneración del castaño, y en los rodales viejos de castaño, C. sativa mostró cierta resistencia al desplazamiento competitivo. Por el contrario, los montes jóvenes mixtos mostraron una alta mortalidad, probablemente debido a la competencia con otros rebrotadores vigorosos.
La red internacional de inventarios forestales (BIOTREE-NET) en Mesoamérica: avances, retos y perspectivas futuras
(Asociación Española de Ecología Terrestre, 2012) Cayuela, Luis; Gálvez Bravo, L.; de Albuquerque, F.S.; Golicher, D. J.; González Espinosa, M.; Ramírez Marcial, N.; Rey Benayas, José María; Zahawi, R.A.; Meave, J.A.; Benito, B.M.; Garibaldi, C.; Chan, I.; Pérez Pérez, R.; Field, R.; Balvanera, P.; Castillo, M.A.; Figueroa Rangel, B.L.; Griffith, D.M.; Islebe, G.A.; Kelly, D.L.; Olvera Vargas, M.M; Schnitzer, S.A.; Velazquez, E.; Williams Linera, G.; Brewer, S.W.; Camacho Cruz, A.; Coronado, I.; de Jong, B.; del Castillo, R.R.; Granzow de la Cerda, I.; Fernández, J.; Fonseca González, William; Galindo Jaimes, L.; Gillespie, T.W.; González Rivas, B.; Gordon, J.E; Hurtado, J.; Linares, J.; Letcher, S.G.; Mangan, S.A; Méndez, V.E.; Meza, V.; Ochoa-Gaona, S.; Peterson, C.J.; Ruiz Gutierrez, V.; Snarr, K.A.; Tun Dzul, F.; Valdez Hernández, M.; Viergever, K.M.; White, D.A.; Williams, J.N.; Bonet, F.J.; Zamora, R.
Los esfuerzos de conservación en la región neotropical están limitados por la falta de información disponible sobre las especies, ya que muchas no han sido descritas o se tiene poca información sobre ellas. La Red Internacional de Inventarios Forestales (BIOTREE-NET) concentra y facilita el acceso a la información y el intercambio entre investigadores, gestores y conservacionistas, organizando y estandarizando los datos de especies de árboles procedentes de inventarios forestales en la región mesoamericana en una única base de datos que incluya información espacial. Este artículo explica el ámbito y objetivos de la red, describe la estructura de la base de datos e identifica los principales avances realizados, así como los retos y perspectivas futuras. La base de datos contiene más de 50 000 registros de árboles de unas 5000 especies, distribuidas en más de 2000 parcelas muestreadas desde el suroeste de México hasta Panamá. La información es heterogénea, tanto en su naturaleza y forma como en la cobertura geográfica de los inventarios. La base de datos tiene una estructura relacional, con 12 tablas interconectadas, incluyendo información sobre las parcelas, los nombres de las especies, el diámetro a la altura del pecho de los árboles medidos y sus atributos funcionales. Se ha desarrollado un sistema para la corrección de errores tipográficos y la estandarización taxonómica y nomenclatural utilizando como referencia The Plant List (http://theplantlist.org/). También se han generado modelos de distribución potencial para cerca de 1700 especies utilizando distintos métodos y en el futuro se prevé habilitar también el acceso público a los modelos de distribución de especies a través del portal web (http://portal.biotreenet.com). Aunque BIOTREE-NET ha contribuido al desarrollo de mejores modelos de distribución, su mayor potencial radica, en nuestra opinión, en el estudio a nivel de comunidades. Finalmente, se reconoce la necesidad de expandir la red a través de la participación de más investigadores interesados en colaborar con datos para ampliar el conocimiento sobre la biodiversidad forestal en la región neotropical.
Altitudinal zonation of montane Quercus forests along two transects in Chirripó National Park, Costa Rica
(Springer, 1995-08) Kappelle, Maarten; Van Uffelen, Jan-Gerrit; Cleef, Antoine
Abiotic and vegetation data were collected along two altitudinal transects through mature montane Quercus forests on the Pacific and Atlantic slopes of Costa Rica's Chirripó Massif. Between 2000 and 3200 m asl twenty-four 0.05 ha forest plots were selected at altitudinal intervals of 100 m, and eight soil profiles were described at intervals of 200 m. A TWINSPAN classification aided in the determination of eight zonal forest communities on the basis of their floristic composition. They are grouped in two sets of four: (i) the palm-rich lauraceous-fagaceous Lower Montane Mollinedia-Quercus Forests (2000-2600 m asl) and (ii) the bamboo-rich myrsinaceous-fagaceous Upper Montane Schefflera-Quercus Forests (2500-3200 m asl), respectively. Vegetation changes seem correlated with two major climatic gradients: (i) a temperature gradient (altitude), and (ii) a moisture gradient (wet Atlantic vs. moist Pacific slope). Most soils are Andepts, and residual, colluvial or derived from volcanic material. Humus layers are thicker on the wetter Atlantic slope. A total of 431 vascular plant species consisted of 86 pteridophytes, 1 gymnosperm, 296 dicots and 48 monocots. Species richness, canopy height and stem diameter decrease with increasing altitude, while the canopy surface becomes more flattend. A comparison with other studies shows that Chirripó's montane Quercus forests fit within the environmental ranges known from altitudinal zonations elsewhere in the Tropics. © 1995 Kluwer Academic Publishers.
Una nueva especie de Eugenia L. (Myrtaceae) de las selvas húmedas costarricenses
(Universidad de Costa Rica., 2004) Sánchez Vindas, Pablo
Se describe una nueva especie de Eugenia (Myrtaceae) de las veinte caribe de Costa Rica. Se distingue por las hojas con doble nervio marginal y los frutos acostillados y muy reticulado.
Hypoglycemic and antihyperglycemic effect of Witheringia solanacea in normal and alloxan-induced hyperglycemic rats
(Elsevier, 2011) Herrera, Cristina; García Barrantes, Pedro M.; Binns, Franklin; Vargas, Marianela; Poveda, Luis Jorge; Badilla, Sandra
Witheringia solanacea is a small shrub that belongs to the Solanaceae family. The plant is used as an antidiabetic in Costa Rican herbal medicine. The aim of this study was to evaluate the hypoglycemic and antihyperglycemic activity of the aqueous extract of W. solanacea leaves in rodent models. About the materials and methods, a crude extract of W. solanacea leaves was prepared in boiling water and the aqueous filtrate was lyophilized. A single oral dose of 250, 500 and 1000 mg/kg of the extract was evaluated for hypoglycemic activity in a glucose tolerance test in normal rats and for antihyperglycemic activity in alloxan-induced (140 mg/kg) diabetic rats. The blood glucose level was determined at different times by the glucose oxidase method. It Result in a Dosage of 500 and 1000 mg/kg of the extract significantly decreased (p < 0.05) blood glucose levels in the glucose tolerance test in normal rats after 1 h, there was no significant difference observed at 250 mg/kg. Dose of 500 mg/kg of the extract significantly reduced (p < 0.05) blood glucose levels in alloxan induced hyperglycemic rats at 4 and 5 h. In Conclusion, in the present study, the hypoglycemic and antihyperglycemic potential of the W. solanacea was demonstrated in rats. These results give support to the traditional use of W. solanacea as antidiabetic herbal medicine.
Cuatro compuestos nuevos del extracto no polar de la planta Amyris brenesii (Rutaceae) de Costa Rica
(Universidad de Costa Rica., 2008) Chavarría, Max; Castro, Victor; Poveda, Luis; Murillo, Renato
El estudio fitoquímico de las partes aéreas de Amyris brenesii (Rutaceae) recolectadas en Río Cuarto, Grecia, Alajuela (Costa Rica) mostró la presencia de cuatro nuevos compuestos: la 6-hidroxi-6-O-(3-hidroximetil-3-metilalil)- angelicina 1, el 6-(N-acetil-etanamin) -2,2-dimetil-2Hcromeno 2, el lignano 2,5-deshidrohinokinina 3 y la N-acetil-O-(geranil)-tiramina 4. Adicionalmente se aislaron los lignanos hinokinina 5, y justicidina E 6, las cumarinas escopoletina 7 y marmesina 8, el ácido 24-moretenoico 9 y el O-(3,3-dimetilalil)-halfordinol 10. Las separaciones se llevaron a cabo mediante la aplicación de técnicas cromatográficas y la elucidación de las estructuras se realizó con la ayuda de técnicas espectroscópicas de Resonancia Magnética Nuclear (RMN) de una y dos dimensiones.
Carbon accumulation in aboveground and belowground biomass and soil of different age native forest plantations in the humid tropical lowlands of Costa Rica
(Universidad Nacional, Costa Rica, 2012) Fonseca, William; Alice, Federico E.; Rey Benayas, José
Generic or default values to account for biomass and carbon accumulation in tropical forest ecosystems are generally recognized as a major source of errors, making site and species specific data the best way to achieve precise and reliable estimates. The objective of our study was to determine carbon in various components (leaves, branches, stems, structural roots and soil) of single-species plantations of Vochysia guatemalensis and Hieronyma alchorneoides from 0 to 16 years of age. Carbon fraction in the biomass, mean (±standard deviation), for the different pools varied between 38.5 and 49.7% (±3 and 3.8). Accumulated carbon in the biomass increased with the plantation age, with mean annual increments of 7.1 and 5.3 Mg ha-1 year-1 for forest plantations of V. guatemalensis and H. alchorneoides, respectively. At all ages, 66.3% (±10.6) of total biomass was found within the aboveground tree components, while 18.6% (±20.9) was found in structural roots. The soil (0–30 cm) contained 62.2 (±13) and 71.5% (±17.1) of the total carbon (biomass plus soil) under V. guatemalensis and H. alchorneoides, respectively. Mean annual increment for carbon in the soil was 1.7 and 1.3 Mg ha-1 year-1 in V. guatemalensis and H. alchorneoides. Allometric equations were constructed to estimate total biomass and carbon in the biomass which had an R2 aj (adjusted R square) greater than 94.5%. Finally, we compare our results to those that could have resulted from the use of default values, showing how site and species specific data contribute to the overall goal of improving carbon estimates and providing a more reliable account of the mitigation potential of forestry activities on climate change.
Carbon accumulation in the biomass and soil of different aged secondary forests in the humid tropics of Costa Rica
(Elsevier, 2011-10-15) Fonseca, William; Rey Benayas, José María; Alice-Guier, Federico E.
Efforts are needed in order to increase confidence for carbon accounts in the land use sector, especially in tropical forest ecosystems that often need to turn to default values given the lack of precise and reliable site specific data to quantify their carbon sequestration and storage capacity. The aim of this study was then to estimate biomass and carbon accumulation in young secondary forests, from 4 and up to 20 years of age, as well as its distribution among the different pools (tree including roots, herbaceous understory, dead wood, litter and soil), in humid tropical forests of Costa Rica. Carbon fraction for the different pools and tree components (stem, branches, leaves and roots) was estimated and varies between 37.3% (±3.3) and 50.3% (±2.9). Average carbon content in the soil was 4.1% (±2.1). Average forest plant biomass was 82.2 (±47.9) Mg ha 1 and the mean annual increment for carbon in the biomass was 4.2 Mg ha 1 yr 1 . Approximately 65.2% of total biomass was found in the aboveground tree components, while 14.2% was found in structural roots and the rest in the herbaceous vegetation and necromass. Carbon in the soil increased by 1.1 Mg ha 1 yr 1 . Total stored carbon in the forest was 180.4 Mg ha 1 at the age of 20 years. In these forests, most of the carbon (51–83%) was stored in the soil. Models selected to estimate biomass and carbon in trees as predicted by basal area had R2 adjustments above 95%. Results from this study were then compared with those obtained for a variety of secondary and primary forests in different Latin-American tropical ecosystems and in tree plantations in the same study area
Determination of carbonyls and their sources in three sites of the metropolitan area of Costa Rica, Central America
(Springer Science+Business Media B.V, 2011-03-02) Herrera-Murillo, Jorge; Rojas Marín, José Félix; Rodríguez Román, Susana
Ambient levels of carbonyl compounds and their possible sources were studied at three places in the metropolitan area of Costa Rica, including a residential, an industrial, and a com mercial downtown area with high vehicular flow, during the periods of April–May and September– December 2009. Fifteen carbonyl compounds were identified in the ambient air, of which ace tone was the most abundant carbonyl, followed by formaldehyde and acetaldehyde. Concentra tions were highest in rainy season at all sites and lower in dry season. These decreases in concen tration are explained by the influences of both photochemical reactions and local meteorological conditions. The strong correlation between C1– C2 and C3 indicated a common origin for these carbonyls. The C1/C2 ratios varied between 0.49 to 1.05, values which can be considered typical of an urban area
Clinical observations and safety profile of oral herbal products, souroubea and platanus spp: a pilot-toxicology study in dogs
(Universidad Nacional, Costa Rica, 2014-04-07) Villalobos, Pedro; Baker, John; Sánchez Vindas, Pablo; Durst, Tony; Masic, Aleksandar; Arnasont, John
This pilot-study evaluated the toxicity and safety profi le of two herbal products Souroubea spp Botanical Blend (SSBB) and Platanus Tree Bark (PTB) after oral administration to dogs at elevated doses for 28 days. SSBB and PTB botanicals are the major active ingredients of Sin Susto, a novel natural product for the treatment of anxiety in dogs. Three healthy female dogs were administered elevated doses of either SSBB, PTB or a placebo and then monitored for the occurrence of any systemic and local adverse events. Data from this pilot-study revealed that SSBB and PTB had no untoward effects on the health of dogs and were deemed safe which enabled the design and execution of a larger controlled target safety and toxicology study for Sin Susto.
The life cycle carbon balance of selective logging in tropical forests of Costa Rica
(Wiley Periodicals, 2020-06-01) Alice-Guier, Federico E.; Mohren, Frits; Zuidema, Pieter A.
The effect of logging on atmospheric carbon concentrations remains highly contested, especially in the tropics where it is associated to forest degradation. To contribute to this discussion, we estimated the carbon balance from logging natural tropical forests in Costa Rica through a life cycle accounting approach. Our system included all major life cycle processes at a regional level during one rotation period (15 years). We used mass flow analysis to trace biogenic carbon. Data were gathered from all logging operations in the Costa Rican NWregion (107 management plants), a sample of industries transforming wood into final products (20 sawmills), and national reports. We estimated a surplus of −3.06 Mg C ha−1 15 year−1 stored within the system. When accounting for uncertainty and variability in a MonteCarlo analysis, the average balance shifted to −2.19 Mg C ha−1 15 year−1 with a 95% CI of −5.26 to 1.86. This confidence interval reveals probabilities of a net increase in atmospheric carbon due to harvesting although these are smaller than those from a system that acts as a reservoir. Our results provide evidence for the carbon neutrality of bio-materials obtained from natural forests. We found that anthropogenic reservoirs play a determinant role in delaying carbon emissions and that these may explain differences with previous carbon balance studies on tropical forest management. Therefore, the climate mitigation potential of forest-derived products is not exclusive to forest management, but measures should be considered throughout the processes of wood transformation, use, and disposal.
Concentration of PM10 in the Metropolitan Area of Costa Rica, Central America: chemical composition and potential sources
(Universidad Nacional, Costa Rica, 2010) Herrera-Murillo, Jorge; Rojas Marín, José Félix; Rodríguez Román, Susana; Báez Pedrajo, Armando
Measurements of metals and inorganic ions were carried out on PM10. Sampling was made in five sites distributed in San José, Heredia and Belén cities. Samples were collected using Thermo Andersen PM10 high volume samplers with glass fiber and quartz filters. The ions SO4 2- , NO3- , Cl- , F- , PO43- , NH4 + , K+ , Na+ , Ca2+, Mg2+ were analyzed by ion chromatography and in the case of metals V, Cu, Cr, Pb, Ni, Mn, Fe, Al using an atomic absorption spectrometer with a graphite furnace attachment. The results indicated that SO42- was the most abundant ion, and with respect to metals, Al and Fe had the highest concentration. Spearman correlation, applied to all data, showed a high correlation between SO42- , NO3- and NH4+ indicating a common anthropogenic origin. From the metal species that were assessed only Pb and Cu presented enrichment factors higher than 10, indicating an anthropogenic contribution. Particles collected in the industrial zone of Belén showed the highest level of acidity and metal content.
A regression analysis of Q'eqchi' Maya medicinal plants from southern Belize
(Universidad Nacional, Costa Rica, 2006) Sánchez Vindas, Pablo
Amiguet, V.T., Department of Biology, University of Ottawa, P.O. Box 450, Ottawa, Ont. K1N 6N5, Canada; Arnason, J.T., Department of Biology, University of Ottawa, P.O. Box 450, Ottawa, Ont. K1N 6N5, Canada; Maquin, P., Belize Indigenous Training Institute, Punta Gorda, Toledo District, Belize; Cal, V., Belize Indigenous Training Institute, Punta Gorda, Toledo District, Belize; Sänchez-Vindas, P., Herbario Juvenal, Universidad Nacional, Heredia, Costa Rica; Alvarez, L.P., Herbario Juvenal, Universidad Nacional, Heredia, Costa Rica
Estimación de la biomasa y carbono almacenado en un bosque primario intervenido de la zona protectora "El Rodeo", Costa Rica
(Universidad de Pinar del Río "Hermanos Saíz Montes de Oca", Cuba, 2019-09-01) Retana-Chinchilla, Luis; Méndez-Cartín, Ana Lucía; Sánchez-Toruño, Henry; Montero-Flores, William; Barquero-Elizondo, Ana Isabel; Hernández-Sánchez, Gustavo
En la Estrategia Nacional de Cambio Climático de Costa Rica se recalcó la importancia de los ecosistemas boscosos en la absorción y fijación de CO2, como un mecanismo para lograr la carbono-neutralidad. Esta investigación buscó estimar la biomasa y el carbono almacenado en los diferentes componentes del bosque, de tres sitios pertenecientes a la Zona protectora "El Rodeo", ubicada al oeste de San José, Costa Rica (coordenadas geográficas 9º 52' 9,56'' N y 84º 14' 84,20'' W). Se instalaron 12 parcelas temporales, donde se inventariaron los componentes: fustales (>10 cm d), latizales (5-9,9 cm d), necromasa, vegetación herbácea y hojarasca, para determinar las concentraciones de carbono existentes en cada uno, componentes que en su conjunto representan la cantidad potencial de carbono que puede ser liberado a la atmósfera o conservado y fijado en una determinada superficie. Con respecto al volumen de carbono del bosque, se determinó que el promedio acumulado en todos los componentes analizados es de 230,38 Mg/ha, por lo que se estima que el stock de carbono aproximado para toda la zona protectora "El Rodeo" es de 541 400,23 Mg. No obstante, el estudio elaborado evidenció una alta variabilidad en los contenidos de biomasa y carbono entre sitios y parcelas establecidas, debido a la amplia matriz del paisaje que genera heterogeneidad en el bosque.
Earthquake magnitude calculation without saturation from the scaling of peak ground displacement
(Geophysical Research Letters, 2015-06-02) Melgar, Diego; Crowell, Brendan; Geng, Jianghui; Allen, Richard; Bock, Yehuda; Riquelme, Sebastian; Hill, Emma; Protti, Marino; Ganas, Athanassios
GPS instruments are noninertial and directly measure displacements with respect to a global reference frame, while inertial sensors are affected by systematic offsets—primarily tilting—that adversely impact integration to displacement. We study the magnitude scaling properties of peak ground displacement (PGD) from high-rate GPS networks at near-source to regional distances (~10–1000 km), from earthquakes between Mw6 and 9. We conclude that real-time GPS seismic waveforms can be used to rapidly determine magnitude, typically within the first minute of rupture initiation and in many cases before the rupture is complete. While slower than earthquake early warning methods that rely on the first few seconds of P wave arrival, our approach does not suffer from the saturation effects experienced with seismic sensors at large magnitudes. Rapid magnitude estimation is useful for generating rapid earthquake source models, tsunami prediction, and ground motion studies that require accurate information on long-period displacements.
Ethnopharmacology of Souroubea sympetala and Souroubea gilgii (Marcgraviaceae) and identification of betulinic acid as an anxiolytic principle
(Elsevier, 2015-05) Puniani, Eva; Cayer, Christian; Kent, Pamela; Mullally, Martha; Sánchez-Vindas, Pablo; Poveda Álvarez, Luis; Cal, Victor; Merali, Zul; Arnason, John; Durst, Tony
The neotropical lianas Souroubea gilgii and Souroubea sympetala (Marcgraviaceae) were chosen for study as part of a phytochemical discovery strategy focusing on rare plant families in Central America. In participatory research, Q’eqchi’ healers in Belize reported the use of these plants to reverse psychological symptoms inflicted by witchcraft. Extracts of two Souroubea species showed significant anti-anxiety activity in the elevated plus maze, a standardized test paradigm. Bioassay guided isolation led to the active principle, the pentacyclic triterpene, betulinic acid, which had activity in the elevated plus maze at 0.5 mg/kg. Other phytochemicals isolated included α- and β-amyrin, 2-hydroxyursolic acid, taraxenyl trans-4-hydroxy-cinnamate, naringenin, methyl ursolate, eriodytiol, methyl 2-α-hydroxyursolate, methyl 2-α-hydroxymaslinate, methyl betulinate, and condrilla sterol.
Anti-inflammatory and antinociceptive activities of Loasa speciosa in rats and mice
(Elsevier, 2003) Badilla Baltodano, Beatriz; Arias, A. Y.; Arias, M.; Mora, G. A.; Poveda Alvarez, Luis
In the range of doses of 250–500 mgykg (given i.p.) the aqueous extract of Loasa speciosa leaves showed an inhibitory effect on leukocyte migration, and a reduction on the pleural exudate, as well as dose-dependent anti-inflammatory and peripheral antinociceptive activities.
Antifungal Saponins from the Maya Medicinal Plant Cestrum schlechtendahlii G. Don (Solanaceae)
(Wiley, 2015-12-15) Kim Ta, Chieu Anh; Guerrero-Analco, José A.; Roberts, Elizabeth; Liu, Rui; Mogg, Christopher D.; Saleem, Ammar; Otárola Rojas, Marco Antonio; Poveda Álvarez, Luis; Sanchez-Vindas, Pablo; Cal, Victor; Caal, Federico; Subramaniam, Rajagopal; Smith, Myron; Arnason, John
Bioassay-guided fractionation of the crude extract (80% EtOH) of the leaves of Cestrum schlechtendahlii, a plant used by Q'eqchi' Maya healers for treatment of athlete's foot, resulted in the isolation and identification of two spirostanol saponins (1 and 2). Structure elucidation by MS, 1D-NMR, and 2D-NMR spectroscopic methods identified them to be the known saponin (25R)-1β,2α-dihydroxy-5α-spirostan-3-β-yl-O-α-l-rhamnopyranosyl-(1 → 2)-β-d-galactopyranoside (1) and new saponin (25R)-1β,2α-dihydroxy-5α-spirostan-3-β-yl-O-β-d-galactopyranoside (2). While 2 showed little or no antifungal activity at the highest concentration tested, 1 inhibited growth of Saccharomyces cerevisiae (minimum inhibitory concentration (MIC) of 15–25 μM), Candida albicans, Cryptococcus neoformans, and Fusarium graminearum (MIC of 132–198 μM).
Inhibition of human pathogenic fungi by ethnobotanically selected plant extracts
(Deutschsprachige Mykologische Gesellschaft, 2003-02-14) Ficker, Christine E.; Arnason, J. T.; Sanchez Vindas, Pablo; Álvarez, L. P.; akpagana, koffi; Gbéassor, M.; De Souza, C.; Smith, M. L.
In this study, 36 extracts derived from 29 plant species selected using an ethnobotanical approach were tested for antifungal activity against a taxonomically diverse group of 13 human pathogenic fungi. We compared the inhibitory characteristics of these plant extracts with those of the commonly used antifungals, amphotericin B and ketoconazole, and the plant-derived antifungal, berberine. Several plant extracts, notably those from Zingiber officinale (ginger) and Juglans cinerea (butternut), had pronounced antifungal activity against a wide variety of fungi, including strains that were highly resistant to amphotericin B and ketoconazole. Further exploration of Z. officinale as an antifungal is warranted as this species is generally regarded as safe for human consumption.
A Selective Ion HPLC-APCI-MS Method for the Quantification of Pentacyclic Triterpenes in an Anxiolytic Botanical Dietary Supplement for the Animal Health Market
(Natural Product Incorporation, 2019) Liu, Rui; Carballo Arce, Ana Francis; Singh, Ranpreet; Saleem, Ammar ; Rocha, Marco; Mullally, Martha; Otarola-Rojas, Marco; Poveda Alvarrez, Luis; Sanchez-Vindas, Pablo; Garcia, Mario; Baker, John; Merali, Zul; Guerrero-Analco, José A.; Durst, Tony; Harris, Cory; Arnason, John
A new anti-anxiety dietary supplement was developed for the animal health market, by combining 2 triterpene containing botanicals, Souroubea sympetala (Marcgraviaceae) with Platanus occidentalis (Platanaceae) A validated method for a quality control of the botanical blend was achieved using HPLC-APCIMS. The method resulted in the detection and quantitative determination of betulinic acid (1), and ursolic acid (2) in P. occidentalis and 1, 2, lupeol (3), β-amyrin (4) and α-amyrin (5) in S. sympetala and the finished product ZentrolTM. Detections were at low ng on column for 1 and 2 and in low µg range for 3, 4 and 5 using calibration curves within 10-100 ng (R2 > 0.993). Recovery of spiked samples for all the recoveries observed were > 94%. Inter-day and intraday variations were 0.8-3.5% and 5-10.4%, respectively. These results indicate the suitability of the developed analytical method to detect and quantify triterpenes of raw materials used in the manufacture of natural health products

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