Artículos científicos

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A botanical extract of Souroubea sympetala and its active principle, betulinic acid, attenuate the cortisol response to a stressor in rainbow trout, Oncorhynchus mykiss
(Elsevier, 2016-09-28) Mullally, Martha; Mimeault, Caroline; Otárola Rojas, Marco Antonio; Sanchez Vindas, Pablo; Garcia, Mario; Poveda Alvarez, Luis; Moon, Thomas W.; Gilmour, Kathleen M.; Trudeau, Vance; Arnason, John
The capacity of the traditional anxiolytic plant, Souroubea sympetala, and its bioactive principle, betulinic acid (BA), to lower cortisol levels in rainbow trout, Oncorhynchus mykiss, was investigated. Effects at the level of the cortisol-producing interrenal cells were investigated using an in vitro head kidney preparation. Head kidney tissue incubated with S. sympetala extract or BA produced significantly less cortisol in response to adrenocorticotropic hormone (ACTH) than cells incubated with ACTH alone; a 50% reduction in the cortisol response was predicted to occur at 43 μg mL− 1 extract or 71 μg mL− 1 BA. To investigate whether effects on interrenal cell cortisol production translated into effects at the whole-animal level, the plasma cortisol response to an acute stressor, confinement in a net, was assessed. Fish fed a commercial trout pellet diet supplemented with 1 mg kg− 1 fish BA for six days exhibited a significantly lower plasma cortisol response to the acute stressor than fish fed the unsupplemented diet. Collectively, these results demonstrate that S. sympetala and BA act on the interrenal cells of the hypothalamic-pituitary-interrenal (HPI) axis in rainbow trout to significantly attenuate the cortisol response to an acute stressor. These findings suggest that BA is of potential use in mitigating effects of exposure to the stressors commonly encountered in an aquaculture setting. Statement of relevance • Souroubea sympetala extract and betulinic acid reduced ACTH-stimulated cortisol production by head kidney tissue in vitro, with little or no evidence of cytotoxicity.• The cortisol response to an acute stressor was attenuated in rainbow trout fed a commercial diet supplemented with betulinic acid.• The cortisol-reducing properties of the S. sympetala extract and betulinic acid may be useful in mitigating effects of stress in aquaculture, particularly since, as natural products, they may raise less public concern with respect to human consumption.
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.
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).
Blown by the wind: the ecology of male courtship display behavior in orchid bees
(Ecological Society of America, 2017-02-01) Pokorny, Tamara; Vogler, Ira; Losch, René; Schlütting, Patrick; Juarez, Pedro; Bissantz, Nicolai; Ramirez, Santiago; Eltz, Thomas
Many insects rely on chemical signals to transmit precise information on the location, identity, and quality of potential mates. Chemical signals are often broadcasted at sites with physical properties that maximize signal propagation and signal transmission. Male neotropical orchid bees (Euglossini) perch and display on vertical branches and tree trunks in the forest to expose volatile blends (perfumes) that they previously collected from their environment. Previous studies have shown that the chemical composition of perfume blends is highly differentiated even between closely related species. However, variation in behavioral components of perfume exposure and male display remain poorly understood. We conducted a four-year study on orchid bee display sites (8 species) in pacific Costa Rica, using field observations along with chemical analysis and cage experiments to assess display niche partitioning among sympatric species. We evaluated the influence of physical factors (terrain, wind, light) on the distribution of perch sites and on display behavior, and tested a prediction of the sex pheromone-analogue hypothesis, i.e., that displaying males have above-average quantities or qualities of acquired perfumes. Males of different species displayed in the same general area and sometimes in close proximity to each other, but partitioned the display niche by selecting different perch diameters, display heights, and by displaying at different times of the day. Most perch sites were located inside the forest on elevated ground, especially along ridges, where stronger winds may help disperse perfume signals. Furthermore, the angular position of displaying males on perches was narrowly determined by wind direction, with males being positioned on the downwind side of the perch, where they would be most conspicuous to conspecifics approaching on an odor trail. Although our results generally support the hypothesis that perfumes serve as pheromone analogues, we did not find differences in the perfume composition of males caught at display perches and males captured at chemical baits. This suggests that, while chemical communication is an integral part of orchid bee display, male display activity is not determined by the history of, and success in, volatile acquisition. © 2017 by the Ecological Society of America
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
Chemical characterization of filterable PM2.5 emissions generated from regulated stationary sources in the Metropolitan Area of Costa Rica
(Elsevier, 2017-01-14) Herrera-Murillo, Jorge; Rojas Marín, José Félix; Mugica-Alvarez, Violeta; Solórzano Arias, David; Beita Guerrero, Víctor Hugo
Filterable PM2.5 concentrations and their chemical characterizations were analyzed for 67 boilers and 25 indirect furnaces located in the Metropolitan Area of Costa Rica from February 2014 to November 2015. The PM2.5 samples were characterized by their composition, focusing on trace elements, inorganic ions and organic and elemental carbon. The results of PM2.5 concentrations ranged from 72 to 735 mgm-3, with the highest concentrations found for sources using biomass fuel, particularly Type B boilers, and the lowest values for diesel boilers. Further speciation of fine particulate matter (PM) showed significant levels of vanadium and nickel for boilers that use heavy fuel oil (bunker); 4886 and 1942 μgm-3, respectively. Copper and manganese were the most relevant metals for biomass burning sources, due to plant absorption from the soil. As for ion concentration, sulfate presented the highest concentrations for biomass boilers and furnaces, whereas chloride only presented the highest concentrations for furnaces. To complete the balance, organic and elemental carbon (OC and EC) analyses were made, in which biomass burning sources presented values five times higher than oil fuels. A Spearman's correlation analysis was made for the data set, revealing significant relationships between heavy metals, sulfate, and fine PM with respect to heavy fuel oil. For the biomass sources, the correlations pointed to K, Na, Mn and, in some cases, oxygen.
Climatic and edaphic controls over tropical forest diversity and vegetation carbon storage
(Springer Nature, 2020-03-19) Hofhansl, Florian; Fuchslueger, Lucia; Silla, Fernando; Andersen, Kelly; Buchs, David; Fiedler, Konrad; Franklin, Oskar; Hietz, Peter; Chacón Madrigal, Eduardo; Jenking, Daniel; Morera Beita, Albert; Plutzar, Christoph; Dullinger, Stefan; Huber, Werner; Quesada, Carlos A.; Rammig, Anja; Schrodt, Franziska; Vincent, Andrea G.; Weissenhofer, Anton; Wanek, Wolfgang
Tropical rainforests harbor exceptionally high biodiversity and store large amounts of carbon in vegetation biomass. However, regional variation in plant species richness and vegetation carbon stock can be substantial, and may be related to the heterogeneity of topoedaphic properties. Therefore, aboveground vegetation carbon storage typically differs between geographic forest regions in association with the locally dominant plant functional group. A better understanding of the underlying factors controlling tropical forest diversity and vegetation carbon storage could be critical for predicting tropical carbon sink strength in response to projected climate change. Based on regionally replicated 1-ha forest inventory plots established in a region of high geomorphological heterogeneity we investigated how climatic and edaphic factors affect tropical forest diversity and vegetation carbon storage. Plant species richness (of all living stems >10 cm in diameter) ranged from 69 to 127 ha−1 and vegetation carbon storage ranged from 114 to 200 t ha−1. While plant species richness was controlled by climate and soil water availability, vegetation carbon storage was strongly related to wood density and soil phosphorus availability. Results suggest that local heterogeneity in resource availability and plant functional composition should be considered to improve projections of tropical forest ecosystem functioning under future scenarios.
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.
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.
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.
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
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.
Efficacy of Souroubea-Platanus Dietary Supplement Containing Triterpenes in Beagle Dogs Using a Thunderstorm Noise-Induced Model of Fear and Anxiety
(Multidisciplinary Digital Publishing Institute, 2021-04-03) Masic, Aleksandar; Landsberg, Gary; Milgram, Bill.; Merali, Zul.; Durst, Tony; Sánchez Vindas, Pablo; Garcia, Mario; Baker, John; Liu, Rui; Arnason, John
A novel botanical dietary supplement, formulated as a chewable tablet containing a defined mixture of Souroubea spp. vine and Platanus spp. Bark, was tested as a canine anxiolytic for thunderstorm noise-induced stress (noise aversion). The tablet contained five highly stable triterpenes and delivered 10 mg of the active ingredient betulinic acid (BA) for an intended 1 mg/kg dose in a 10 kg dog. BA in tablets was stable for 30 months in storage at 23 ◦C. Efficacy of the tablets in reducing anxiety in dogs was assessed in a blinded, placebo-controlled study by recording changes in blood cortisol levels and measures of behavioral activity in response to recorded intermittent thunder. Sixty beagles were assigned into groups receiving: placebo, 0.5×, 1×, 2×, and 4× dose, or the positive control (diazepam), for five days. Reduction in anxiety measures was partially dosedependent and the 1× dose was effective in reducing inactivity time (p = 0.0111) or increased activity time (p = 0.0299) compared with placebo, indicating a decrease in anxiety response. Cortisol measures also showed a dose-dependent reduction in cortisol in dogs treated with the test tablet.
Ethnobotany of immunomodulatory treatments used by the Q’eqchi’ Maya of Belize
(Springer Nature Link, 2019-04-25) Walshe-Roussel, Brendan; Otarola Rojas, Marco; Sánchez Vindas, Pablo; Pesek, Todd; Cal, Víctor; Arnason, John
Using a quantitative ethnobotanical methodology, we identified 107 plant species belonging to 49 families used by Q’eqchi’ Maya healers in the treatment of symptoms from 14 usage categories related to inflammation. The families with the largest number of medicinal species were Piperaceae, Araceae, Asteraceae, Fabaceae, and Adiantaceae with five or more medicinal species. Healer consensus for plant species was high, with 56 species (52%) being used by all the healers, and consensus for usage categories was also high, as informant consensus factor (FIC) values for each category were greater than 0.4.
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.
Gestión de los residuos peligrosos, especiales y prioritarios en Costa Rica, 2022-2023
(2025-03-11) Tania Vega Godínez
El presente artículo científico es producto de una investigación orientada a examinar la gestión de los residuos peligrosos, de manejo especial y prioritarios en Costa Rica. Con este propósito, se aplicó un diagnóstico y un análisis FODA que involucró a los actores directos, para su respectivo análisis y vista de oportunidades de mejora. La información se recopiló aplicando un proceso que integró las siguientes acciones: revisión de legislación, datos en línea y entrevistas con actores clave. El artículo destaca información detallada sobre legislación, clasificación y gestión de residuos, incluyendo la responsabilidad extendida del productor. Además, aborda la necesidad evidente de mejorar la fiscalización y coordinación interinstitucional, e implementar sistemas que permitan la trazabilidad de los datos. El análisis respaldado por consulta bibliográfica en la fase de discusión, concluye en la importancia de reglamentar residuos prioritarios, fijar metas y promover la responsabilidad del productor, así como mejorar el control y fiscalización de residuos peligrosos.
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.
Indigenous Ex Situ Conservation of Q'eqchi' Maya Medicinal Plant Resources at the Itzamma Garden-Indian Creek, Belize, Central America
(Springer Science, 2012-12-27) Audet, Patrick; Arnason, John; Audet, Patrick; Walshe-Roussel, Brendan; Cal, Victor; Caal, Francisco; Otárola Rojas, Marco Antonio; Sanchez Vindas, Pablo; Poveda Alvarez, Luis; Pesek, Todd; Arnason, John
The Itzamma Garden and Medicinal Plant Project is a collaborative effort focused on identifying traditionally important plants used by the Q'eqchi' Maya of southern Belize. The Garden represents a cornerstone of the project where these plant resources (~130 in total, of which 102 have been identified to the species level) are cultivated ex situ as a means of providing primary healthcare by traditional healers. Here, we present a comprehensive agro-ecological survey of the Garden describing the layout and cultivation scenarios, development challenges encountered, and associated implementation strategies for improving site practices. A general recommendation for the adaptation of this strategy to other localities is the thorough depiction of ecological features based on interactions with local practitioners, for example, leading to the effective cultivation of plants, the enhancement of soil, and the surveillance of crop nutritional status and medicinal potency. We consider that the 'ethnobotanical garden approach' could provide a collaborative 'working model' for rural development, especially indigenous communities interfacing with their local agro-ecosystems.

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