Artículos científicos
URI permanente para esta colecciónhttp://10.0.96.45:4000/handle/11056/14823
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Ítem Antioxidant and Antibacterial Potential of Passiflora edulis (Passion Fruit) at Three Ripening Stages for Waste Valorization(Multidisciplinary Digital Publishing Institute (MDPI) (Suiza), 2025) Quirós-Cubillo, Mariela; Valdés-Díaz, Sandra; Oviedo-Quirós, Juan; Álvarez-Valverde, Víctor; Syedd-León, RandallAbstract. This study evaluated the antioxidant and antibacterial potential of Passiflora edulis (passion fruit) at three ripening stages—intermediate, ripe, and overripe—to determine the optimal consumption time based on the presence of secondary metabolites (polyphenols, alkaloids, and anthocyanins). Fruits from Costa Rica, including pulp and peel, were analyzed. Qualitative assays (Dragendorff, Mayer, Lieberman Burchard, Ferric Chloride, and Shinoda) and quantitative analyses using Folin–Ciocalteu (total polyphenols), ORAC (antioxidant activity), and Kirby–Bauer (antibacterial activity) methods were conducted. Acetone–water (7:3) was the most effective solvent, with three extractions yielding optimal results. Peels contained significantly higher polyphenols (7.2 ± 0.1 mg GAE/g d.w.) and antioxidant activity (2403 ± 519 µmol TE/g d.w.) than pulps. Anthocyanins were abundant in both, while antibacterial activity was more effective in peels, inhibiting Gram-positive bacteria with 25% relative inhibition, but showing no activity against Gram-negative strains. These findings highlight passion fruit peel as a rich source of bioactive compounds with strong antioxidant and antibacterial properties, particularly in intermediate and overripe stages, supporting its potential use in the development of functional ingredients for nutraceutical applications and promoting sustainable waste management.Ítem Performance evaluation of a community-based water management organisation using integrated water quality monitoring(IWA Publishing (Reino Unido), 2024) López-Esquivel, Marian; Mena-Rivera, Leonardo; Sánchez-Gutiérrez, Rolando; Vega-Guzmán, Ilena; Swinscoe, Thomas H.A.Abstract. Community-based water management organisations (CBWMOs) play an important role in providing water services worldwide. However, there is some debate as to their capacity to sustain a safe drinking water supply considering the current socioeconomic and climate scenarios. Here, we present an integrated water quality assessment of the supply system of a CBWMO in Concepción of San Ramon, Costa Rica. Major ions, trace metals, and coliforms were analysed in the households and water sources over a 1-year period. The spring risk assessments and the water quality of the main river in the catchment were also carried out. We found that although the supplied water meets adequate standards, spatial and temporal changes in the water quality of the sources exist. Springwater composition is mainly driven by rock–water interaction processes, but early signs of potential anthropogenic pollution were found. The springs showed concentrations of NO3 - above natural levels and microbial contamination in 37 and 18% of the cases, respectively. River water quality showed a distinct composition, which is consistent with the anthropogenic pressures in the catchment. This study provides useful information on how water quality assessments can be used beyond regulatory processes to improve planning by CBWMOs to ensure water security.Ítem Not what it seems analytical validation and label accuracy of commercial CBD oils using HPTLC(Springer Nature, 2026-03-05) Morales Alfaro, Keilor; Zamora, Gabriel; Sandoval-Barrantes, Manuel; Carballo Arce, Ana Francis; Rodriguez-Corrales, Jose A.ABSTRACT. The rapid growth of the cannabidiol (CBD) market has raised concerns about product labeling accuracy and quality control. This study aimed to validate a high-performance thin-layer chromatography (HPTLC) method and apply it to analyze CBD content in commercial oils and e-liquids available in Costa Rica. The HPTLC method was validated following guidelines of the International Council for Harmonization of Technical Requirements for Pharmaceuticals for Human Use. Performance parameters assessed included linearity, accuracy, precision, specificity, and limits of detection (LOD), and quantification (LOQ). After validation, the method was used to quantify CBD and screen for other phytocannabinoids such as CBG, CBN, and Δ⁹-THC in 5 commercial oils and 3 e-liquids. The method showed excellent linearity (R² > 0.9998), precision (%CV < 2%), and accuracy (99–102% recovery), while successfully detecting CBD concentrations and qualitatively identifying other cannabinoids. Notably, some commercial samples showed CBD over- and underlabeling, and tentative presence of Δ⁹-THC. These findings reveal inconsistencies between the labeled and actual CBD content in several products, mirroring international trends, and represent the first documented evidence of mislabeling in hemp-based products in Costa Rica. The validated HPTLC method offers a cost-effective tool for regulatory surveillance, enabling preliminary cannabinoid profiling and quantification. Its application can support public health policies and consumer protection through improved product transparency and compliance with Costa Rica’s national hemp regulations.Ítem Extraction and Purification of Coumarins in Ipomoea cairica by TLC and HPLC: An Integrative Experiment for Student Learning Chromatography(ACS Publications (Estados Unidos), 2025) Álvarez-Valverde, Victor; Piedra-Marín, Gilberto; Alfaro-Avendaño, Rocío; Jiménez-Bonilla, Pablo; Borbón-Alpízar, HenryAbstract. Chromatographic techniques played a major role in several separation processes. In this work, an integrative laboratory practice is proposed in which students are expected to isolate scopoletin and umbelliferone from raw Ipomoea cairica. Thin layer chromatography (TLC), preparative chromatography (PC), and high-performance liquid chromatography (HPLC) techniques are applied to isolate phytochemical bioactive compounds. Scopoletin and umbelliferone are coumarins that have been reported to possess anti-inflammatory and antioxidant properties. These metabolites are found in high concentrations in Ipomoea cairica stems, and their methanolic extracts have shown larvicidal properties against Aedes aegypti. The experimental procedure includes fundamental extraction techniques such as liquid extraction and ultrasonic extraction. Additionally, it incorporates more advanced methods, such as chromatographic separation on a thin-layer plate, analytical detection of coumarins using HPLC with a diode array detector, and the isolation of coumarins through preparative plate chromatography. This laboratory experiment allows students to integrate and compare, in two laboratory sessions, the basic principles of TLC and preparative chromatography with more advanced techniques such as HPLC.Ítem El Quitosano: un aliado en el manejo de enfermedades en cultivos(Universidad Técnica Nacional (Costa Rica), 2024) Calvo Araya, José Alonso; Rojas Carrillo, Oscar; Vargas Martínez, AlejandroResumen. La utilización de biopolímeros como el quitosano en la agricultura es una alternativa eficiente y amigable en el manejo de enfermedades de cultivos, principalmente, desde un enfoque agroecológico y sostenibilidad donde hace uso de subproductos de la industria. Generalmente, la acción biocida está basada en inhibición de la germinación de los conidios de hongos, disrupción de la membrana celular de bacterias fitopatógenas, lo cual afecta la eclosión de huevos en nematodos fitoparásitos. Otros tipos de interacciones positivas que median en el control de fitopatógenos están en el crecimiento vegetal, inductor de resistencia en el hospedante, incremento de microorganismos degradadores de quitina en el suelo. En la siguiente revisión se aborda el concepto de quitosano, principales usos en el control de enfermedades, efecto sobre los principales grupos de microorganismos fitopatógenos, inducción de resistencia mediada por quitosano y nuevas aplicaciones en la agricultura. Actualmente, se demuestra que el uso de sustancias alternativas como es el quitosano muestra un buen control de agentes patógenos de plantas y cada vez es mayor su aceptación y utilización dentro del manejo integrado de enfermedades de cultivos. Por lo cual, el objetivo de esta revisión es examinar los principales aspectos relacionados al quitosano y como este es utilizado para controlar ya sea directa o indirectamente los problemas fitosanitarios en los cultivos.Ítem Eco-FriendlyMaterials Composed of Cellulose Fibers from Agave Bagasse with Silver Nanoparticles and Shrimp Chitosan(Tech Science Press (Estados Unidos), 2025) Sulbaran Rangel, Belkis; Caldera Siller, Jorge Armando; García Enríquez, Salvador; Anzaldo-Hernandez, José; Arratia-Quijada, Jenny; ESQUIVEL, MARIANELLYAbstract. In this research, the antibacterial properties of a composite material prepared from agave bagasse cellulose fibers doped with silver nanoparticles and chitosan were studied. The development of composite materials with antibacterial properties and environmentally friendly based on cellulose fibers from agave bagasse with silver nanoparticles prepared by green synthesis and chitosan from shrimp waste enhances the value of these agro-industrial wastes and offers the opportunity for them to have biomedical applications since these raw materials have been poorly reported for this application. The antibacterial properties of chitosan and silver nanoparticles are already known. However, the combination of silver nanoparticles with cellulose fibers and chitosan has been studied poorly. Green synthesis of silver nanoparticles was carried out, and spherical shape nanoparticles with a size between 20 and 50 nm were obtained by ultraviolet-visible (UV-Vis) spectroscopy and transmission electron microscopy (TEM) analysis. Additionally, in this research, the cellulose obtained from agave bagasse, the chitosan extracted from shrimp shells, and the composite material were characterized by infrared spectroscopy, mechanical analysis, and antibacterial tests. A decrease in the growth of Escherichia coli bacteria with 100% growth inhibition on cellulose, chitosan, and silver nanoparticles composite material and an increase in mechanical properties from 13.67 MPa of cellulose pure to 110 MPa of composite material was observed. These findings support the idea that the composite material has potential use in wound care dressings for antibacterial care.Ítem Mini review: Ethnopharmacology and phytochemistry of the tropical American family Marcgraviaceae(Frontiers Media S.A. (Suiza), 2025) Carballo Arce, Ana Francis; Villegas-Peñaranda, Luis Roberto; Garro-Álvarez, Raúl Esteban; Alfaro-Ureña, Yohana; Sandoval-Barrantes, Manuel; Mullally, Martha; Arnason, John ThorAbstract. The Marcgraviaceae is a neotropical family of lianas and shrubs that has received limited investigation for its medicinal properties. Characterized by prominent, nectar-rich terminal inflorescences, the family comprises 7 genera and 136 species. Traditional uses among Indigenous communities in the Americas include treatments for anxiety, sleep disorders, mental health conditions, and various dermatological ailments. Pharmacological and phytochemical studies have confirmed that extracts from the genus Marcgravia, traditionally used for dermatological conditions, inhibit bacterial quorum sensing, with active principles identified as naphthoquinones. Schwartzia brasilensis (syn. Norantea brasilensis) has demonstrated antiviral activity against Dengue virus, in vivo antimalarial efficacy, anti-inflammatory properties, and DNA-protective effects, but active principles remain to be accurately determined. Ruyschia phylladenia, containing triterpenes and isofraxidin, has shown promising antileishmanial, antibacterial, and antitumor activities. Pharmacological research on Souroubea spp. from Central America has revealed strong anxiolytic properties in animal models, with active compounds identified as the triterpenes betulinic acid, α-amyrin, and β-amyrin. Following toxicity and efficacy trials, Souroubea sympetala leaf extracts have been developed into a practical veterinary formulation for the management of noise aversion in dogs. Given the extensive diversity and wide distribution of this tropical American family, Marcgraviaceae offers considerable untapped potential for the discovery of new medicinal properties and phytochemicals.Ítem Regulating Nanotechnology: Ensuring Responsible and Safe Innovation in the Advancement of Science and Technology(Universidad de San Carlos de Guatemala (Guatemala), 2023) Jose-Roberto, Vega-Baudrit; Camacho, Melissa; Araya, Andrea; Corrales-Brenes, RebecaAbstract. Nanotechnology has significant potential in industries, medicine, and technology, but its rapid development raises concerns about health and environmental risks. Implementing regulations is crucial for responsible and safe use. Costa Rica has adopted policies and strategies, including standardization processes, to promote innovation and sustainable development. However, challenges and opportunities persist in implementing nanotechnology regulations. This article examines key challenges and opportunities, such as corporate culture, training, education, and international cooperation. It concludes that appropriate regulations can create significant opportunities for sustainable industry and economic development. Corporate culture barriers can be addressed through policies promoting social responsibility and sustainability. Training and education are essential for risk awareness and mitigation. International cooperation establishes global standards and prevents fragmented regulation. Implementing suitable nanotechnology regulations in Costa Rica fosters industry responsibility, enhances reputation and competitiveness, and stimulates investment in sustainable technologies. Despite challenges, it is vital to implement regulations for the responsible and safe use of nanotechnology.Ítem Consideraciones de los Desafíos Legales y Éticos en la Ingeniería de Tejidos y Dispositivos Médicos: Perspectivas y Estrategias para una Innovación Responsable en Life Sciences(LEAD University (Costa Rica), 2024) Jose-Roberto, Vega-Baudrit; Murrell, Manfred; Campos, Allan; Cordero, CinthyaResumen. Este artículo examina las dimensiones legales y éticas esenciales que deben considerar profesionales, investigadores y formuladores de políticas para equilibrar los avances científicos con la protección del paciente. Se discuten los marcos regulatorios actuales de la FDA en Estados Unidos y la EMA en Europa, y se analiza su adaptación a las necesidades cambiantes de la investigación y la aplicación clínica en la ingeniería de tejidos. Se exploran las implicaciones éticas del uso de material biológico humano, la edición genética, la privacidad de datos y el acceso equitativo a terapias emergentes. También se proponen estrategias para fomentar una innovación responsable, como el desarrollo de marcos regulatorios flexibles, la promoción del acceso equitativo y la implementación de una vigilancia efectiva.Ítem Nanotecnología en la Arquitectura: Una Visión Integral en el Uso de Nanomateriales(LEAD University (Costa Rica), 2024) Jose-Roberto, Vega-Baudrit; Juarez-Moreno, KarlaResumen. El presente trabajo explora el impa