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Las mariposas tronadoras (Hamadryas)
(Editorial San José, Museo Nacional de Costa Rica / Departamento de Historia Natural, CR, 1992) Monge Nájera, Julián
Las Hamadryas son mariposas medianas (5-8 centímetros de envergadura). Muchas tienen un patrón de manchas pequeñas en que predominan los colores pardo y azul. Se posan con las alas abiertas, como abrazando las ramas y troncos donde chupan savia fermentada. También beben jugos de frutas en descomposición, carroña y heces. A veces parecen perseguirse unas a otras en vuelos espirales, emitiendo fuertes sonidos llamados "clics". El documento reporta información sobre su ubicación biológica, reproducción, comportamiento como orugas, mecanismos de defensa, caracterización como pupas y más.
Guía para el adecuado desecho de colillas de cigarro
(2025) Gamboa Monge, María Paula; Ruíz Michelsen, Johann Marco; Ureña Bonilla, María Paz
"Mingo sin Colillas" surge en el marco de los proyectos de Iniciativas Estudiantiles de la Vicerrectoría de Acción Social, 2025. A través de una guía metodológica, se busca brindar herramientas para la gestión local de colillas de cigarro en el distrito central de Santo Domingo de Heredia, con el propósito de atender las problemáticas derivadas de estos residuos, tanto para las personas fumadoras como no fumadoras, mediante procesos de educación y sensibilización ambiental.
Protoplast isolation from different explant sources in pitahaya (Selenicereus costaricensis, Cactaceae): Insights from roots, callus, and shoot tissues
(2025-04-01) Viñas Meneses, María de los Ángeles; Gómez Zeledón, Javier; Acuña Gutiérrez, Catalina; Jiménez García, Víctor Manuel
Efficient protocols for protoplast isolation in succulent plants, including cacti, are limited. In this study, we developed a protocol for isolating protoplasts from different tissues of pitahaya (Selenicereus costaricensis), including in vitro shoots and roots, greenhouse shoots, and callus cultures. We analyzed the effects of tissue source on protoplast yield and optimized the protocol by evaluating factors such as the composition of the enzyme solution and its pH, cell wall digestion time, shaking speed, and sucrose concentration during purification. Callus cultures yielded the highest protoplast numbers (2.5 × 106 protoplasts/g fresh weight), followed by greenhouse plant shoots (1.6 × 106 protoplasts/g fresh weight), while in vitro roots yielded the lowest (< 4 × 104 protoplasts/g fresh weight). Calcium oxalate crystals, mainly raphides, were observed in purification solutions containing damaged protoplasts from in vitro and greenhouse shoots, indicating a presumed detrimental effect on protoplast integrity. Conversely, no crystals or mucilaginous cells were observed in protoplast preparations from in vitro roots and callus cultures, facilitating the recovery of intact protoplasts. Protoplasts isolated from in vitro roots and shoots could not be effectively purified. Notably, greenhouse shoots digested exclusively with food-grade pectinase produced relatively high protoplast yields.
Bioactive compounds profile and extraction yields in coffee (Coffea arabica L.) by-products: A comparative analysis using ethanol, methanol and acetone
(2025-06-18) Jiménez Gutiérrez, Yamileth Milena; Camacho Marín, Sebastián; Muñoz González, Alejandra; Viñas Meneses, María de los Ángeles; Irías Mata, Andrea Paola; Esquivel Rodríguez, Patricia
Coffee beverages are consumed worldwide and produce considerable quantities of by-products from industrial processing every year. The present study identified 20 bioactive compounds in fresh coffee (Coffea arabica L.) husk and mucilage extracts from industrial processing. Ultra-high performance liquid chromatography coupled with diode array detection and triple quadrupole mass spectrometer (UHPLC-DAD-TQ/MS) was used for the profile of phytochemicals. Using ethanol (EtOH) as a green solvent, the extraction efficiency was compared with acetone and methanol (MeOH). Higher concentrations of Hydroxybenzoic Compounds (HBC) were found in husk than in mucilage and can be efficiently extracted with EtOH at 70, 80 and 90 %, with no significant differences with MeOH and acetone. Vanillic acid can be efficiently extracted from husk when 80 and 90% EtOH is used. Rutin, an important non-anthocyanin Flavonoid Compound (FC) due to its health benefits, can be extracted at all concentrations of EtOH with equal results compared to acetone and MeOH. Ethanol seems to be a promissory ¨green¨ solvent for extracting phenolic compounds, achieving similar extraction yields when compared to acetone and MeOH. The coffee husk and mucilage extracts could be used in the food, pharmaceutical and other industries.
Polyphenols from common beans (Phaseolus vulgaris L.) with antimycotoxigenic potential against fumonisin B1
(2025-02-09) Viñas Meneses, María de los Ángeles; Irías Mata, Andrea Paola; Chacón Ordoñez, Tania; Quesada Grosso, Ricardo Enrique; Arce Villalobos, Kelvin Andrés; Holst Sanjuán, Andrea; Quesada Román, Jorge Isaac; Sandí Bolaños, Cinthia Isabel
Fumonisins, primarily produced by Fusarium verticillioides, are among the most prevalent mycotoxins in agricultural products. This study explores the antimycotoxigenic potential of polyphenols from grains of common beans against fumonisin B1 (FB1). While fungal growth was quantified on common bean grains, FB1 production was absent, in contrast with higher toxin levels on maize and rice grains. Key polyphenols, catechin, kaempferol, epicatechin, gallic acid, and quercetin, were identified and quantified only in bean grains. Bioassays revealed that these individual polyphenols did not completely inhibit FB1 production. However, when these polyphenols were combined, the inhibition of FB1 production reached levels comparable to those achieved with the polyphenol-rich extract from common beans, exceeding 95%. This suggests a potential synergistic effect. Gene expression analysis demonstrated that polyphenol-rich extracts from common beans effectively inhibited FB1 biosynthesis in the fungus. These findings could serve as a differentiator feature in common beans, promoting their consumption and paving the way for the development of natural strategies to mitigate FB1 contamination in food.