Evaluaciòn de la actividad antioxidante del aceite esencial foliar de Calycolpus moritzianus y Minthostachys mollis de Norte de Santander

Los antioxidantes artificiales son ampliamente utilizados en la industria de alimentos, sin embargo actualmente se investiga sobre los antioxidantes naturales, siendo esto último una tendencia mundial en la preferencia del consumidor. Los aceites esenciales foliares (AE) de las especies Calycolpus moritzianus y Minthostachys mollis, recolectadas en el departamento Norte de Santander (Colombia), fueron estudiados con el fin de caracterizar su composición química y determinar su actividad antioxidante. La extracción del AE se realizó por destilación por arrastre con vapor de agua y la identificación de los componentes mayoritarios se hizo por Cromatografía de Gases de Alta Resolución (CGAR). Para determinar la actividad antioxidante de los AE se utilizaron 2 métodos: Capacidad de atrapamiento del catión-radical ABTS+ y del radical DPPH.Los componentes mayoritarios encontrados para C. moritzianus fueron α-Pineno, Limoneno, Eucaliptol, α-Terpineol, trans-β-Cariofileno y Guaiol, mientras que para M. mollis (variedad de orégano) fueron Acetato de α-Eudesmol, Acetato de (-)-Isolongifolol, Germacreno-D, Eucaliptol y Pulegona.El AE Minthostachys mollis (orégano) presentó la mayor actividad antioxidante frente al método del catión-radical ABTS+ con un valor de IC50 (22.7 ppm) y el mayor valor de TEAC (estándar de referencia) equivalente a 631.72 µmoles de Trolox por cada gramo de aceite, actividad que podría estar asociada a los componentes mayoritarios del AE

Evaluación de la actividad antimalárica y citotóxica de Estirilquinolinas obtenidas a partir de 8-Hidroxiquinaldina con Aldehídos aromáticos

This study reports the synthesis of five (E)-Styrylquinolines (Q.1, Q.2, Q.3, Q.5, Q.6) and three O-alkylated derivatives (Q.1a, Q.6a, Q 6 b) and the evaluation of its antimalarial activity and cytotoxic in vitro -- For Styrylquinolines Perkin condensation reaction type from 8-hydroxyquinaldine with aromatic aldehydes was used -- Antimalarial activity was performed using the method Radioisotope with FCB-2 strains of Plasmodium falciparum (chloroquine-resistant) and for the cytotoxic activity the MTT method with HepG2 cells was employed -- Most compounds showed to be active antimalarial -- Those with higher activity were Q.3 (IC506.4μM) and Q.5 (IC5010.8 µM), although all of them were cytotoxic at concentrations above 1 µg / mL -- The structures of these compounds were confirmed using infrared spectroscopy techniques and MRI in one and two dimensionsEl presente estudio reporta la síntesis de cinco (E)-estirilquinolinas (Q.1, Q.2, Q.3, Q.5, Q.6) y tres derivados O-alquilados (Q.1a, Q.6a, Q.6b) y la evaluación de su actividad antimalárica y citotóxica in vitro -- Para obtener las estirilquinolinas se empleó la reacción de condensación tipo Perkin a partir de 8-hidroxiquinaldina con aldehídos aromáticos -- La actividad antimalárica se realizó empleando el método Radioisotópico con cepas FCB-2 de Plasmodium falciparum (resistente a la cloroquina) y para la actividad citotóxica se empleó el método del MTT con células HepG2 -- La mayoría de los compuestos mostraron ser activos antimaláricos -- Los que presentan mayor actividad son el Q.3 (IC50 6.4µM), y el Q.5 (IC5010.8 µM) aunque todos mostraron ser citotóxicos a concentraciones superiores a 1µg/mL -- Las estructuras de estos compuestos se confirmaron empleando técnicas espectroscópicas de Infrarrojo y Resonancia Magnética Nuclear en una y dos dimensione

Gestión del conocimiento. Perspectiva multidisciplinaria. Volumen 6

El libro “Gestión del Conocimiento. Perspectiva Multidisciplinaria”, Volumen 6, de la Colección Unión Global, es resultado de investigaciones. Los capítulos del libro, son resultados de investigaciones desarrolladas por sus autores. El libro es una publicación internacional, seriada, continua, arbitrada de acceso abierto a todas las áreas del conocimiento, que cuenta con el esfuerzo de investigadores de varios países del mundo, orientada a contribuir con procesos de gestión del conocimiento científico, tecnológico y humanístico que consoliden la transformación del conocimiento en diferentes escenarios, tanto organizacionales como universitarios, para el desarrollo de habilidades cognitivas del quehacer diario. La gestión del conocimiento es un camino para consolidar una plataforma en las empresas públicas o privadas, entidades educativas, organizaciones no gubernamentales, ya sea generando políticas para todas las jerarquías o un modelo de gestión para la administración, donde es fundamental articular el conocimiento, los trabajadores, directivos, el espacio de trabajo, hacia la creación de ambientes propicios para el desarrollo integral de las instituciones

EVALUACIÓN DE LA ACTIVIDAD ANTIOXIDANTE DE ESPONJAS MARINAS DEL CARIBE COLOMBIANO EVALUATION OF ANTIOXIDANT ACTIVITY OF MARINE SPONGES FROM THE COLOMBIAN CARIBBEAN

Los invertebrados marinos representan un componente importante de la biota oceánica y una fuente rica de compuestos nuevos y biológicamente activos, tales como antibacterianos, anticancerígenos, antiinflamatorios y antioxidantes, entre otros. En este trabajo se evaluó la actividad antioxidante de los extractos metanólicos de las esponjas marinas del Caribe colombiano: Amorphinopsis atlantica, Callyspongia vaginalis, Ircinia felix, Lissodendoryx carolinensis, Mycale microsigmatosa, Niphates erecta y Tedania ignis, frente al catión radical ABTS&bull;+, usando como referencia Trolox. Los ensayos preliminares realizados (100 &mu;g/ml) mostraron buena inhibición del radical (> 53%) con los extractos de A. atlantica (IC50 = 88,26 &mu;g/ml), M. microsigmatosa (IC50 = 59,80 &mu;g/ml) y I. felix (IC50 = 88,81 &mu;g/ml) y baja inhibición del radical (< 33%) para los extractos de las otras esponjas. Al evaluar la actividad antioxidante de las fracciones acuosa y de diclorometano obtenidas a partir de cada extracto metanólico seleccionado, se encontró que la mayor inhibición del radical fue presentada por la fracción acuosa de A. atlantica (IC50 = 58,75 &mu;g/ml), superando a la mostrada por el extracto metanólico de esta esponja, además, la menor inhibición fue la mostrada por la fracción orgánica de I. felix (IC50 = 120,49 &mu;g/ml), valor mucho mayor comparado con el del respectivo extracto. Los resultados encontrados sugieren la producción por parte de esponjas marinas del Caribe colombiano de sustancias capaces de inhibir la reactividad química de radicales orgánicos como el ABTS&bull;+.<br>Marine invertebrates are an important component of oceanic biota and a rich source of novel and biologically active compounds, such as anti-bacterial, anticancer, anti-inflammatory, and antioxidants agents, among others. In this study we evaluated the antioxidant activity of methanol extracts from marine sponges from the Colombian Caribbean: Amorphinopsis atlantica, Callyspongia vaginalis, Ircinia felix, Lissodendoryx carolinensis, Mycale microsigmatosa, Niphates erecta, and Tedania ignis against the radical ABTS&bull;+ cation, using Trolox as a reference. The preliminary tests performed (100 &mu;g/ml) showed good inhibition of the radical (> 53%) with extracts from A. atlantica (IC50 = 88.26 &mu;g/ml), M. microsigmatosa (IC50 = 59.80 &mu;g/ml), and I. felix (IC50 = 88.81 &mu;g/ml) and low inhibition of the radical (< 33%) to extracts from the other sponge species. Upon evaluating the antioxidant activity of aqueous fractions of dichloromethane obtained from each of the selected methanol extracts, we found that the greatest inhibition of the radical was obtained from the aqueous fraction of A. atlantica, (IC50 = 58.75 &mu;g/ml), exceeding that exhibited by the methanol extract of this sponge; in addition, the least inhibition was exhibited by the organic fraction of I. felix (IC50 = 120.49 &mu;g/ml), a value considerable greater when compared with the respective extract. The results suggest that marine sponges of the Colombian Caribbean are capable of producing substances that inhibit the chemical reactivity of organic radicals such as ABTS&bull;+

Mechanism of Antifungal Action of Monoterpene Isoespintanol against Clinical Isolates of <i>Candida tropicalis</i>

The growing increase in infections by Candida spp., non-albicans, coupled with expressed drug resistance and high mortality, especially in immunocompromised patients, have made candidemia a great challenge. The efficacy of compounds of plant origin with antifungal potential has recently been reported as an alternative to be used. Our objective was to evaluate the mechanism of the antifungal action of isoespintanol (ISO) against clinical isolates of Candida tropicalis. Microdilution assays revealed fungal growth inhibition, showing minimum inhibitory concentration (MIC) values between 326.6 and 500 µg/mL. The eradication of mature biofilms by ISO was between 20.3 and 25.8% after 1 h of exposure, being in all cases higher than the effect caused by amphotericin B (AFB), with values between 7.2 and 12.4%. Flow cytometry showed changes in the permeability of the plasma membrane, causing loss of intracellular material and osmotic balance; transmission electron microscopy (TEM) confirmed the damage to the integrity of the plasma membrane. Furthermore, ISO induced the production of intracellular reactive oxygen species (iROS). This indicates that the antifungal action of ISO is associated with damage to membrane integrity and the induction of iROS production, causing cell death

The invasive snail Melanoides tuberculata (Müller, 1774) (Gastropoda, Thiaridae) in the lower basin of the Sinú River, Córdoba, Colombian Caribbean

We record the invasive thiarid snail Melanoides tuberculata (Müller, 1774) for the first time in the lower basin of the Sinú River, Córdoba, Colombia. We counted 2,892 individuals and collected 38 specimens at 4 localities in the basin. The introduction of this species is suspected to have occurred in different ways, but human transport and the aquarium trade are the most probable pathways. The presence of this species in the Sinú River is especially important because of its potential spread to other river basins in the region.  

On the occurrence of Antillesoma antillarum (Grube, 1858) (Sipuncula, Antillesomatidae) on the south-central part of the Colombian Caribbean coast

We document here the first confirmed report of the sipunculan worm Antillesoma antillarum (Grube, 1858) based on freshly collected, taxonomically verified specimens from the south-central Colombian Caribbean coast. This species was encountered on massive coralline rocks, coral rubble, and coral boulder at San Antero. We briefly describe and illustrate this species and provide notes on its distribution, ecology, and habitat

On the occurrence of Antillesoma antillarum (Grube, 1858) (Sipuncula, Antillesomatidae) on the south-central part of the Colombian Caribbean coast

We document here the first confirmed report of the sipunculan worm Antillesoma antillarum (Grube, 1858) based on freshly collected, taxonomically verified specimens from the south-central Colombian Caribbean coast. This species was encountered on massive coralline rocks, coral rubble, and coral boulder at San Antero. We briefly describe and illustrate this species and provide notes on its distribution, ecology, and habitat

Antibacterial Screening of Isoespintanol, an Aromatic Monoterpene Isolated from <i>Oxandra xylopioides</i> Diels

The incidence of nosocomial infections, as well as the high mortality and drug resistance expressed by nosocomial pathogens, especially in immunocompromised patients, poses significant medical challenges. Currently, the efficacy of plant compounds with antimicrobial potential has been reported as a promising alternative therapy to traditional methods. Isoespintanol (ISO) is a monoterpene with high biological activity. Using the broth microdilution method, the antibacterial activity of ISO was examined in 90 clinical isolates, which included 14 different species: (Escherichia coli (38), Pseudomonas aeruginosa (12), Klebsiella pneumoniae (13), Acinetobacter baumannii (3), Proteus mirabilis (7), Staphylococcus epidermidis (3), Staphylococcus aureus (5), Enterococcus faecium (1), Enterococcus faecalis (1), Stenotrophomonas maltophilia (2), Citrobacter koseri (2), Serratia marcescens (1), Aeromonas hydrophila (1), and Providencia rettgeri (1). MIC90 minimum inhibitory concentration values ranged from 694.3 to 916.5 µg/mL and MIC50 values from 154.2 to 457.3 µg/mL. The eradication of mature biofilms in P. aeruginosa after 1 h of exposure to ISO was between 6.6 and 77.4%, being higher in all cases than the percentage of biofilm eradication in cells treated with ciprofloxacin, which was between 4.3 and 67.5%. ISO has antibacterial and antibiofilm potential against nosocomial bacteria and could serve as an adjuvant in the control of these pathogens

Isoespintanol Antifungal Activity Involves Mitochondrial Dysfunction, Inhibition of Biofilm Formation, and Damage to Cell Wall Integrity in <i>Candida tropicalis</i>

The growing increase in infections caused by C. tropicalis, associated with its drug resistance and consequent high mortality, especially in immunosuppressed people, today generates a serious global public health problem. In the search for new potential drug candidates that can be used as treatments or adjuvants in the control of infections by these pathogenic yeasts, the objective of this research was to evaluate the action of isoespintanol (ISO) against the formation of fungal biofilms, the mitochondrial membrane potential (ΔΨm), and its effect on the integrity of the cell wall. We report the ability of ISO to inhibit the formation of biofilms by up to 89.35%, in all cases higher than the values expressed by amphotericin B (AFB). Flow cytometric experiments using rhodamine 123 (Rh123) showed the ability of ISO to cause mitochondrial dysfunction in these cells. Likewise, experiments using calcofluor white (CFW) and analyzed by flow cytometry showed the ability of ISO to affect the integrity of the cell wall by stimulating chitin synthesis; these changes in the integrity of the wall were also observed through transmission electron microscopy (TEM). These mechanisms are involved in the antifungal action of this monoterpene