This study compares the properties and agronomic effectiveness of two organic fertilizers with different compositions: one derived from fresh animal manure (biol A) and the other from fruit-processing waste generated by juice shops (biol B), both obtained through strict anaerobic fermentation for 30 days. Physicochemical parameters, heavy metal content in the residual biomass, and the beneficial yeast microbial load of both biols were analyzed. Effectiveness was determined through foliar application at two dilution levels: 1:10 and 1:20 biol:water (v/v). Statistical analysis included ANOVA and X-R control charts. Biol A showed noteworthy concentrations due to its high content of P₂O₅ (2070 mg L⁻¹), K₂O (29,600 mg L⁻¹), and CaO (12,780 mg L⁻¹), but considerable levels of Pb in the biomass (22.75 mg kg⁻¹). Biol B showed concentrations of P₂O₅ (1820 mg L⁻¹), K₂O (25,480 mg L⁻¹), and CaO (10,530 mg L⁻¹), a higher yeast microbial load (7.43 × 10⁵ CFU mL⁻¹), and lower Pb content than biol A (1.43 mg kg⁻¹). In maize (Zea mays) trials, biol B at a 1:10 dilution (T1) resulted in the greatest growth after 21 days (height: 30.27 cm; stem diameter: 1.34 cm; leaves: 6.00 leaves), outperforming the control and biol A. It was concluded that substrate composition influences significant variations in biol properties; however, these differences are not as pronounced in agricultural practice. Biol B stood out for highlighting the potential of fruit residues for the production of safe and efficient biols.
En este estudio se sintetizaron tres aciltioureas que contienen en su estructura a la piperazina-1-carboxilato de etilo: 4-(benzoilcarbamotiol)piperazina-1-carboxilato de etilo (L1), 4((4-metilbenzoil)carbamotiol)-piperazina-1-carboxilato de etilo (L2) y 4-((3-nitrobenzoil)-carbamotiol) piperazina-1-carboxilato de etilo (L3). Se caracterizaron las propiedades físicas (punto de fusión y solubilidad) de cada ligando y se identificaron otras de sus propiedades por medio de técnicas instrumentales como análisis elemental, espectroscopia infrarroja (FT-IR), espectroscopia de resonancia magnética nuclear (1H-RMN y 13C-RMN) y espectroscopia fotoelectrónica de rayos X (XPS N1s). Después se realizaron pruebas de la actividad fungicida de los tres ligandos contra Aspergillus flavus usando la técnica de Kirby-Bauer en tres porcentajes de aplicación (0,5; 1,0 y 1,5%). Los resultados demostraron que los ligandos inhiben el crecimiento del hongo, esto recalca el papel de la modificación del anillo aromático en la actividad biológica y abre la puerta al desarrollo de nuevos agentes antifúngicos.
Con el objetivo de evaluar la calidad del aire en edificios públicos del distrito de San Juan de Lurigancho, Perú, se realizó una toma de muestras de la concentración de material particulado grueso (PM10) y fino (PM2,5) en seis puntos de monitoreo. La concentración promedio para el aire exterior (CPE) e interior (CPI) de PM10 fue de 43,87 y 36,43 µg/m3, respectivamente. Mientras que para PM2,5 fue de CPE = 18,29 y CPI = 16,30 µg/m3. Estadísticamente, la CPE y CPI mostraron asociación positiva entre el efecto del aire exterior en la calidad del aire interior. En la caracterización química del PM se identificó principalmente calcio (Ca), hierro (Fe), potasio (K), silicio (Si), sodio (Na) y aluminio (Al), con presencia de zinc (Zn) y plomo (Pb). En general, la concentración de PM no supera los límites establecidos en los Estándares Nacionales de Calidad Ambiental del Aire (ECA). Además, la caracterización química del PM sugiere como fuentes de emisión el polvo del suelo (Si, Al, Ca), los aerosoles marinos (Na, Cl) y la actividad industrial metalúrgica (Fe, Zn, Pb).
Coffee husk is an agro-industrial by-product with therapeutic potential due to its richness in bioactive compounds. This research aimed to evaluate the proximate composition and preliminary phytochemical profile, as well as the antioxidant capacity and exploratory hypoglycemic effect, of the husk from three Coffea arabica varieties: Acawa (A), Sarchimor (S), and Bourbon sidra (B). The phytochemical profiling, obtained through thin-layer chromatography (TLC) and high-performance liquid chromatography coupled to mass spectrometry (HPLC-MS), suggested a greater diversity of metabolites in the S variety, highlighting the presence of caffeine and phenolic compounds (chlorogenic acid derivatives, procyanidins, and mangiferin). Spectrophotometric methods demonstrated that varieties A and S exhibited the highest concentrations of total phenols, tannins, and the aforementioned alkaloid. The phenolic content correlated strongly and positively with the antioxidant capacity determined by the 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging assay (r = 0.972, p < 0.001) and the ferric reducing antioxidant power (FRAP) assay (r = 0.906, p < 0.001). The exploratory in vivo assay in mice using the S variety demonstrated a significant reduction in basal glycemia compared to the negative control (p < 0.05), although less pronounced than with glibenclamide. It is concluded that coffee husk exhibits antioxidant capacity and an incipient hypoglycemic effect derived from its complex matrix, which supports its potential utilization in the development of phytopharmaceuticals or as a functional ingredient in the food industry.
This study evaluated the potential for valorizing organic waste from the Restrepo's Marketplace in Bogot & aacute; through biogas production via anaerobic digestion (AD). The waste was classified into six groups according to its composition. pH, moisture, total solids (TS), volatile solids (VS), chemical oxygen demand (COD), total organic carbon (TOC), total nitrogen (TN), and phosphorus (P) were characterized. Once characterized, waste mixtures were formulated and optimized to achieve a carbon/nitrogen (C/N) ratio close to 25:1. Three batch AD treatments (4, 6, and 8 g of VS) were maintained at 30.00 +/- 2.50 degrees C for 41 days. Treatments 1 and 2 produced cumulative biogas volumes close to 1300 mL/g VS (p > 0.05), while treatment 3 produced less cumulative biogas (approximate to 810 mL/g VS). The post-digestion biosolid showed a reduction in TOC, an increase in alkalinity and TS, while TN remained stable. These findings confirm the feasibility of integrating waste from plazas into AD for sustainable energy production. The biosolid's compositional profile supports its use as a biofertilizer, promoting circular economy strategies based on green chemistry.
A new silver coordination compound, derived from tranexamic acid (TXA), was synthesized by reacting the ligand with a silver salt in an aqueous medium. The resulting product was isolated as a white solid with a 65% yield and was characterized by elemental analysis, Fourier transform infrared spectroscopy (FT-IR), carbon nuclear magnetic resonance (13C-RMN), and thermogravimetric analysis (TGA). From the synthesized complex, oil-in-water (o/w) creams were formulated at concentrations of 0,25; 0,50; 1,00 and 2,00%. The antibacterial activity was evaluated using the Kirby-Bauer agar diffusion method against Staphylococcus aureus. The 2,00% formulation showed the highest antibacterial activity, with an average inhibition zone of 13.785 mm. The results obtained indicate that the TXA-derived silver (I) complex has potential as an antibacterial agent for the development of topical formulations with pharmaceutical and dermatological applications.
In this work, we present the non-covalent functionalization of multi-walled carbon nanotubes (MWCNT) using an ethanolic extract of rosemary (Rosmarinus officinalis) via sonochemistry. Scattering assays, Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), and water droplet contact angle assay demonstrated the functionalization of the MWCNT. Furthermore, the cell viability assay (MTT) showed that the functionalized MWCNT exhibited a 14% improvement in cell viability compared to non-functionalized MWCNT in the NIH-3T3 cell line. The non-covalent functionalization of MWCNT using rosemary extract and ultrasound was demonstrated to be feasible for potential biomedical applications.
La cascarilla de café es un residuo agrícola generado durante el procesamiento de granos de café que, aunque puede incidir en la contaminación ambiental, contiene metabolitos con actividad antioxidante. En esta investigación se propuso evaluar la composición química y la capacidad antioxidante de la cascarilla de tres variedades de café (Coffea arabica): Catucaí rojo (CR), Catucaí amarillo (CA) y San Salvador (SS), cosechadas en la provincia de El Oro, Ecuador. Se cuantificó espectrofotométricamente el contenido de fenoles totales equivalente a ácido gálico y de taninos en los extractos hidroalcohólicos obtenidos mediante sonicación. Los resultados mostraron que las variedades CR y SS tenían niveles significativamente más altos de fenoles, la variedad CR también mostró mayor cantidad de cafeína. La cromatografía líquida de alta eficacia acoplada a espectrometría de masas (CLAE-EM) facilitó la identificación de dicha xantina, de ácidos clorogénicos y flavonoides, todos referidos para la especie. La capacidad antioxidante equivalente a Trolox, evaluada mediante los métodos de FRAP y DPPH, demostró que todas las muestras pueden ser aprovechadas por tal propiedad, ya que se evidenció una correlación fuerte y positiva con los contenidos de los compuestos fenólicos determinados. Estos hallazgos sugieren que la cascarilla de café puede ser una fuente valiosa de antioxidantes con potenciales aplicaciones en la industria farmacéutica y alimentaria.
La enfermedad de Alzheimer (EA) es la forma más común de demencia y consiste en un deterioro cognitivo y conductual que afecta principalmente a los adultos mayores. Se estima que, en los próximos 30 años, 115 millones de personas en todo el mundo estarán afectadas por esta enfermedad. Ante el aumento previsto de casos, los investigadores están buscando alternativas para controlar la EA. Un enfoque importante es el estudio de la proteína γ-secretasa, relacionada con la neurotoxicidad de los péptidos involucrados en la cascada amiloide, una vía bioquímica fundamental en el desarrollo de la EA. En este trabajo se realizaron estudios in silico con los fármacos JNJ-40418677, GSM-1, bexaroteno y trodusquemina para evaluar su eficacia como moduladores del sitio activo de la subunidad catalítica presenilina 1 (PSEN-1), que forma parte del complejo γ-secretasa. Según los valores de energía de afinidad obtenidos en el acoplamiento molecular, JNJ-40418677 fue identificado como el compuesto con mayor potencial de unión a PSEN-1, seguido de trodusquemina, bexaroteno y GSM-1. Los resultados obtenidos aportan información relevante sobre las características químicas y físicas básicas que deberán ser consideradas en el diseño de moléculas con potencial inhibitorio sobre la γ-secretasa que, como consecuencia, tendrían implicaciones en el tratamiento de la EA.
En este estudio se evaluaron las transiciones morfológicas en la agregación del ácido láurico en agua mediante simulaciones de dinámica molecular (DM) y utilizando el campo de fuerza GROMOS53A6 y el modelo de carga puntual simple (SPC). Para ello, se evaluaron sistemas con concentraciones variables de ácido láurico (de 1 a 80 moléculas) para analizar la formación, la estabilidad y los cambios estructurales de los agregados micelares. Los resultados mostraron que la morfología de los agregados depende de la concentración: a bajas concentraciones se formaron micelas esféricas, mientras que a mayores concentraciones se observaron estructuras elipsoidales. El radio de giro (Rg) y la excentricidad (e) confirmaron estas transiciones y se identificaron tres zonas de agregación. Además, se analizaron las interacciones tipo enlaces de hidrógeno, cruciales para la estabilidad micelar, mediante funciones de distribución acumulada (CDF). Este trabajo proporciona una visión a nivel molecular sobre el autoensamblaje de ácidos grasos, relevante para aplicaciones en nanotecnología y biomedicina.
To evaluate air quality in public buildings in the San Juan de Lurigancho district of Peru, samples of coarse (PM10) and fine (PM2.5) particulate matter concentrations were taken at six monitoring points. The average outdoor (CPE) and indoor (CPI) concentrations of PM10 were 43.87 and 36.43 & micro;g/m3, respectively. For PM2.5, CPE was 18.29 & micro;g/m3 and CPI was 16.30 & micro;g/ m3. Statistically, the CPE and CPI showed a positive association between the effect of outdoor air on indoor air quality. The chemical characterization of PM mainly identified calcium (Ca), iron (Fe), potassium (K), silicon (Si), sodium (Na) and aluminium (Al), with zinc (Zn) and lead (Pb). Overall, the PM concentrations didn't exceed the limits established in the national environmental quality standards (ECA). Furthermore, the chemical characterization of PM suggests that soil dust (Si, Al, Ca), marine aerosols (Na, Cl), and metallurgical industrial activity (Fe, Zn, Pb) are sources of emissions.
This study presents the development and validation of a quantitative method based on thin-layer chromatography (TLC) coupled with a UVP gel documentation system for the determination of the alkaloid taspine in Croton spp. latex. Taspine, a bioactive metabolite of pharmacological interest, was extracted and purified from samples collected in Chin & aacute;cota and Pamplonita (Colombia). A calibration curve was constructed by quantifying the pixel intensity of chromatographic bands analyzed with GelAnalyzer 19.1, and a polynomial model with a high coefficient of determination (R-2 > 0.99) was obtained. The method demonstrated excellent linearity, good reproducibility, and accuracy, confirmed by gas chromatography-mass spectrometry (GC-MS) validation. Taspine concentrations were 25.37 & micro;g/mL in Chin & aacute;cota and 10 & micro;g/mL in Pamplonita, with statistically significant differences (p < 0.05), suggesting environmental and genetic variability in metabolite production. The combination of TLC with digital documentation and software integration was validated as an accurate and reproducible alternative to instrumental methods and as a viable tool for phytochemical studies, particularly in resource-limited settings. This research is the first reported application of a validated TLC-image analysis method for taspine quantification.
This paper presents the results of the basic physicochemical characterization of the product and infusions derived from three popular commercial brands of yerba mate from Argentina and Brazil (Chamigo (R), Amanda (R), and Rei Verde (R)). From analysis it was observed that yerba mate Amanda (R) was found to have the highest caffeine concentration and the lowest moisture and ash contents, while yerba mate Rei Verde (R) had the highest levels of iron (II), total solids (TS), total dissolved solids (TDS), total suspended solids (TSS), and dust. Polyphenol analysis using the Folin-Ciocalteu method showed that all brands met the levels required by current legislation. Finally, an acceptance test was conducted on a sample of 50 people, with yerba mate Amanda (R) being the most frequently chosen brand.
This study reports an eco-friendly synthesis of zinc oxide nanoparticles (ZnO-NPs) using Rosmarinus officinalis L. leaf extract as a reducing and stabilizing agent. The extract was characterized by Fourier Transform Infrared (FT-IR) and Gas Chromatography-Mass Spectrometry (GC-MS). The biosynthesized ZnO-NPs were thoroughly characterized through UV-Vis spectroscopy showing a distinctive absorption peak at 372 nm, FT-IR confirms phytochemical capping, XRD reveals hexagonal wurtzite structure with crystallite size of 42.47 +/- 1.20 nm, and SEM/EDX exhibits spherical morphology with high purity. The ZnO-NPs exhibited dose-dependent antibacterial activity against Staphylococcus aureus (24.0 +/- 0.5 mm at 100 & micro;g/mL) and Escherichia coli (18.0 +/- 0.3 mm), outperforming the crude extract. Antioxidant assays, with ascorbic acid (vitamin C) as a positive control, demonstrated 89.2 +/- 2.1% DPPH inhibition (IC50 = 28.4 & micro;g/mL), comparable to ascorbic acid. Notably, ZnO-NPs showed 82.3 +/- 3.2% beta-haematin inhibition (50 & micro;M), surpassing chloroquine (68.1 +/- 2.8%), suggesting antimalarial potential. These findings highlight their potential as multifunctional therapeutic agents with a novel and promising antimalarial application.
In this study, a hybrid method (ultrasound/microwave) was used to extract bioactive compounds from Lavandula officinalis L. and Salvia rosmarinus L. A percentage yield of 19.84 % was obtained for Lavandula officinalis L., and 20.91 % for Salvia rosmarinus L. Using Fourier transform infrared spectroscopy (FTIR-ATR) and high-performance liquid chromatography-mass spectrometry (HPLC-MS), bioactive compounds such as rosmarinic acid, medioresinol, and caffeic acid were extracted from the plant samples, all of which have diverse applications in medicine. Furthermore, the extracts were found to possess antibacterial properties against Staphylococcus aureus and Escherichia coli, and to inhibit DPPH and ABTS free radical. Finally, an in vitro cell viability assay confirmed that the extracts are non-toxic to the porcine bone marrow cell line.
Sulfur (S) is used by many industries in the city of Guayaquil as an additive, intermediate product or raw material. However, their management can cause environmental impacts and respiratory health problems. The purpose of this study was to perform a stoichiometric analysis of the critical loads of atmospheric S deposits present in Guayaquil, Ecuador. Data was collected between 2018 and 2019 in 16 sites with high anthropogenic activity, the data was obtained with the application of passive samplers or throughfall traps. Stoichiometric reactions were then applied to recognize the concentrations of the analyte in the atmosphere and the impact it causes. The results showed that the oxidation of sulfur dioxide (SO2) generates sulfurtrioxide (SO3) in concentrations from 0.2285 to 0.7326 g. Likewise, between 1.36 x 10(-3) and 6.35 x 10(-3) g of sulfuric acid (H2SO4) were formed during the washing process, corresponding to the dry and rainy seasons in which the samples were collected, respectively. It was concluded that the SO2 present in the atmosphere undergoes changes when captured by the samplers, influenced by the different oxidative states of the S.
In this study, two methodologies (M-04 and M-10) were applied to extract and characterize lignin from the gamelote plant (Megathyrsus maximus), a plant widely available in tropical areas. Although the M-10 method yielded 22 +/- 2% w/w lignin, more than the M-04 method, both showed similar trends in Fourier transform infrared spectroscopy (FTIR), solubility, and surface tension. Carboxymethyl lignin (CML) was then synthesized from the extracted lignin; the yield for lignin obtained by both methodologies was 9% w/w. Analyses confirmed the improved properties of CML compared to lignin. Evaluating the interfacial properties, it was found that the lignin aggregation concentration is 3.6% w/w and that the emulsions (WOR 50:50 at pH 8.5) of lignins and CML have high conductivity, indicating that the modified biopolymer tends to be hydrophilic and can stabilize foams. CML stabilized 30:70 emulsions of water and diesel at pH 8.5. It was concluded that lignin presents promising properties for chemical modification and application in interfacial systems.
In this study, the moisture adsorption properties (GAB model) and thermodynamic characteristics-isosteric heat (Q(st)), entropy (triangle S), Gibbs free energy (triangle G), adsorption area (AS), and activation energy (Ea)- of potato tocosh flours, in natura (HTs), enzymatically hydrolyzed (HTe), and acid hydrolyzed (HTa), and of ginger flour (HJe) were compared. The influence of bioactive compounds (carbohydrates, phenols, and gingerols) on the hygroscopic behavior and stability of the materials was evaluated. HTa showed the highest monolayer moisture (X-0 = 0.1105-0.0982 g H2O/g d.s.), which decreased with temperature. HJe exhibited the highest GAB parameters (C and K) and Q(st) (55.9-54.77 kJ/ kmol), and a triangle S of 29.695 kJ/kmol K. Negative triangle G values indicated spontaneous adsorption. AS was highest for HTa (390.14 m(2)/g at 20 degrees C), while its Ea was the lowest (4.52 kJ/mol), reflecting rapid adsorption. Drying flours to X-0 and using impermeable containers are recommended, especially for HTa, due to their high exposed area. The results provide a scientific basis for optimizing the processing, storage, and industrial application of these flours in food and pharmaceutical products with nutraceutical potential.
The arrival of a global economy based on renewable energy and the adoption of green hydrogen (H2V) as an energy carrier have been consistently delayed. Although there is a wide range of applications for H2V, most of the technologies that produce or use H2V as fuel are expensive or have low maturity, which has limited market growth. In this context, synthetic fuels are positioned as an interesting alternative because they are carbon-neutral and allow the continued use of much of the existing infrastructure for fuel production, transportation, and consumption. Therefore, in this multicriteria study, we focused on comparing potential routes for producing the most attractive synthetic fuels-methane, methanol, and ammonia-from geothermal energy in the Costa Rican context. The results show that methanol is the best option because it enables the harnessing of volcanic CO2 . In the Latin American context, synthetic fuels could play a fundamental role in decarbonizing the economy and promoting innovation. For this reason, this study can serve as a basis for similar studies in the region.
Este artículo explica el proceso de diseño, construcción y evaluación del Metrostat, un potenciostato de bajo costo con Arduino para estudios electroquímicos. Para evaluar la relación costo-eficiencia, el Metrostat se comparó con un dispositivo comercial y con los dispositivos elaborados en otras investigaciones. También se realizaron experimentos de voltametría de barrido lineal, voltametría cíclica, polarización y cronoamperometría para evaluar el rendimiento del potenciostato. El equipo mostró una resolución en el potencial de 0,152 mV y en la corriente de 1,52 µA, comparables a los de un dispositivo comercial. La separación de las ramas en voltametría cíclica aumentó con la velocidad de barrido, en concordancia con la bibliografía consultada. Se obtuvieron voltamogramas cíclicos para la oxidación de ácido ascórbico a las concentraciones 2, 4 y 6 mM y curvas de polarización para la corrosión de acero al carbono similares a las reportadas en la bibliografía consultada. En cronoamperometría, se observó una relación lineal entre la corriente y la concentración de glucosa. Los resultados demuestran que el Metrostat tiene un rendimiento y sensibilidad comparables a los equipos comerciales a un precio considerablemente menor, esto lo convierte en una herramienta viable y eficiente para estudios electroquímicos en diversos campos como la química analítica, la ciencia de materiales y la bioquímica.
