Nanoparticles (NPs) have generated significant interest in various fields due to the unique properties that materials exhibit at the nanoscale. This study presents a comparative analysis of copper nanoparticles (Cu-NPs) and cobalt nanoparticles (Co-NPs) synthesized via conventional solvothermal and green hydrothermal synthesis using ethylene glycol and Medicago sativa extract, respectively. The conventional solvothermal synthesis showed higher efficiency for both Cu-NPs and Co-NPs with yields of 32.5% and 26.7%, respectively. Characterization through UV–visible spectroscopy (UV–vis), Fourier-transform infrared spectroscopy (FTIR) and atomic force microscopy (AFM) revealed that while solvothermal synthesis produced larger particles (76.5 nm for Cu-NPs, 86.8 nm for Co-NPs), the green hydrothermal method yielded smaller particles (53.8 nm for Cu-NPs, 67.7 nm for Co-NPs) with better control over particle size distribution and spherical morphology, showing minimal agglomeration. UV–vis confirmed metal oxide formation, while FTIR showed complex patterns in NPs (green hydrothermal), indicating plant extract compounds. Antifungal evaluation against Pseudocercospora fijiensis showed complete inhibition at 2000 ppm for both NP types, with no mycelial growth after 30 days. When integrated into chitosan, solvothermal NPs produced rougher surfaces, and scanning electron microscope (SEM) confirmed the presence of copper and cobalt in the nanocomposites. This study provides insights into the synthesis of nanoparticles using an environmentally friendly process and their microbiological applications for future use in organic agriculture.

El uso de biomasa como adsorbente constituye una alternativa potencial para la remoción de metales pesados presentes en aguas residuales industriales, lo cual representa un alto riesgo para el medio ambiente. En este trabajo se realizó la adsorción de Pb+2 y Cd+2 utilizando la cáscara de cacao como adsorbente en columnas y la simulación dinámica del proceso utilizando el software Aspen Adsorption® V10, con la finalidad de validar los resultados de la simulación y los obtenidos experimentalmente. Las curvas de ruptura del simulador y las experimentales convergen en casi toda la trayectoria, existiendo ligeras variaciones en el tramo final de la curva, coincidiendo los tiempos de ruptura para ambos metales, dando coeficientes de correlación (R2) de 0.984 y 0.998 para el Pb+2 y Cd+2, respectivamente, así como valores de error (SSE) inferiores al 5 %. Se analizó el efecto que produce la variación de la altura del lecho y el caudal en las curvas de ruptura; a medida que aumenta la altura del lecho y disminuye el caudal aumenta el tiempo de ruptura, favoreciendo la adsorción de ambos metales. Los resultados de esta investigación muestran la importancia del uso del software Aspen Adsorption® en el proceso de biosorción debido a la similitud con resultados experimentales, proporcionando su uso un ahorro de tiempo y recursos.

Aflatoxins are very potent toxic metabolites with carcinogenic, teratogenic, mutagenic, hepatotoxic and immunosuppressive effects, which constitute a potential risk to human health, so they should be considered as a latent problem that requires continuous examination in order to ensure food quality. This study was carried out with the objective of quantitatively determining the content of Aflatoxin M1 in three types of raw, pasteurized and ultrapasteurized milk consumed in the city of Cuenca-Ecuador, through thecomparative analysis of the High Performance Liquid Chromatography HPLC Techniques, after an extraction process in immunoaffinity columns and the ELISA Technique. Eighty-four samples were analyzed in three types of milk: raw, pasteurized and ultra-pasteurized, with the ELISA technique, none exceeded the detection limit of Aflatoxin M1(125 ppt or 0.125 ppb), established both by the national INEN: 9-10 in force and the parameters established by the Food and Agriculture Organization of the United Nations, Food and Drug Administration of the United States (0.5ppb) and with the High Performance Liquid Chromatography technique, 16 positive samples were found that were between the limit of detection and quantification (0.09 - 0.18 ppb.), obtaining a prevalenceof 19%, so that the High Performance Liquid Chromatography technique is more sensitive in the quantitative detection of the toxic metabolite Aflatoxin M1 in milk.