Biodiesel is a mixture of monoalkyl esters of fatty acids derived from vegetable oils or animal fats. Agricultural residues are a potential source of raw materials for generating biofuels. The aim of this research was to determine the usefulness of Persea schiedeana Nees fruit as a potential source to be transformed into biodiesel by alkaline transesterification. In this sense, biodiesel was obtained using oil isolated from overripe fruits of P. schiedeana, damaged by the Heilipus lauri pest. The fruits were collected in the municipality of Huatusco, Veracruz, Mexico. The maceration of the fruits with hexane resulted in an oil with a high percentage of free fatty acids (8.36 ± 1.35%). The main components of the biodiesel were methyl oleate (53.12%) and methyl palmitate (25.74%). The dynamic viscosity of the biodiesel complies with ASTM D6751 and EN 14214 and the biodiesel blends with commercial diesel comply with ASTM D675, the calorific value showed an increase with increasing biodiesel concentration in the blends. This study demonstrates that the oil obtained from the overripe and surplus fruits of P. schiedeana is a viable feedstock for the production of a fuel to replace diesel.

Las condiciones de cultivo y el manejo poscosecha del cilantro y las fresas, propician su contaminación microbiana. Existen diversos procedimientos para desinfectar estos productos, sin embargo, es necesario establecer ventajas y desventajas de su aplicación. Los objetivos de este trabajo fueron comparar la eficacia de algunos tratamientos de desinfección para reducir la carga bacteriana en cilantro y fresa y evaluar las propiedades antioxidantes de dichos alimentos, antes y después de la desinfección. Los tratamientos de desinfección comparados fueron: ozono generado en un aparato electrodoméstico a un flujo de 6.25x10^-5 mol min^-1 y ozono obtenido en laboratorio mediante una reacción electrolítica a un flujo de 7.75x10^-7 mol min^-1. Asimismo, se utilizaron desinfectantes comerciales a base de dióxido de cloro, plata coloidal y dos productos obtenidos de extractos cítricos, uno aplicado después de un lavado con detergente (extracto estandarizado de semillas cítricas y glicerina) y el otro utilizado directamente (extracto de semillas cítricas a base de ácidos láctico y ascórbico). Posterior a los tratamientos de desinfección se llevó a cabo el conteo de unidad formadora de colonia y se determinaron los pigmentos característicos de los productos desinfectados, el contenido fenólico total y la capacidad antioxidante por el ensayo FRAP. Los resultados demostraron que el extracto estandarizado de semillas cítricas y glicerina resultó ser más efectivo (p< 0.05) para desinfectar tanto fresas como cilantro, al disminuir en 97 y 99.9% las unidades formadoras de colonias, respectivamente; sin embargo, redujo la concentración de antocianinas en fresas y la capacidad antioxidante en el cilantro.

Nowadays, strategies have been developed to enable online international and multicultural collaboration experiences. The Global Classroom (GC) project represents an advanced educational strategy that promotes international online collaboration. This experience brought together students of Biotechnology Engineering from the Tecnológico de Monterrey in Mexico with students of Chemical Engineering from the Universidad EAN in Colombia. These groups participated jointly in the Analytical Chemistry with Product and Process Design courses during the semesters from August to December 2020 and from February to June 2021, in two cohorts. At the heart of this collaboration was the implementation of online Project-Based Learning (PBL), designed to deepen students’ intercultural and technical educational experience. The core project involved an experimental study of the heat of reaction in the decomposition of hydrogen peroxide using an enzyme extracted from avocados at different stages of ripening. To evaluate the effectiveness of the GC program, three evaluation instruments were used: written reports, oral presentations, and anonymous surveys. The results of this assessment indicated a notable enrichment in several key competencies. Among them, teamwork stood out, where students learned to collaborate effectively despite cultural and location differences; problem-solving, encouraged by the challenging nature of the projects; and the exchange of ideas, which was enhanced by the diversity of perspectives and academic contexts. In addition, students showed an increase in the acquisition of new knowledge, successfully applied what they learned in previous scenarios, and optimized the use of computational and digital tools.