Microbial biosensors for wastewater monitoring: mini-review

Research on the use of microbial biosensors for monitoring wastewater contaminants is a topic that covers few publications compared to their applicability in other fields, such as biomedical research. For this reason, a systematic analysis of the topic was carried out, for which research-type articles were reviewed during the period 2012 to September 2022. For this, different search platforms were used, including PubMed, ScienceDirect, Springer Link, and Scopus, and through the use of search equations a relevant bibliography was located. After that, the research articles were selected based on exclusion criteria. As a result, it was found that, of the 126 articles, only 16 articles were strictly related to the topic, since there was a duplication of articles among the different databases. It was possible to demonstrate the usefulness of microorganisms as components of biosensors to monitor BOD, heavy metals, and inorganic contaminants in wastewater that also had a high sensitivity. Additionally, recombinant DNA techniques were shown to improve the performance of this type of biosensor and can finally be coupled to other emerging technologies, such as microbial fuel cells (MFCs). In conclusion, it was established that microbial biosensors have high acceptability and monitoring characteristics that make them a useful tool to detect low concentrations of pollutants in wastewater that can also provide results in real-time, thus generating forms of ecological safety and social responsibility in companies where wastewater is generated.Campus Trujill

Biodegradable potato starch films reinforced with aqueous extract of mango skin for use as active packaging [Películas biodegradables de almidón de papa reforzadas con extracto acuoso de piel de mango para su uso como envase activo]

En este trabajo se presenta el estudio del efecto de la incorporación de extracto acuoso de piel de mango (EPM) sobre las propiedades de películas biodegradables fabricadas a partir de almidón de papa y comprobar su potencial para ser usado como envase activo. El EPM fue añadido en el proceso de gelatinización en concentraciones de 5, 10 y 15% wt. Las propiedades de las películas fabricadas fueron caracterizadas usando Microscopía Electrónica de Barrido (MEB), Espectroscopía FTIR, cinética de absorción de agua y curvas Esfuerzo-Deformación. Las micrografías MEB muestran una formación con una superficie más lisa, sin vacíos ni grietas en las películas con EPM. Los análisis FTIR confirman la formación de bioplástico de almidón por la presencia de los grupos funcionales O-H, C-H, C-O y O=H. Por otro lado, se confirma que al añadir EPM se logra un aumento en la rigidez de las películas, pero una disminución en la elasticidad, sin embargo, no se afecta la capacidad de absorber agua. Este trabajo destaca los beneficios del uso de los residuos agrícolas y su potencial para la fabricación de materiales que podrían ser usados en la industria alimentaria como envase activo.In this work, the study of the effect of the incorporation of aqueous extract of mango skin (EPM) on the properties of biodegradable films made from potato starch is presented and its potential to be used as active packaging is presented. The EPM was added in the gelatinization process in concentrations of 5, 10 and 15% wt. The properties of the manufactured films were characterized using Scanning Electron Microscopy (SEM), FTIR Spectroscopy, water absorption kinetics and Stress-Strain curves. SEM micrographs show a formation with a smoother surface, without voids or cracks in EPM films. The FTIR analyzes confirm the formation of starch bioplastic by the presence of the functional groups O-H, C-H, C-O and O = H. On the other hand, it is confirmed that by adding EPM an increase in the stiffness of the films is achieved, but a decrease in elasticity, however, the ability to absorb water is not affected. This work highlights the benefits of the use of agricultural residues and its potential for the manufacture of materials that could be used in the food industry as active packaging