Microbial degradation of aromatic hydrocarbons is an emerging technology, and it is well recognized for its economic methods, efficiency, and safety; however, its exploration is still scarce and greater emphasis on cyanobacteria–bacterial mutualistic interactions is needed. We evaluated and characterized the phenanthrene biodegradation capacity of consortium dominated by Fischerella sp. under holoxenic conditions with aerobic heterotrophic bacteria and their molecular identification through 16S rRNA Illumina sequencing. Results indicated that our microbial consortium can degrade up to 92% of phenanthrene in five days. Bioinformatic analyses revealed that consortium was dominated by Fischerella sp., however different members of Nostocaceae and Weeksellaceae, as well as several other bacteria, such as Chryseobacterium, and Porphyrobacter, were found to be putatively involved in the biological degradation of phenanthrene. This work contributes to a better understanding of biodegradation of phenanthrene by cyanobacteria and identify the microbial diversity related.

For several decades, the electrical admittance has been very useful for the determination of physical quantities, such as the characterization of some electrical properties of interest in organic samples. In this work, an electrical system based on graphite electrodes to determine the amount of living biomass of the cyanobacteria Fischerella sp. is proposed. Cyanobacteria are phototrophic microorganisms with applications on bioremediation, pharmaceutics, medicine, among others. The strain was characterized in BG-11 medium and cultured at different biomass concentrations. Samples were evaluated by electrical admittance and contrasted by the technique of dry weight in order to correlate the results registered by the/a proposal electric circuit. Scanning frequencies from admittance went in an order from 10 Hz to 1 000 000 Hz. Also, they showed a reproducibility, getting deviations of 6.45 × 10-5. This electrical system can be used to evaluate Fischerella sp. living biomass concentrations with high reliability.

Este trabajo describe una propuesta para estimar concentraciones de biomasa en cultivos de interés biotecnológico, por medio de los patrones de intensidad de luz esparcida. Para este estudio se implementó un sistema para realizar la adquisición de estos patrones, y se aplicaron técnicas de regresión polinomial y de vectores de soporte para estimar valores de concentración. Para determinar la efectividad de esta técnica se utilizó como instrumento de referencia un espectrofotómetro comercial. Los resultados obtenidos permiten observar similitudes de comportamiento de los parámetros del patrón de esparcimiento en comparación con la transmitancia y absorbancia medidos con espectrofotómetro. Los modelos de regresión obtenidos permiten solventar las limitantes de precisión del sistema de adquisición de patrones de intensidad de luz esparcida implementado.