No abstract

Los productos farmacéuticos (PFs) constituyen un grupo importante de los contaminantes emergentes (CE), debido a su potencial para inducir efectos fisiológicos adversos a bajas concentraciones en humanos y animales. Muchos estudios alrededor del mundo han reportado la presencia de un sin número de estos compuestos en diferentes medios acuáticos, lo que genera preocupación por los posibles efectos negativos que se producen en el agua, en la salud humana y la vida silvestre. En este contexto, este artículo tiene por objetivo presentar una revisión de los aspectos más relevantes sobre la presencia de PFs en el agua en un ámbito global desde el año 2010 hasta el 2019. El mayor número de estudios reportan presencia de contaminantes emergentes incluyendo fármacos de diferentes tipos en aguas superficiales, aguas subterráneas, aguas residuales y agua potable. Las principales fuentes de ingreso de fármacos en los sistemas acuáticos provienen de las aguas residuales que recogen aguas domésticas, efluentes hospitalarios y efluentes de fábricas sin tratamiento o inadecuadamente tratadas antes de ser liberadas a ríos y mares. La presencia de PFs en el ambiente acuático preocupa por su persistencia, la bioacumulación, la toxicidad y la generación de resistencia a antibióticos de muchos microorganismos, entre otras consecuencias aún no estudiadas en el ambiente.

Plastic polymers are petroleum-derived synthetic materials that have multiple uses in everyday life, but their excessive production has led to the accumulation of approximately 1,000 million tons of residues, causing negative ecological impacts. This study analyzed the biological degradation in liquid medium of polyurethane, polystyrene, and polyethylene samples by filamentous fungi isolated from Antarctica. The plastic samples were used without pretreatment or pretreated with an artificial aging UV chamber according to ASTM G155 for 500 h, inoculated or not with the Antarctic fungi (Penicillium, Geomyces, Mortierella species). Samples were incubated at 18°C for 90 days to determine potential fungal biodegradation. The physical-chemical and biological degradation of plastics were evaluated by analyzing the weight loss in function of time, and by determining possible changes in the chemical structure, using the technique of Fourier Transform Infrared Spectroscopy (FTIR). The polymers exposed to the artificial aging chamber resulted in the oxidative degradation of plastics (detected by morphological and structural changes), which favored their biodegradation. Out of the three fungal strains, Penicillium spp. presented the highest degradation percentage in aged plastics corresponding to 28.3% in polyurethane, and to 8.39 and 3.53% in polystyrene and low-density polyethylene, respectively.

In recent years, new data on the diversity of genera and species in the phylum Glomeromycota continue to be added and rearranged. Arbuscular mycorrhizal fungi are key to plant nutrition and agriculture. Studies report different short- and long-term cultivation practices that influence the abundance and diversity of Glomeromycota. To the best of our knowledge, there are no known studies of the fungal communities in the fine aroma cocoa cultivars. In this context, our work aims to discover the diversity of arbuscular mycorrhizae associated with two cocoa cultivation practices (conservative and semi-conservative) through the isolation of spores using microscopy and metabarcoding of the internal transcribed spacer region (ITS). Morphological analysis showed that the density of Glomeromycota spores exhibited significant differences between production systems. Although the metabarcoding analysis showed that diversity indices showed a higher increase in the roots than in the cocoa soil, independently of the cultivation practice. An abundance of 348 and 114 taxa were observed, corresponding to the conservative and semi-conservative practices, respectively. Seven genera were observed for the first time in cocoa crop agroforestry systems, including P. scintillans, R. diaphanus, R. fasciculatus, R. custos, D. disticha, M. perpusilla, and D. bernensis.