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Extracellular polymeric substances (EPS) are one of the main components of microbial biofilms, which are markedly influenced by the chemical composition and functional properties of these EPS. This study quantified the adherence capacity of 29 bacterial strains isolated from marine water in Luria–Bertani and Bushnel-Haas culture media. Their capacity to produce EPS and the influence of the culture conditions on the chemical composition and emulsifying activity of their synthesised exopolymers was determined. Eighteen of the bacterial strains in this study produced EPS while eleven were unable to do so. Surface adherence was associated with bacterial growth and with the capacity of the isolates to synthesise EPS. Pseudoalteromonas elyakovii W18 showed the highest values for surface adherence and synthesised a non-bioemulsifier EPS. Principal component analysis (PCA) was used to establish the relationships between the biopolymer characteristics and surface adherence. The efficient adherence of P elyakovii on the surface of K1 (Anoxkaldnes©) carrier was confirming by scanning electronic microscopy.

The objective of this study was the development and design of a treatment system at a pilot-plant scale for the remediation of hydrocarbons in industrial wastewater. The treatment consists of a combined approach of absorption and biodegradation to obtain treated water with sufficient quality to be reused in fire defense systems (FDSs). The plant consists of four vertical flow columns (bioreactors) made of stainless steel (ATEX Standard) with dimensions of 1.65 × 0.5 m and water volumes of 192.4 L. Each bioreactor includes a holder to contain the absorbent material (Pad Sentec polypropylene). The effectiveness of the treatment system has been studied in wastewater with high and low pollutant loads (concentrations higher than 60,000 mg L−1 of total petroleum hydrocarbons (TPH) and lower than 500 mg L−1 of TPHs, respectively). The pilot-plant design can function at two different flow rates, Q1 (180 L h−1 ) and Q2 (780 L h−1 ), with or without additional aeration. The results obtained for strongly polluted wastewaters showed that, at low flow rates, additional aeration enhanced hydrocarbon removal, while aeration was unnecessary at high flow rates. For wastewater with a low pollutant load, we selected a flow rate of 780 L h−1 without aeration. Different recirculation times were also tested along with the application of a post-treatment lasting 7 days inside the bioreactor without recirculation. The microbial diversity studies showed similar populations of bacteria and fungi in the inlet and outlet wastewater. Likewise, high similarity indices were observed between the adhered and suspended biomass within the bioreactors. The results showed that the setup and optimization of the reactor represent a step forward in the application of bioremediation processes at an industrial/large scale., Compañía Logística de Hidrocarburos S.A

An autotrophic nitrogen removal bioreactor with granular biomass was exposed to high antibiotics concentration in order to evaluate its impact over the performance and the biomass of this bioprocess. A mixture of azithromycin, norfloxacin, trimethoprim and sulfamethoxazole caused loss of autotrophic nitrogen removal performance, coupled to a deep change in the bacterial community diversity and structure of the granular biomass. Azithromycin, norfloxacin and trimethoprim were efficiently removed in the CANON bioreactor, reducing its concentration 77.9 ± 11.2%, 51.7 ± 10.7% and 57.8 ± 8.1%, respectively. The granular biomass changed significantly with the addition of the antibiotics, decreasing in settling velocity but increasing in compactness, losing its inner porous structure but developing a protective outer layer build of cell material. Prolonged operation under the antibiotics loading promoted the adaptation of multi-drug resistant fungus Scedosporium boydii fungal species and of Acidovorax ebreus TPSY , Alcaligenes aquatilis , Paracoccus versutus or Ochrobactrum antropii , which have been identified as human, animal and/or plant pathogens.

The addition of compost from sewage sludge to soils represents a sustainable option from an environmental and economic point of view, which involves the valorisation of these wastes. However, before their use as a soil amendment, compost has to reach the quality levels according to the normative, including microbial parameters. Viruses are not included in this regulation and they can produce agricultural problems and human diseases if the compost is not well sanitised. In this study, we carried out the analysis of the viral populations during a composting process with sewage sludge at an industrial scale, using semipermeable cover technology. Viral community was characterised by the presence of plant viruses and bacteriophages of enteric bacteria. The phytopathogen viruses were the group with the highest relative abundance in the sewage sludge sample and at 70 days of the composting process. The diversity of bacterial viruses and their specificity, with respect to the more abundant bacterial taxa throughout the process, highlights the importance of the interrelations between viral and bacterial communities in the control of pathogenic communities. These results suggest the possibility of using them as a tool to predict the effectiveness of the process.

This study describes the capacity of different sorbents to form stable biofilms under highly hydrocarbon-polluted conditions and the degrading capacity of the microbiota present in the biofilm. With this aim, microcosms were designed in a 1 L beaker with 400 mL of culture medium or polluted wastewater and an amount equivalent of 200 mL of the selected sorbent carrier, made of cork and/or polypropylene meltblown. The culturable bacteria adhered to the sorbent carrier were quantified, and the time course of the hydrocarbon concentration was studied together with the formation of a biofilm on the carrier’s surface. The results revealed a different performance of the carriers in terms of bacterial adhesion, significantly reduction in the hydrocarbon content in water at the end of the assays, and a biofilm tolerance to high hydrocarbon concentration in the polluted water. From these results, it was concluded that the use of a sorbent, hydrophobic cork, or meltblown polypropylene, together with indigenous microbiota, constitutes a promising technology for the treatment of hydrocarbon-polluted water.

López-Goñi, Ignacio et al., Social networks are already being exploited for searching, storing, and sharing knowledge, demonstrating that they are an efficient vehicle for social learning. Consequently, they could be implemented as a competent tool for formal learning. Twitter is among the 10 most popular online social networks, integrating a community of over 500 million users around the world. Twitter has already been used in several educational programs and evaluated as a positive teaching experience with an outstanding potential in academic and educational environments (1–6). However, there are scarce examples available in the literature about its use in science teaching and communication. In this work, we present and analyze the application of Twitter to create an online space for communication and learning of basic microbiology. With this aim, a team of professionals in the field has imparted, to our knowledge, the first worldwide open access microbiology course via Twitter. Here we assess the results of our experience of using this social network as a tool for teaching, promoting, and communicating scientific knowledge to a wide audience.