Syntrophic LCFA-degrading microbial ecosystems

Long-chain fatty acids (LCFA) are energy-rich compounds, which are abundantly present in raw and waste materials. Thus, wastewaters that contain LCFA may yield high levels of methane in an anaerobic digestion process. Biogas formation from LCFAcontaining wastewater is a sustainable technology that warrants further investigation, specifically in terms of more fundamental microbiological aspects. The aim of this work is to get more insights into the syntrophic microbial communities that degrade LCFA anaerobically. Bacterial shifts of a mesophilic sludge incubated in the presence of palmitic, stearic or oleic acid was estimated by means of automated ribosomal intergenic spacer analysis (ARISA). Slightly differences were observed between the communities incubated with saturated LCFA (palmitic and stearic acids) and the ones of the blank assay. On the other hand, evident changes were found between ARISA profiles of the communities that were incubated with oleic acid and the ones obtained for the blank assay. These results suggest that the microbial communities that degrade saturated fatty acids are very close to each other and different from the ones that degrade unsaturated fatty acids

Efficient methane production from lipid-rich wastewater in high-rate anaerobic treatment

In this work, high rate anaerobic mineralization of a synthetic dairy effluent containing 50% COD as oleic acid was accomplished in two reactors operated in parallel. The anaerobic reactors were able to accommodate organic loading rates up to 21 kg COD m-3 day-1, HRT of 9 hours, attaining 99% of soluble COD removal efficiency and methane yield higher than 70%. Long chain fatty acids (LCFA) accumulated inside the reactor only during the last two phases of operation and palmitic acid was the main LCFA quantified, representing 40–100% of the total LCFA detected. High specific methanogenic activity was determined at the end of the operation, in the presence of acetate (1346±87 mg COD-CH4 gVS-1 day-1) and H2/CO2 (3582±309 mg COD-CH4 gVS-1 day-1). The specific activity of the anaerobic consortia present in the reactors during the operation was also determined, and a maximum value of 1170±170 mg COD-CH4 gVS-1 day-1 was obtained. The high performance accomplished in the reactors was a consequence of the discontinuous acclimation strategy applied, that produced an anaerobic microbial community specialized in the efficient mineralization of LCFA.Fundação para a Ciência e Tecnologia (FCT) projecto FAT-METHANE (POCTI/CTA/46328/2002), bolsa de doutoramento SFRH/BD/24256/200

El rol del control personal en la función paliativa de la justificación del sistema entre la población indígena y no indígena de estudiantes peruanos

Indexación: Scopus.In this article we propose a mediation model for the association between system justification and psychological well-being (i.e., the palliative function of ideology), based on system justification theory and compensatory control theory. Specifically, we argue that endorsing system-justifying beliefs leads to increased perceived personal control, which in turn predicts higher well-being. We used a convenience sample of students from two Peruvian universities. The results showed that system justification was related to general psychological well-being and personal control. In addition, indigenous students rated lower on system justification, general psychological well-being, self-esteem and personal control. Next, we found that the association between system justification and general psychological well-being was stronger among indigenous students, and this relationship was partially mediated by personal control. In addition, we showed that the mediation model is moderated by ethnicity, so that personal control is a mediator only among non-indigenous participants. We conclude that personal control is a mechanism involved in the palliative function of ideology among this group. Finally, we discuss possible explanations for the mechanisms involved in the palliative function of ideology among low-status individuals. © 2018, © 2018 Fundacion Infancia y Aprendizaje.En este artículo se propone un modelo de mediación de las relaciones entre la justificación del sistema y el bienestar psicológico (i.e., la función paliativa de la ideología) basado en las teorías de la justificación del sistema y del control compensatorio. En concreto, se propone que la adopción de creencias justificativas del sistema produce un aumento del control personal percibido que, a su vez, predice niveles más elevados de bienestar. En este estudio se utilizó una muestra por conveniencia de estudiantes provenientes de dos universidades peruanas. Los resultados muestran que la justificación del sistema está relacionada con el bienestar psicológico general y con el control personal. Además, los estudiantes indígenas mostraron niveles más reducidos de justificación del sistema, bienestar psicológico general, autoestima y control personal. También se observó que la relación entre la justificación del sistema y el bienestar psicológico general era más fuerte entre los estudiantes indígenas y que el control personal mediaba parcialmente en esta relación. Asimismo, mostramos que la etnicidad es un factor moderador del modelo de mediación, por lo que el control personal es un mediador únicamente entre los participantes no indígenas. El estudio concluye que el control personal es un mecanismo que interviene en la función paliativa de la ideología en este grupo. Por último, se discuten posibles explicaciones de los mecanismos implicados en la función paliativa de la ideología entre individuos de estatus social bajo.https://www.tandfonline.com/doi/full/10.1080/02134748.2018.153765

A Multiinstitutional Spanish Master’s Program in Ecosystem Restoration: Vision and Four-Year Experience

Since 2006, an innovative, multiinstitutional Spanish Master in Ecosystem Restoration (MER) is jointly offered by four major public universities in Madrid. In view of the high student demand—about 900 applications this academic year for only 30 places, a remarkable 75% rate of professional poststudy employment in a period of economic crisis, and the high number (> 40) of prestigious organizations involved in the program, we consider the MER program, although still young, to be very promising for the long term. We explain the process to create the MER and achieve the results obtained thus far. We describe its organization, report its vital statistics in terms of students, and identify some strengths and weaknesses observed to date. The MER program has evolved as a network of knowledge and experience that links universities, lecturers, researchers, students, private and public companies, NGOs, and administration centers. Our aim is to help other groups that may want to launch similar graduate-level ecological restoration degree programs

Assessment of methanogen survival in anaerobic enrichment cultures degrading long-chain fatty acids

Long-chain fatty acids (LCFA) are generally considered highly toxic towards methanogens. However, high methane yields have been obtained from high-load anaerobic digestion of LCFA, suggesting that methanogens can tolerate these compounds. In this work, hydrogenotrophic and acetoclastic methanogens were added to LCFA-degrading enrichments in order to evaluate their survival in the presence of unsaturated-LCFA (C18:1, oleate) and saturated-LCFA (C16:0, palmitate). Two hydrogenotrophs (Methanobacterium formicicum and Methanospirillum hungatei), and two acetoclasts (Methanosarcina mazei and Methanosaeta concilii) were tested. Oleate- and palmitate-enrichment cultures (OM and PM, respectively) were amended with each of the methanogens and incubated with 1 mM of the corresponding LCFA. Survival of methanogens after several transfers was evaluated by PCR-DGGE. For the hydrogenotrophs, results showed that M. formicicum survived in both OM and PM cultures, while M. hungatei only grew in the PM culture. Moreover, viability tests using live/dead staining coupled to fluorescent microscopy observation and cell counting indicated that M. hungatei is indeed more sensitive to oleate than M. formicicum. The percentage of damaged cells, caused by the exposure to low concentration of oleate (i.e. 0.5 mM), was very high in the case of M. hungatei (79%) contrasting with M. formicicum that was only slightly affected by this LCFA (8%). Regarding acetoclastic methanogens, both tested species prevailed in OM and PM cultures, although more abundant in PM enrichment. These results suggest that oleate is a more toxic compound for methanogens than palmitate. Nevertheless, all the methanogens studied, except M. hungatei, were found in the OM cultures

Molecular profiling of microbial communities in anaerobic bioreactors treating oleic acid rich wastewater

Fundação para a Ciência e a Tecnologia (FCT) - PTDC/BIO/69745/2006, POCTI/CTA/46328/2002, SFRH/BD/24256/2005, SFRH/BD/48960/200

Molecular profiling of microbial communities developed in high-rate anaerobic treatment of oleic acid rich wastewater

Fundação para a Ciência e a Tecnologia (FCT

Anaerobic microbial community dynamics during discontinuous treatment of a synthetic dairy wastewater

Background and aims: Anaerobic digestion is an opportunity to generate energy from treatment of effluents with high lipid content. Nevertheless, long-chain fatty acids (LCFA) usually accumulate within reactors causing biomass washout and microbial inhibition. Discontinuous operation was suggested as the optimal strategy to treat LCFA-rich wastewater. In this work, microbial community dynamics was investigated, during the discontinuous operation of an anaerobic reactor treating a synthetic dairy wastewater. Methods: An anaerobic lab scale reactor was operated in cycles, with OLR ranging from 4 to 8 kgCODm-3day-1. Feeding was composed of sodium oleate and skim-milk. Eight biomass samples were collected during the reactor operation and after DNA extraction, microbial community was studied by means of PCR-DGGE of the 16S rRNA gene fragments. Results: DGGE-fingerprints of Archaea and Bacteria showed that bacterial community was more affected by the operating conditions imposed than the archaeal one. Shifts in microbial community correlate well with the reactor performance and point out to microbial acclimation, since overall COD removal efficiency and methane yield increased along time up to 98% and 91%, respectively. Specific methanogenic acetoclastic and hydrogenotrophic activities increased from 2 and 56 mlCH4(STP)gVS-1d-1 at the beginning to 246 and 512 mlCH4(STP)gVS-1d-1 at the end of the operation, respectively. Conclusions: The results obtained show that the discontinuous operation applied promoted gradual development of a specialized microbial consortium able to efficiently treat LCFA-rich wastewater.Fundação para a Ciência e Tecnologia (FCT) - projecto BIOPOWER (PTDC/BIO/69745/2006

Screening vaccine formulations for biological activity using fresh human whole blood.

Understanding the relevant biological activity of any pharmaceutical formulation destined for human use is crucial. For vaccine-based formulations, activity must reflect the expected immune response, while for non-vaccine therapeutic agents, such as monoclonal antibodies, a lack of immune response to the formulation is desired. During early formulation development, various biochemical and biophysical characteristics can be monitored in a high-throughput screening (HTS) format. However, it remains impractical and arguably unethical to screen samples in this way for immunological functionality in animal models. Furthermore, data for immunological functionality lag formulation design by months, making it cumbersome to relate back to formulations in real-time. It is also likely that animal testing may not accurately reflect the response in humans. For a more effective formulation screen, a human whole blood (hWB) approach can be used to assess immunological functionality. The functional activity relates directly to the human immune response to a complete formulation (adjuvant/antigen) and includes adjuvant response, antigen response, adjuvant-modulated antigen response, stability, and potentially safety. The following commentary discusses the hWB approach as a valuable new tool to de-risk manufacture, formulation design, and clinical progression

Continuous high rate anaerobic treatment of oleic acid based wastewater is possible after a step feeding start-up

Mineralization of a synthetic effluent containing 50% COD as oleic acid was achieved in a continuous anaerobic reactor at organic loading rates up to 21 kg COD m−3 day−1, HRT of 9 h, attaining 99% of COD removal efficiency and a methane yield higher than 70%. A maximum specific methane production rate of 1170 ± 170 mg COD-CH4 g VS−1 day−1 was measured during the reactor’s operation. A start-up strategy combining feeding phases and batch degradation phases was applied to promote the development of an anaerobic community efficient for long chain fatty acids (LCFA) mineralization. Through the start-up period, the methane yield increased gradually from 67% to 91%, and LCFA accumulated onto the sludge only during the first 60 days of operation. For the first time, it is demonstrated that a step feeding start-up is required to produce a specialized and efficient anaerobic community for continuous high rate anaerobic treatment of LCFA-rich wastewater.Fundação para a Ciência e a Tecnologia (FCT) - POCTI/CTA/46328/2002, PTDC/BIO/69745/ 2006, SFRH/24256/2005European Commission (EC) - LIFE03 ENV/P/00050