Biogas conversion into biopolymers: strategies to boost process performance

La humanidad se enfrenta en la actualidad a dos grandes desafíos que están estrechamente relacionados y que deben abordarse conjuntamente: la contaminación por plásticos y el cambio climático. Por un lado, reemplazar los plásticos convencionales y recalcitrantes por soluciones alternativas innovadoras y respetuosas con el medio ambiente es de suma importancia para paliar el devastador impacto medioambiental derivado del uso masivo del plástico, así como para mitigar las emisiones de gases de efecto invernadero (GEI) generadas en su producción. Por otro l ado, promover la gestión de residuos a través de biotecnologías consolidadas como la digestión anaerobia puede contribuir a la reducción de las emisiones de GEI al tiempo que se genera biogás como subproducto, una fuente de energía renovable por su alto contenido en metano y que, como otras renovables, contribuye a reducir la fuerte dependencia de la economía del planeta de los combustibles fósiles.Nowadays, mankind faces two major environmental challenges that are closely interconnected and should be tackled simultaneously: plastic pollution and climate change. On the one hand, innovation efforts devoted to the replacement of conventional recalcitrant plastics by environmentally friendly solutions are of utmost importance to mitigate the devastating environmental scenario caused by plastic pollution and to reduce greenhouse gas (GHG) emissions derived from their production. On the other hand, waste management via mature technologies such as anaerobic digestion can contribute to the reduction of GHG emissions while providing a renewable energy source (i.e. biogas) that will partially reduce the world dependence on fossil fuels.Departamento de Ingeniería Química y Tecnología del Medio AmbienteDoctorado en Ingeniería Química y Ambienta

Genome scale metabolic modeling reveals the metabolic potential of three Type II methanotrophs of the genus Methylocystis

Producción CientíficaGenome Scale Metabolic Models (GSMMs) of the recently sequenced Methylocystis hirsuta and two other methanotrophs from the genus Methylocystis have been reconstructed. These organisms are Type II methanotrophs with the ability of accumulating Polyhydroxyalkanoates under nutrient limiting conditions. For the first time, GSMMs have been reconstructed for Type II methanotrophs. These models, combined with experimental biomass and PHB yields of Methylocystis hirsuta, allowed elucidating the methane oxidation mechanism by the enzyme pMMO (particulate methane monooxygenase) in these organisms. In contrast to Type I methanotrophs, which use the “direct coupling mechanism”, Type II methanotrophs appear to use the so called “redox arm mechanism”. The utilization of the “redox arm mechanism”, which involves the coupling between methane oxidation and complex I of the respiratory chain, was confirmed by inhibition of complex I with catechol. Utilization of the “redox arm” mechanism leads to lower biomass yields on methane compared to Type I methanotrophs. However, the ability of Type II methanotrophs to redirect high metabolic carbon fluxes towards acetoacetyl-CoA under nitrogen limiting conditions makes these organisms promising platforms for metabolic engineering.Marie Curie grant H2020-MSCA-IF-2016 CH4BioVal (GA nº 750126).Junta de Castilla y León (Ref. Project VA281P18)Ministerio de Ciencia e Innovación (Proyect CLU 2017-09, CTM2015-70442-R

Continuous polyhydroxybutyrate production from biogas in an innovative two‐stage bioreactor configuration

Producción CientíficaBiogas biorefineries have opened up new horizons beyond heat and electricityproduction in the anaerobic digestion sector. Added‐value products such aspolyhydroxyalkanoates (PHAs), which are environmentally benign and potentialcandidates to replace conventional plastics, can be generated from biogas. Thiswork investigated the potential of an innovative two‐stage growth‐accumulationsystem for the continuous production of biogas‐based polyhydroxybutyrate (PHB)usingMethylocystis hirsutaCSC1 as cell factory. The system comprised twoturbulent bioreactors in series to enhance methane and oxygen mass transfer: acontinuous stirred tank reactor (CSTR) and a bubble column bioreactor (BCB) withinternal gas recirculation. The CSTR was devoted to methanotrophic growth undernitrogen balanced growth conditions and the BCB targeted PHB productionunder nitrogen limiting conditions. Two different operational approaches underdifferent nitrogen loading rates and dilution rates were investigated. A balancednitrogen loading rate along with a dilution rate (D) of 0.3 day−1resulted in the moststable operating conditions and a PHB productivity of ~53 g PHB m−3day−1.However, higher PHB productivities (~127 g PHB m−3day−1)wereachievedusingnitrogen excess at a D = 0.2 day−1. Overall, the high PHB contents (up to 48% w/w)obtained in the CSTR under theoretically nutrient balanced conditions and the poorprocess stability challenged the hypothetical advantages conferred by multistagevs single‐stage process configurations for long‐term PHB production.Ministerio de Ciencia e Innovación under (BES-2016-077160) contract and (project CTM2015-70442-R)Junta de Castilla y León and EU-FEDER program (UIC 315, CLU 2017-09

La gestión curricular estratégica como proceso de mejoramiento continuo en los campos de acción de la coordinación académica del Colegio de Bachillerato Técnico Mixto de Sabanalarga

El presente trabajo de grado es de tipo cualitativo con carácter de investigación – acción, desarrollado en el Colegio Bachillerato Técnico Mixto de Sabanalarga, en el que se determina un mejor encausamiento en los campos de acción de la Coordinación Académica, con una Gestión Curricular que fortalezca el trabajo en equipo, el desarrollo organizacional, la acción pedagógica y la participación de la comunidad educativa en el contexto del PEI para la optimización de los ambientes de aprendizaje, de acuerdo a los requerimientos de la normatividad educativa y los nuevos enfoques gerenciales. Por ello aparece descrito una sensibilización, diagnóstico e intervención de los estamentos educativos durante el proceso investigativo y la propuesta.This degree work is of a qualitative type with an action-research nature, developed at the Colegio Bachillerato Técnico Mixto de Sabanalarga, in which a better prosecution is determined in the fields of action of the Academic Coordination, with a Curricular Management that strengthens teamwork, organizational development, pedagogical action and participation of the educational community in the context of the PEI for the optimization of learning environments, according to the requirements of educational regulations and new managerial approaches. For this reason, a sensitization, diagnosis and intervention of the educational establishments is described during the investigative process and the proposal

Production of (R)-3-hydroxybutyric acid from methane by in vivo depolymerization of polyhydroxybutyrate in Methylocystis parvus OBBP

Producción CientíficaMethylocystis parvus OBBP accumulates polyhydroxybutyrate (PHB) using methane as the sole carbon and energy source. In this work, the feasibility of producing (R)-3-hydroxybutyric acid (R3HBA) via intracellularly accumulated PHB through depolymerization (in-vivo) was investigated. Results showed that a PHB to R3HBA conversion of 77.2 ± 0.9% (R3HBA titer of 0.153 ± 0.002 g L-1) can be attained in a mineral medium containing 1 g L-1 KNO3 at 30 °C with shaking at 200 rpm and a constant pH of 11 for 72 h. Nitrogen deprivation and neutral or acidic pHs strongly reduced the excreted R3HBA concentration. Reduced oxygen availability negatively affected the R3HBA yield, which decreased to 73.6 ± 4.9% (titer of 0.139 ± 0.01 g L-1) under microaerobic conditions. Likewise, the presence of increasing concentrations of R3HBA in the medium before the onset of PHB depolymerization reduced the initial R3HBA release rate and R3HBA yield.Junta de Castilla y León - Fondo Europeo de Desarrollo Regional (projects CLU 2017-09 and UIC 315)Agencia Nacional de Investigación y Desarrollo de Chile (projects ANID/CONICYT Fondecyt Regular 1211434 and ANID/CONICYT Fondecyt Regular 1190521)Comisión Nacional de Investigación Científica y Tecnológica - PCI (grant REDES190137

Optimization of nitrogen feeding strategies for improving polyhydroxybutyrate production from biogas by Methylocystis parvus OBBP in a stirred tank reactor

Producción CientíficaThe design of efficient cultivation strategies to produce bioplastics from biogas is crucial for the implementation of this biorefinery process. In this work, biogas-based polyhydroxybutyrate (PHB) production and CH4 biodegradation performance was investigated for the first time in a stirred tank bioreactor inoculated with Methylocystis parvus OBBP. Decreasing nitrogen loading rates in continuous mode and alternating feast:famine regimes of 24 h-cycles, and alternating feast:famine regimes of 24 h:24 h and 24 h:48 h were tested. Continuous N feeding did not support an effective PHB production despite the occurrence of nitrogen limiting conditions. Feast-famine cycles of 24 h:24 h (with 50% stoichiometric nitrogen supply) supported the maximum PHB production (20 g-PHB m−3 d−1) without compromising the CH4-elimination capacity (25 g m−3 h−1) of the system. Feast:famine ratios ≤1:2 entailed the deterioration of process performance at stoichiometric nitrogen inputs ≤60%.Ministerio de Ciencia, Innovación y Universidades (grant BES-2016-077160)Ministerio de Ciencia, Innovación y Universidades (project CTM2015-70442-R)Junta de Castilla y León (projects UIC 071 and CLU 2017–09

Biogas bioconversion into poly(3-hydroxybutyrate) by a mixed microbial culture in a novel Taylor flow bioreactor

Producción CientíficaBiogas-based biopolymer production represents an alternative biogas valorization route with potential to cut down plastic pollution and greenhouse gas emissions. This study investigated for the first time the continuous bioconversion of methane, contained in biogas, into poly(3-hydroxybutyrate) (PHB) by a mixed methanotrophic culture using an innovative high mass-transfer Taylor flow bioreactor. Following a hydrodynamic flow regime mapping, the influence of the gas residence time and the internal gas recirculation on CH4 abatement was assessed under non nutrient limiting conditions. Under optimal operational conditions (gas residence time of 60 min and internal gas recycling ratio of 17), the bioreactor was able to support a CH4 removal efficiency of 63.3%, a robust CH4 elimination capacity (17.2 g-CH4 m-3h-1) and a stable biomass concentration (1.0 g L-1). The simultaneous CH4 abatement and PHB synthesis was investigated under 24-h:24-h nitrogen feast/famine continuous operation. The cyclic nitrogen starvation and the Taylor flow imposed in the bioreactor resulted in a relatively constant biomass concentration of 0.6 g L-1 with PHB contents ranging from 11 to 32% w w-1 (on a dry weight basis), entailing an average PHB productivity of 5.9 g-PHB m-3 d-1 with an associated PHB yield of 19.8 mg-PHB g-CH4-1. Finally, the molecular analysis of the microbial population structure indicated that type II methanotrophs outcompeted non-PHB accumulating type I methanotrophs, with a heterotrophic-methanotrophic consortium enriched in Methylocystis, Hyphomicrobium, Rubinisphaeraceae SH PL14 and Pseudonocardia.Ministerio de Ciencia, Innovación y Universidades (project RTI2018-0-096441-B-I00)Erasmus+ International Master of Science in Environmental Technology and Engineering (project 2017-1957/001-001-EMJMD)Junta de Castilla y Leon - Fondo Europeo de Desarrollo Regional (grants CLU 2017-09 and UIC 315

Technologies for the bioconversion of methane into more valuable products

Producción CientíficaMethane, with a global warming potential twenty five times higher than that of CO2 is the second most important greenhouse gas emitted nowadays. Its bioconversion into microbial molecules with a high retail value in the industry offers a potential cost-efficient and environmentally friendly solution for mitigating anthropogenic diluted CH4-laden streams. Methane bio-refinery for the production of different compounds such as ectoine, feed proteins, biofuels, bioplastics and polysaccharides, apart from new bioproducts characteristic of methanotrophic bacteria, has been recently tested in discontinuous and continuous bioreactors with promising results. This review constitutes a critical discussion about the state-of-the-art of the potential and research niches of biotechnologies applied in a CH4 biorefinery approach.2019-12-122019-12-12Ministerio de Economía, Industria y Competitividad (Proyect CTM2015-70442-R)Junta de Castilla y León (UIC71

Sensitization in solid waste management through participatory action research

Con el avance de la globalización la producción de residuos sólidos ha aumentado de manera considerable afectando de manera considerable el medio ambiente, por tal razón el estudio tuvo como objetivo fomentar el manejo de residuos sólidos mediante la investigación como estrategia pedagógica apoyada en TIC. Metodológicamente estuvo orientado desde el enfoque cualitativo con un diseño descriptivo, utilizando técnicas de recolección de información como observación participante y diario de campo. La unidad de análisis estuvo conformada por ochenta (80) estudiantes de cuarto y quinto grado de la IED San José Sede Escuela Urbana de Niñas. Los principales hallazgos de la investigación dejaron como evidencia que a través de la implementación de la IEP apoyada en TIC los estudiantes se sensibilizaron frente a la problemática de contaminación ambiental, aprendieron sobre el manejo, recolección y clasificación de residuos sólidos.With the advance of globalization, the production of solid waste has increased considerably, affecting the environment; for this reason this study aimed to promote the management of solid waste through research as a pedagogical strategy. Methodologically, it was oriented from the qualitative approach, through a participatory-action research design, using research strategies for the realization of a participative diagnosis, which gave rise to a program of activities to respond to the results of the diagnosis. During the programming, systematized observation was used as a technique, which recorded the opinion of the participants in the process. The analysis unit was made up of eighty (80) fourth and fifth grade students from the IED San José Urban School for Girls. The main findings of the research left as evidence that through the implementation of the IEP students were sensitized to the problem of environmental pollution, learned about the management, collection and classification of solid waste

Effect of drying technique on the volatile content of ecuadorian bulk and fine-flavor cocoa

Cocoa (Theobroma cacao L.) is one of the most widely consumed edible seeds in the world affected by on-farm processing. This study investigated the effect of different drying techniques, namely oven drying (OD), sun drying (SD), and a modification of sun drying using black plastic sheeting (SBPD), on the volatile profile of fine-flavor and bulk cocoa varieties analyzed by HS-SPME-GC-MS. A total of sixty-four volatile compounds were identified in fresh and dried cocoa. As expected, the volatile profile was clearly modified after the drying step, showing strong differences among cocoa varieties, this factor and its interaction with the drying technique having greater influence according to the ANOVA simultaneous component analysis. A principal component analysis revealed a close relationship between the volatile content of bulk cocoa samples dried by the OD and SD techniques, whereas slight volatile modifications were perceived among fine-flavor samples dried using the three different techniques under study. Overall, the results provide the basis for the potential application of the simplest inexpensive SBPD technique in order to accelerate the drying process of sun drying and produce cocoa with similar (fine-flavor cocoa) or improved (bulk cocoa) aromatic quality to that formed using the traditional SD or the small-scale OD.Spanish Ministry of Science, Innovation, and Universities, through the postdoctoral contract Juan de la Cierva de Incorporacion;Competitive Fund for Scientific and Technological Research "FOCICYT"info:eu-repo/semantics/publishedVersio