Mariana Peñuela

For over five decades, Colombia's armed conflict has constrained rural development, especially in the Territories Most Affected by the Armed Conflict (ZOMAC). Nonetheless, the agro-industrial sector offers significant potential for energy generation from non-conventional renewable sources, particularly biomass, estimated at over 500,000 TJ per year. This study assesses the economic feasibility of valorizing swine manure through anaerobic digestion in ZOMAC territories, promoting circular economy and sustainable development. Four operational and economic scenarios of biogas plants using upflow anaerobic sludge blanket reactors were evaluated through Net Present Value (NPV) and Discounted Payback Time (DPBT). Profitability was found to depend mainly on fiscal incentives and plant scale. Scenario 3, involving biogas upgrading to biomethane, achieved a positive NPV (0.03 million USD) and an Internal Rate of Return (IRR) of 12.7% under Colombian tax incentives (Laws 1715/2014 and 1819/2016), with a DPBT of 7.4 years. Doubling the processing capacity improved profitability (IRR = 26.8%, NPV = 1.1 million USD, DPBT = 4.2 years) and made electricity generation (Scenario 4) viable (IRR = 13.8%, NPV = 0.16 million USD). These findings highlight that fiscal incentives and scaling-up are decisive for achieving economic feasibility, environmental sustainability, and inclusive rural development in post-conflict Colombia.

To meet Colombia’s energy needs by 2050, a total installed capacity of 42 MW across its power generation infrastructure is required. To achieve this, transitioning to cleaner energy sources, such as biomass—a non-conventional renewable energy—is necessary. Biomass is a promising renewable source for thermal and electrical energy production. This study researched the production of biogas from swine manure using a UASB reactor to valorize this waste. Swine manure was collected every 20 days from a pig farm with a capacity of 200 sows, located in Santa Rosa de Osos, Antioquia. The flow rate was increased three times (1.30 L d⁻¹, 1.62 L d⁻¹, and 2.08 L d⁻¹) to reduce the hydraulic retention time (HRT) and enhance biogas production. The volatile and total solids, chemical oxygen demand (COD), alkalinity, and biogas composition were measured over one year. The proposed system achieved 87.40% COD remotion from the feed stream and generated a yield of 507 mLCH₄ g_VS⁻¹, with an HRT of 19 days and an OLR of 4.27 gCOD L⁻¹ d⁻¹. The reactor produced biogas with a CH₄ content of 67.7%, CO₂ content of 18.1%, and H₂S content of 1413 ppm. This study highlights the effectiveness of the UASB reactor for biogas production using swine manure as a substrate.

Cyanobacteria and microalgae represent promising sources for sustainable production of biofertilizers and biostimulants, which can improve crop yield and quality and contribute to food security. However, despite their potential, their exploration remains incomplete, hindered by technical and economic challenges that arise when attempting to scale up production. The primary focus of this review is to delve into the active chemical compounds responsible for the biofertilizing and biostimulating roles of cyanobacteria and microalgae. In addition, it explores the essential unit operations involved in transforming their biomass into potential bioproducts. Moreover, this review highlights studies that have employed cyanobacteria and microalgae as sources of biofertilizer in various crops, describing their mode of action and application. By integrating cyanobacteria and microalgae processing with other advanced biotechnological, the viability of these products for sustainable agriculture can be significantly enhanced.

Esta investigación evalúa la capacidad de adsorción de sulfuro de hidrógeno (H₂S) en tres materiales: lana de acero, varillas de hierro y compost (biofiltro). El biogás tiene aproximadamente 1.327 ppm de H₂S y los experimentos se realizan en una columna de adsorción con soporte para medir la capacidad de eliminación (CE). Los resultados muestran que la lana de acero, con valores entre 1.12 y 9.16 mg_H2S g_lana ^-1 h^-1, es la mejor respecto a los otros materiales y presenta una saturación 47 veces mayor respecto a las varillas. Del análisis de sensibilidad, donde se evaluó la eficiencia de remoción (ER) al variar el flujo de biogás y cantidad de material adsorbente utilizado, se obtiene que la lana no presenta diferencias significativas en ER cuando la cantidad utilizada es de 30 g. Se concluye que la ER es mayor en las varillas a pesar de que el comportamiento de varillas y compost es similar en ER.

Increasing energy demands around the globe require alternative sources of energy. Considering the large amount of agro-industrial and agriculture-related activities in Colombia, energy generation from biomass waste is a promising option to meet the energy needs of the country. Anaerobic digestion (AD) is a good alternative to use these wastes. In this study, several potential substrates for biogas generation using AD systems were identified through a literature review. Vinasses, palm oil industry residues, swine manure, coffee industry residues, and municipal solid wastes were found as potential substrates for AD. Considering factors such as composition, the amount of waste production, availability, and their relationship with important Colombian economic activities, three substrates were selected to perform biochemical methane potential (BMP) experiments. The selected substrates were swine manure (SM), palm oil mill effluent (POME), and coffee residues (CR). The obtained BMP values were 240, 465, and 314 NmLCH4/g VS, respectively. An analysis of kinetic parameters analysis was conducted for the BMP experiments, based on the logistic and Gompertz models. It was seen that the AD of SM starts faster than in the other evaluated substrates. Nevertheless, the overall methane production rate was the highest for POME, followed by CR. SM had the lowest methane production yield. The obtained values of BMP, kinetic parameters, and those collected during the literature review can be useful for the design and implementation of AD systems in Colombia. Moreover, attention should be paid to substrates such as POME, which have a high energy production potential.

Actividad antimicrobiana de cultivos de callos y suspensiones celulares de Thevetia peruviana

La importancia clínica e industrial del ácido clavulánico (AC) promueve la búsqueda de nuevas estrategias para aumentar su productividad a un menor costo. En esta contribución, se evaluó la producción de AC en dos cepas de referencia de Streptomyces clavuligerus (Sc), ATCC27064 y DSM41826; éstas se probaron en diferentes medios de cultivo; los rendimientos de producto y costo de los medios se usaron como criterios de selección. En promedio, ScATCC alcanzó una concentración de AC 1.6-veces mayor que ScDSM, en el medio de proteína de soya (ISP). Se optimizó el medio con un diseño experimental central compuesto, estudiando la influencia del ISP y K2HPO4 sobre la producción de AC. La concentración máxima de AC obtenida en el medio optimizado (56mg·L-1) estuvo cerca del óptimo teórico. Nuestros resultados confirman que medios de cultivo con fuentes de carbono como glicerol y/o almidón proporcionan las mejores condiciones para la producción de AC.

Cell suspension cultures of Thevetia peruviana were established under dark for 19 days to investigate kinetic behavior related to biomass, substrate, cardiac glycoside, polyphenols, reactive oxygen species and anti-oxidant activity. The results showed high biomass production (18.80gDW/L) as well as sucrose consumption in 7 days. Preferential glucose over fructose consumption was observed. Intracellular production of cardiac glycosides reached 2.58mg DE/gDW at day 19. Highest extracellular production was reached between day 2 and 7 (6.19mg DE/L). Highest extracellular phenolic content was 80.61 ± 5.16mg GAE/L at day 7. Intracellular phenolic content increased to 2.76 ± 0.14mg GAE/gFW at day 7 and remained constant until day 19. ROS production at day 7 could be related to sucrose and glucose total consumption. Pearson Product-Moment Correlation Coefficient (ρ) showed that the phenolic compounds in cell suspension cultures of T. peruviana were responsible for the observed anti-oxidant activity. All together, these results give the first steps in metabolic behavior in cell suspension cultures of T. peruviana. Se establecieron cultivos en suspensión de la especie vegetal Thevetia peruviana en oscuridad, durante 19 días, para estudiar el comportamiento cinético de producción de biomasa, consumo de sustrato, producción de glicósidos cardiotónicos, polifenoles, especies reactivas de oxígeno y actividad antioxidante. Los resultados mostraron una alta producción de biomasa (18,80g PS/L), al igual que consumo total de sacarosa, a los 7 días de cultivo. Se observó un consumo preferencial de glucosa sobre fructosa durante todo el cultivo. La producción de glicósidos cardiotónicos intracelulares alcanzó valores de 2,58mg ED/g PS, al día 19. La mayor producción extracelular (6,19mg ED/L), se alcanzó entre los días 2 y 7. El mayor contenido de compuestos fenólicos extracelular fue de 80,61 ± 5,16mg GAE/L, en el día 7. El contenido de compuestos fenólicos intracelulares incrementó a 2,76 ± 0,14mg AGE/gPF, al día 7 y se mantuvo constante, hasta el día 19. La producción de EROs, al día 7, puede estar relacionada con el consumo total de sacarosa y glucosa. El coeficiente de correlación producto-momento de Pearson (ρ) indicó que los compuestos fenólicos en cultivos celulares en suspensión de T. peruviana eran los responsables de la actividad antioxidante observada. En conjunto, estos resultados brindan las primeras bases relacionadas al comportamiento metabólico de cultivos celulares en suspensión, de T. peruviana.