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Soil Organic Carbon Dynamics in Two Rice Cultivation Systems Compared to an Agroforestry Cultivation System

Valenzuela-Balcázar, Ibonne Geaneth | 2021-12-23

After changes in tillage on croplands, it is necessary to assess the effects on soil organic carbon (SOC) dynamics in order to identify if soil is a sink or emitter of carbon to the atmosphere. This study was conducted in two plots of rice cultivation, where tillage and water management changes occurred. A third plot of native forest with Cacao trees was used as reference soil (agroforestry). For SOC balance estimation, measurement of organic carbon (OC) inputs was determined from necromass, roots, microbial biomass, and urea applications. CO2 and CH4 emissions were also measured. Results showed that the change in the use of irrigation and tillage in rice cultivation did not cause significant differences in OC inputs to soil or in outputs due to carbon emissions. Further-more, it was found that both irrigation and tillage management systems in rice cultivation com-pared with agroforestry were management systems with a negative difference between OC inputs and outputs due to CO2 emissions associated with intense stimulation of crop root respiration and microbial activity. The comparison of SOC dynamics between the agroforestry system and rice cultivation systems showed that an agroforestry system is a carbon sink with a positive OC dynamic.

A Simulation Analysis of a Microalgal-Production Plant for the Transformation of Inland-Fisheries Wastewater in Sustainable Feed

García-Martínez, Janet B | 2022-01-16

The present research evaluates the simulation of a system for transforming inland-fisheries wastewater into sustainable fish feed using Designer® software. The data required were obtained from the experimental cultivation of Chlorella sp. in wastewater supplemented with N and P. According to the results, it is possible to produce up to 11,875 kg/year (31.3 kg/d) with a production cost of up to 18 (USD/kg) for dry biomass and 0.19 (USD/bottle) for concentrated biomass. Similarly, it was possible to establish the kinetics of growth of substrate-dependent biomass with a maximum production of 1.25 g/L after 15 days and 98% removal of available N coupled with 20% of P. It is essential to note the final production efficiency may vary depending on uncontrollable variables such as climate and quality of wastewater, among others.

Prospects for using wastewater from a farm for algae cultivation: The case of Eastern Colombia

Urbina-Suarez, Nestor Andres | 2021-05-24

: In recent years, the technical and economic feasibility of using microalgae and cyanobacteria has been explored for the removal and exploitation of domestic, agricultural and industrial residual effluents with high C, N and P compounds content. To contribute to the understanding of the process and its technical viability for microalgae growth, the article discusses monitoring, flow determination, and physicochemical characteristics of two types of effluents generated in an experimental farm located in the east of Colombia, before (R1) and after biological treatment (R2). In general, the results showed the reduction of different parameters, such as total dissolved solids (TDS), hardness, salinity and phosphates after treatment with activated sludge. However, the conductivity value obtained in R1 and R2 showed the presence of a pollutant load. These findings can be attributed to the highest concentration of fats and oils in the water during early hours of the day. Finally, although the concentration of nitrates increased from 46.63 to 225.21 mg∙dm–3 and phosphate decreased slightly from 9.65 to 6.21 mg∙dm–3, no inhibition was generated in the microalgae, as evidenced in the growth of the microalgal biomass in effluents after nitrate and phosphate removal above 80%.

Modelling of DHA Production from S. Limacinum ouc88: fed-batch perspectives

Contreras, B | 2021-09-12

Biotechnology and its need to improve industrial processes have shown the need for techniques that allow processes optimization. Computer simulation offers the advantage of determining production prospects without significant resources and experimentation time. That is why a kinetic study of DHA (docosahexaenoic acid) production from Schizochytrium limacinum OUC88 was developed in this investigation. Based on the above, a mathematical approach to simulate DHA production in a fed-batch model is proposed in this work, using Matlab software. The experimental data for determining kinetic parameters were taken from previous investigations, and a simulated DHA level in the fed-batch mode of 150 g/L was reached. On the contrary, the simulated results in batch mode present only a maximum value of 30 g/L, demonstrating the effectiveness of the fed-batch implementation with perspectives on improving processes.

Operating Mode Effect on Lipids Production from Rhodotorula mucilaginosa: Modelling and Simulation Trends

Gelves Gelves, Elizabeth | 2021-09-12

A sustainable alternative for fossil fuels substitution is the production of biodiesel from natural lipids. Mainly, such oil used is in the form of triglycerides and is characterized by being potentially renewable, non-toxic, and biodegradable, thus making it a sustainable product. For producing such biofuel, yeast oil is one of the most viable and currently known options, obtaining theoretically optimal results. In this article, kinetic parameters from the oleaginous yeast Rhodotorula mucilaginosa will simulate lipid accumulation capacity based on different bioreactor operating modes. Likewise, The Matlab software is used to simulate batch and continuous operating modes to establish comparisons between the productions obtained and their respective yields. The results obtained for the batch mode were: 14 g/L for the growth of biomass and an estimate of 0.22 g/g for lipid production. Likewise, for the continuous mode, its results were: 19 g/L for biomass growth and a value of 0.30 g/g in lipid production. The simulated results in continuous mode would demonstrate the effectiveness of its implementation since a more significant lipid accumulation is reached.

Dynamic Simulation of Bioethanol Production from Banana Rejected using Flocculating Yeast

Contreras, J | 2021-09-12

A dynamic model is presented to simulate a fermentation process for bioethanol production from banana rejected using a batch system. The critical model feature is using an inhibition function to relate substrate concentration and specific growth rate. Kinetic parameters were calculated based on previous experimental data, and the optimal substrate concentration is investigated. The Andrews kinetic model was adapted to the concentration profiles, indicating that it could describe the existence of substrate and product inhibition. Different initial substrate concentrations were evaluated (90-400 g/L), and simulated results suggest 200 g/L of rejected banana as a starting point to reach a high and efficient bioethanol production since a maximal ethanol production is reached with a value of 150 g/L. However, when using a higher banana, rejected concentration inhibition occurs, and therefore bioethanol production decreases to reach levels lower than 100 g/L. Based on results found, kinetic models allow obtaining important observations on microbial metabolic processes and facilitating a good approximation for further large-scale stages.

Dynamic Modeling of Tannase Production from Bacillus cereus: A Framework Simulation based on Fed Batch Strategy

Gelves Gelves, Elizabeth | 2021-09-12

Tannase enzyme is a metabolite of great interest in the industry. Typical examples of its use can be found in wines and beer production, beverage and juice fruits clarification and leather production. However, tannase production on an industrial scale is limited to the operation batch mode. For this reason, its production is low and severe limitations take the place of being carried on a large scale. To improve production, this research proposes an operation strategy based on Fed-batch mode. The kinetic constants were taken from the literature to simulate trends obtained through a Feed-batch mode of operation. One of the most important findings of this research focuses on increasing tannase production with found values of 0.380 U/g. The latter indicates that tannase production could be almost twice the concentration obtained with the traditional batch mode (0.1900 U/g). Results obtained in this research may be promising for the enzyme production industry. Using computational techniques, it is possible to identify an improvement without investing in excessive experimentation and resources.

Evaluation of the Light/Dark Cycle and Concentration of Tannery Wastewater in the Production of Biomass and Metabolites of Industrial Interest from Microalgae and Cyanobacteria

Urbina-Suarez, Nestor Andres | 2022-01-25

The tanning industry transforms animal skins into leather and produces liquid effluents with a high organic and inorganic pollutant load. This work evaluated the effect of the tannery wastewater (TWW) concentration and the light/dark cycle on the production of biomass, carbohydrates, proteins, lipids, and pigments (carotenoids and phycobiliproteins) on two microalgae (Chlorella sp. and Scenedesmus sp.) and one cyanobacterium (Hapalosiphon sp.). A non-factorial central experimental design with a response surface was implemented using the STATISTICA 7.0 software. High removal percentages for nitrates (97%), phosphates (73.3%), and chemical oxygen demand (93.2%) were achieved with the three strains. The results also highlight that the use of a constant light regime (24:0) and the concentration of real TWW affect the biomass production, since the highest concentration of biomass recorded was 1.31 g L−1 of Hapalosiphon sp. with 100% undiluted wastewater.

Cellulase Production from Trichoderma harzianum: a Framework Modeling for Evaluating Different Operating Mode Strategies

Mora, D | 2021-09-12

The cellulase enzyme has been used in essential applications in the textile industry and the formulation of some medicines. Therefore, a mathematical model based on previous reports is proposed for cellulase enzyme enhancement. First, the kinetic constants were taken from the literature. Then, two operating strategies were carried out to maximize cellulase production using 10g/L of cellulose and 0.4g/L of cells as a first strategy using a batch mode. Alternatively, a second operating mode is simulated using continuous cellulose feeding. Finally, a comparative analysis was made for determining the best operating mode related to maximal cellulase production. Interestingly, the continuous mode shows a high cellulase concentration lasting a shorter time than the batch mode to avoid inhibiting enzyme production. One of the most important findings of this work focuses on increasing cellulase production with values of 1800 FPT/L simulating the continuous mode. The latter suggests that cellulase production could be double the concentration obtained with the traditional batch mode (800FPU/L). Results obtained in this research may be promising for the enzyme production industry. Using simulation techniques, it is possible to determine an enhancement without requiring excessive experimentation and resources.

Computer-Aided Evaluation of Ethanol Production from a Continuous Operating Mode using Simulink

Alvarado, K | 2021-09-10

Fossil fuels have become a great energy source worldwide. However, its prolonged use has caused severe environmental pollution problems. Biofuels generated from biomass as a product of microbial biotechnology emerge as an alternative to the use of compounds derived from oil. Therefore, their production results in complex experiments and source investment. That is why engineering studies implementation using mathematical models and simulation techniques should be specified in bioprocesses. The latter focused on optimizing the process parameters, maximizing productivity, generating greater profitability, and reducing cost. This research aimed at the computer-assisted evaluation of obtaining bioethanol from Saccharomyces cerevisiae to determine the most critical factors in the production process using a continuous mode. It was determined that the feed rate significantly influences the bioethanol volumetric productivity.

The Circular Economy Approach to Improving CNP Ratio in Inland Fishery Wastewater for Increasing Algal Biomass Production

García Martínez, Janet B. | 2022-02-26

In this work, the capacity of wastewater from an inland fishery system in Colombia (Norte de Santander) was tested as culture medium for Chlorella sp. and Scenedesmus sp. Due to insufficient N and P concentrations for successful algae growth, the effect of wastewater replenishment with NO3 , PO4 , and Na2CO3 or NaHCO3 as a carbon source was analyzed using a three-factor nonfactorial response surface design. The results showed that the addition of NaNO3 (0.125 g/L), K2HPO4 (0.075 g/L), KH2PO4 (0.75 g/L), and NaHCO3 (0.5 and 2 g/L for Chlorella sp. and Scenedesmus sp. respectively) significantly increased the biomass of Chlorella sp. (0.87 g/L) and Scenedesmus sp. (0.83 g/L). Although these results show that the addition of other nutrients is not necessary (Na, Mg, SO4 , Ca, etc.), it is still essential to determine the quality of the biomass produced in terms of its application as a feed supplement for fish production.

Modeling of Clavulanic Acid Production from Streptomyces clavuligerus using a Continuous Operation Mode

Ariza, L | 2021-09-12

Clavulanic acid is a β-lactam inhibitor produced by fermentation with Streptomyces clavuligerus cells, and it is usually used to prevent resistance to certain antibiotics. However, CA production is limited at the bioreactor level due to its low performance. The latter generates expensive processes and challenging to operate on a large scale. In this research, a mathematical model is proposed to simulate the clavulanic acid production from an operation strategy based on continuous mode. The preceding, to identify trends allowing to improve the productivity of the mentioned metabolite. Results are compared to the traditional operating batch mode. According to the results found, the final concentration of the β-lactam inhibitor could be increased by up to 60% regarding the simulated data in batch mode. Results obtained demonstrate the importance of computational techniques in bioprocess engineering since bioprocess simulation focuses on identifying critical operating parameters as a starting point in antibiotic production optimization.

Application of Chlorella sp. and Scenedesmus sp. in the Bioconversion of Urban Leachates into Industrially Relevant Metabolites

Ortiz Betancur, Jeimy J. | 2022-02-26

: This paper explores the ability of Chlorella sp. and Scenedesmus sp. to convert landfill leachates into usable metabolites. Different concentrations (0.5, 1, 5, and 10% v/v) of leachate coupled with an inorganic carbon source (Na2CO3 , and NaHCO3 ) were tested to improve biomass production, metabolites synthesis, and removal of NO3 and PO4 . The result shows that both strains can effectively grow in media with up to 5% (v/v) leachate, while significantly reducing the concentrations of NO3 , and PO4 (80 and 50%, respectively). The addition of NaHCO3 as a carbon source improved the final concentration of biomass, lipids, carbohydrates, and the removal of NO3 and PO4 in both strains.

Optimization of Phycobiliprotein Solubilization from a Thermotolerant Oscillatoria sp

Barajas Solano, andres F | 2022-04-24

The present study evaluated the effect of multiple variables (drying time, drying temperature, biomass/solvent ratio, glass beads/biomass ratio, extraction time, and extraction speed) in the solubilization of three different phycobiliproteins (C-PC, APC, and PE) from a thermotolerant Oscillatoria sp. The strain was grown in BG11 media (28 ◦C, light: dark cycle of 12:12 h at 100 µmol·m−2 ·s −1 , 20 days) and the experiments were conducted according to a two-level randomized factorial design with six center points (38 runs). Results show that biomass/solvent ratio, glass beads/biomass ratio, and extraction time, are the most significant variables in the extraction of all three proteins, whereas the glass beads/biomass ratio and extraction time significantly affect their purity. The optimized conditions allow a statistical increase in the concentration of C-PC, APC, and PE extracted from the biomass; however, the purity was lower in comparison with the expected value. The latter occurs due to a larger biomass/solvent ratio and longer extraction times, which enhanced the solubility of other hydrophilic metabolites (proteins and carbohydrates, etc.).

Bubble coalescence model effect on oxygen mass transfer using non-newtonian fluids

Niño, Lilibeth | 2021-08

A modified bubble coalescence model including rheological conditions and shear forces in non-Newtonian fluids is evaluated using CFD (Computational Fluid Dynamics). Euler's model, along with population balance equations, was used to simulate bubble size distribution. Simultaneously, different bubble breakage and coalescence models were evaluated to investigate mass transfer and bubble diameter. A conventional aeration stirring system (Rushton turbine, ring sparger) was used and the results were validated by determining the experimental mass transfer coefficient. A 10-liter bioreactor operated under different operating conditions commonly used for non-Newtonian rheology was used. Xanthan Gum 0.25% was used to resemble the rheological conditions developed during fungal culture. CFD results were contrasted with tested data obtained from 𝑘�𝑘�𝐿�𝐿�𝑎�𝑎� measurements at different stirring speeds using the concordance d-index. A reasonable prediction was obtained comparing the modified model Luo-New to the most used conventional models Luo-Luo and Laakkonen-Luo. Therefore, model Luo-New shows the highest d values at 400-700 rpm with values of 0.83, 0.95, 0.98 and 0.69. By contrast, the model Luo-Luo showed less inaccurate values with levels lower than 0.62 in almost all comparisons. The latter concludes numerically that the inclusion of viscosity effects and shear on a bubble coalescence model improves the degree of prediction related to oxygen transfer. The latter being a critical factor in the design and testing of stirring and aeration devices.

Enhancement of Metabolite Production in High-Altitude Microalgal Strains by Optimized C/N/P Ratio

Suárez Quintana, William H. | 2022-07-04

: This study evaluated the role of C/N/P in the increase in the synthesis of carbohydrates, proteins, and lipids in two high-mountain strains of algae (Chlorella sp. UFPS019 and Desmodesmus sp. UFPS021). Three carbon sources (sodium acetate, sodium carbonate, and sodium bicarbonate), and the sources of nitrogen (NaNO3 ) and phosphate (KH2PO4 and K2HPO4 ) were analyzed using a surface response (3 factors, 2 levels). In Chlorella sp. UFPS019, the optimal conditions to enhance the synthesis of carbohydrates were high sodium carbonate content (3.53 g/L), high KH2PO4 and K2HPO4 content (0.06 and 0.14 g/L, respectively), and medium-high NaNO3 (0.1875 g/L). In the case of lipids, a high concentration of sodium acetate (1.19 g/L) coupled with high KH2PO4 and K2HPO4 content (0.056 and 0.131 g/L, respectively) and a low concentration of NaNO3 (0.075 g/L) drastically induced the synthesis of lipids. In the case of Desmodesmus sp. UFPS021, the protein content was increased using high sodium acetate (2 g/L), high KH2PO4 and K2HPO4 content (0.056 and 0.131 g/L, respectively), and high NaNO3 concentration (0.25 g/L). These results demonstrate that the correct adjustment of the C/N/P ratio can enhance the capacity of high-mountain strains of algae to produce high concentrations of carbohydrates, proteins, and lipids.

Kinetic modeling of biosurfactant production from crude oil using Bacillus subtilis cells

Alvarado, Kelly | 2022-06-23

Crude oil and its derivatives have high application in different industries, and unforeseen spills or overexploitation generate a significant threat in ecosystems, causing negative impacts on soil, water, and air. There are microorganisms capable of metabolizing hydrocarbons through the bioremediation process with biosurfactant production, but large-scale culturing and technification are still a significant challenge due to their high costs and optimization stage requirement. An unstructured kinetic model provides crucial information regarding improvements and process optimization at the first stages. Thereof prediction of bioprocess kinetic behavior is expected from mathematical expressions. Considering the above, biosurfactants’ bioprocess modeling tends to be an essential tool to increasingly focus on the efficiency and profitability of oil industries. That is why biosurfactant kinetics production from Bacillus subtilis is investigated in this research, implementing a mathematical model. Previous studies refereed experimental data to integrate into Monod, Contois, Haldane, Moser, Powell, Tessier, Aiba-Edward, Luong, Yano-Koga, and Chen-Hashimoto equations. Therefore, a nonlinear regression parameterization procedure is applied using the Matlab Fmincon Function. The best accuracy found between experimental and simulated data was achieved using the Chen-Hashimoto kinetic model with μmax, kd and ks values of 2.3239 d− 1 , 0.3748 d− 1 and 1.1619 g/L, respectively. This research suggests that biosurfactant production occurs under anaerobic conditions where hydrolysis controls microbial growth. These research results are a promising aim related to industrial biotechnology since computational modeling is essential for process efficiency from a technical and economic perspective.

Inherent Safety Analysis and Sustainability Evaluation of a Vaccine Production Topology in North-East Colombia

González Delgado, Ángel Darío | 2022-08-12

: Influenza is a respiratory disease that may cause severe consequences to human health. Influenza caused between 99,000 and 200,000 deaths worldwide in 2019. Studies have reported the presence of this virus in Santander, Colombia, a region with a high humanitarian flow. An influenza vaccine production plant topology has been proposed previously. Nevertheless, the inherent safety and sustainably behavior of this topology is unknown. Process safety plays a crucial role in the evaluation of emerging technologies since it allows the identification of potential risks. Moreover, the current sustainability policies enforce the assessment of processes considering economic, social, and environmental aspects. For this reason, a safety and sustainability evaluation of a vaccine production topology is performed in this work. The inherent safety index (ISI) methodology was implemented to analyze the process. The sustainability evaluation was performed using the sustainability weighted return on investment metric (SWROIM), in which return on investment (ROI), output potential environmental impact (PEI output), total safety inherent index (ITI), and exergy efficiency were considered. The results showed that influenza vaccine production is inherently safe since the total inherent safety index was 11. The destroyed exergy was 378.69 MJ/h, the return on investment was 86%, and the SWROIM was estimated at 81%, which means slightly negative impacts on sustainability

Evaluación de residuos de papa, yuca y naranja para la producción de etanol en cultivo discontinuo utilizando Saccharomyces cerevisiae

Urbina-Suarez, Nestor Andres | 2015-01-25

El presente trabajo de investigación tuvo como objetivo producir etanol utilizando un jarabe glucosado elaborado a partir de residuos de papa, naranja y yuca, por cultivo discontinuo como una alternativa para el manejo de los residuos generados. Para cumplir con el objetivo planteado se utilizaron cepas Saccharomyces cerevisiae, una cepa nativa (LYP) y una cepa control (CTL) obtenida del Cepario de la Universidad. Posteriormente, para la elaboración de los medios de fermentación los residuos se sometieron a un tratamiento de hidrólisis química con ácido clorhídrico al 2%v, temperatura de 75°C y 8 horas, estos parámetros fueron seleccionados como resultado del análisis estadístico del diseño factorial 33 el cual encontró diferencias estadísticamente significativas (p≥0,05) en las variables evaluadas sobre la generación de azucares reductores. Finalmente, se realizaron fermentaciones de 500ml a 30°C 150rpm con base en un diseño factorial 42 para la evaluación de los sustratos fermentativos y el microorganismo fermentador, en donde se encontró que no existen diferencias significativas (p≥0,05) tanto para los sustratos como para las cepas: control (CTL) y nativa (LYP), en la producción de etanol. Sin embargo, en las interacciones entre variables si se encontraron diferencias altamente significativas (p≤0,05), la mayor producción de etanol obtenido fue de 3,15 y 2,6%v para la cepa LYP y CLT, respectivamente, cuando se emplearon los jarabes de naranja y yuca como fuente de carbono.

Inoculation of Cilantro (Coriandrum sativum L.) with Rhizobacterias in Villa del Rosario, Norte de Santander

Carrillo Becerra, Katherine | 2015-01-01

Plant growth promoting rhizobacteria (PGPR) represent an alternative biofertilization form. In this study, was evaluated PGPR inoculation in cilantro plants. Likewise, was evaluated the practice of burning rice husk in soil preparation for crop establishment. An experimental design was used in a split plot where the main plots were soil preparation with burning rice husk and without burning rice husk with prior inoculation of Trichoderma sp. The subplots correspond to treatments with simple inoculation and co-inoculation of Azotobacter RzH120 and Azospirillum RzH132 and chemical and absolute control. Once the assumptions were tested in model residuals, normality, homogeneity of variance and randomness, an analysis of variance and multiple comparison tests by Tukey's test and principal component analysis technique was performed as size reduction. According to principal component analysis, the results showed a positive effect on the growth of plants inoculated with PGPR in the two plots with burning and without burning rice husk, however, the variable yield (P≤0.05). Also, it was found that the population of bacteria in the rhizosphere culture media NFb semisolid, Ashby and King B, was not favored by the burning of rice husks on the soil. Importantly, the results were obtained with the 30% decrease in the chemical fertilizer, which can reduce the use of these chemicals.