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CFD: A New Challenge in Bioprocess Engineering

Niño, Lilibeth | 2018

Computational Fluid Dynamics (CFD) is a powerful tool based on mathematical applications for modeling transient and spatial transport modes such as mass, momentum and heat transfer in multiphase fluids. Currently, CFD has been applied for biological engineering processes. In this paper, a review of Bioprocess engineering applications in computational fluid dynamics (CFD) is presented, including important steps such as sterilization, mixing in CSTR, mass transfer and biochemical reactions applications.

Diversidad genética de Moniliophthora roreri mediante Polimorfismo de Longitud de Fragmentos Amplificados (AFLPs)

SUAREZ CONTRERAS, LILIANA YANETH | 2018-01-06

El cultivo de cacao, está afectado por el fitopatógeno Moniliophthora roreri, que causa gran pérdida en la producción en Norte de Santander. Este estudio muestra los resultados obtenidos utilizando AFLPs de M. roreri. Con el kit para sistema de análisis II, estandarizado y aplicado a 56 muestras de M. roreri, aisladas de nueve municipios. La combinación que presentó mayor número de polimorfismos fue E-ACC/ M-CAA, con 100 bandas y un número menor de alelos (6), con la combinación E-ACG/ M-CAA se obtuvieron 90 bandas y un número de alelos mayor (23), y con la combinación E-AAC/ M-CAA se presentaron 94 bandas y alelos (12). El análisis de datos se realizó según el dendrograma de similitud o distancias genéticas de Nei, obteniéndose cinco grupos con una alta variabilidad entre las muestras, del 6,5 al 58%. Al combinar la información morfológica y molecular se determinó el nivel de diversidad genética de Moniliophthora roreri.

Development of a Selective Method for Metabolites Extraction from Microalgae Biomass

Barajas Solano, andres F | 2018-02

Background: The production of biofuel and high value products from microalgae exhibits difficulties that have been widely studied to develop viable, efficient and economic methods for recovering metabolites. Objectives: This work is focused on evaluating experimental methods to obtain carbohydrates, proteins and lipids by varying process variables (solvent concentration, temperature, biomass/solvent ratio and moisture content). Methods/Analysis: Carbohydrate and proteins were extracted by acid and alkaline hydrolysis to study the effect of biomass moisture on recovery of these metabolites. Lipids were obtained using hexane and methanol-chloroform methods and its quantification was performed by gravimetric analysis. Findings: It was found that 41.96% and 49.77% of carbohydrates were recovered from C. vulgaris using biomass without thermal pretreatment by acid and alkaline hydrolysis, respectively. Regarding to lipid extraction, hexane was used as solvent for recovering 18.22% of lipids from C. vulgaris. In addition, results suggested that dehydrating biomass at 105°C reduces recovery of high value products. Novelty/Improvement: This study proposes a selective method for extracting metabolites, which enhances efficiency of recovery when is carried out under suitable conditions of biomass moisture, time and solvent volume.

Cultivation of Chlorella vulgaris in Aquaculture Wastewater for Protein Production

Blanco, Estefany | 2018-02-02

Microalgae have emerged as environment friendly alternative source of valuable products for energy, pharmaceutical and cosmetic industries. These microorganisms have been also studied in wastewater treatments due to its ability to remove CO2, nitrogen, phosphorus, and toxic metals. In this work, cultivation of microalgae Chlorella vulgaris was carried out in aquaculture wastewater in order to reduce its contents of NO3 and PO4. In addition, different concentration of inorganic carbon sources (NaHCO3 and Na2CO3) and addition times were considered for determining suitable conditions in microalgae culture to produce proteins. It was found that highest protein content (45 % w/w) was achieved at 3.4 g/L of NaHCO3 and 19 h of addition time.

Activación de las Isoformas del Gen pr1 de Metarhizium anisopliae Durante la Patogénesis en Diaphorina citri

López Barrera, German Luciano | 2018-03-01

Se analizó la activación de las isoformas Pr1A, Pr1B, Pr1C, PR1D, PR1E, Pr1F, Pr1G, Pr1H, Pr1I, Pr1J, Pr1K del gen pr1 de Metarhizium anisopliae (Metschnikoff) Sorokin (Hypocreales: Clavicipitaceae) durante el proceso patogénico en adultos del psílido asiático de los cítricos Diaphorina citri Kuwayama (Hemiptera: Psyllidae). Se seleccionaron las cepas Ma57 y Ma62 por su alta y baja patogenicidad hacia D. citri, respectivamente. Los insectos se infectaron con una suspensión de conidias y se mantuvieron en ramas de Murraya paniculata (L.) Jack (Sapindales: Rutaceae) durante 7 días. La actividad de las once isoformas durante el proceso patogénico se detectó mediante RT-PCR en diez tiempos diferentes después de la infección. Los resultados indicaron que las isoformas Pr1A, Pr1B, Pr1C, Pr1E, y Pr1I no se activaron en ninguno de los tiempos analizados en ambas cepas. Las isoformas Pr1F y Pr1G en ambas cepas estuvieron activas desde las 0 h hasta las 168 h. Las isoformas Pr1D, Pr1H, Pr1J, y Pr1K se activaron en patrones diferentes y algunas de manera intermitente. Se observaron diferencias en los patrones de activación de las isoformas Pr1D, Pr1J, y Pr1K de la cepa 57 con respecto a la cepa 62. Las ocho isoformas restantes presentaron un patrón de activación similar en ambas cepas. Estos resultados indican que algunas isoformas probablemente se activan con el proceso de infección, otras están activas independientemente del proceso de infección y otras posiblemente tienen alguna participación en otros procesos diferentes. Nuestros resultados coadyuvan al conocimiento de la participación del gen pr1 de M. anisopliae durante el proceso patogénico en el psílido asiático de los cítricos. Se requieren más estudios para definir el papel preponderante de las isoformas del gen pr1 en la patogenicidad de M. anisopliae y su actividad eficiente en el control de plagas.

Effect of Flocculation Technology on Lipids, Carbohydrates and Proteins and Extraction from Chlorella vulgaris

Sanguino, Paola Andrea | 2018-03-03

Nowadays, Chlorella vulgaris has emerged as an attractive source of metabolites such as lipids, proteins and carbohydrates, which are widely applied to obtain high value products. This work is focused on evaluating the effect of flocculation on metabolites recovery from Chlorella vulgaris microalgae biomass. Carbohydrates were extracted through acid and alkaline hydrolysis in order to identify the efficiency of these treatments for cell wall disruption. Protein quantification was carried out under alkaline conditions and lipids were recovered by solvent extraction with hexane. It was found that carbohydrate recovery was higher using centrifuged biomass (40.55%) than flocculated biomass (24.31%) by acid treatment, while alkaline treatment exhibited yield of 20.37% and 13.19%, respectively. In addition, efficiency of 53.75% and 32.27% in protein recovery was obtained from both centrifuged and flocculated biomass. The highest lipid extraction yield (54.2%) was achieved using acid hydrolysis and hexane solvent route when centrifuged biomass was used as metabolite source. These results suggested that flocculation affect significantly the efficiency of metabolites extraction.

Improvement of Biorefinery Efficiency for Microalgae Nannochloropsis sp. via Harvesting Technology Evaluation

Sanguino, Paola Andrea | 2018-04-04

Recently, microalgal biomass has attached much attention due to the wide diversity of compounds synthesized from different metabolic pathways. This work attempts to study metabolites recovery from Nannochloropsis sp. biomass concentrated by centrifugation and flocculation. Carbohydrates were obtained using acid and alkaline hydrolysis required for cell disruption. Protein extraction was performed after alkaline pretreatment and lipids were recovery by acid hydrolysis- Soxhlet and alkaline hydrolysis- Soxhlet extraction routes. It was found that carbohydrates were recovered by acid hydrolysis in 41 % and 35.39 % for centrifuged and flocculated biomass, respectively, values higher than thus reported using alkaline hydrolysis. For protein extraction, centrifuged biomass exhibited higher recovery yield (55.48%) than flocculated biomass (38.40%). The lipid extraction route that achieved highest yield (43.45%) was acid hydrolysis with HCl followed by Soxhlet extraction with hexane. In addition, statistical analysis by T test suggested that flocculants affect negatively biomass culture, hence, efficiency of metabolites extraction.

The Effect of Temperature and Enzyme Concentration in the Transesterification Process of Synthetic Microalgae Oil

Rangel-Basto, Yeily Adriana | 2018-05

Throughout the world, the fossil fuel has supplied around the 80% of the energetic requirements, in Colombia alone 95.1% of energetic demand is made by the transportation sector solely, supplied by oil, kerosene, gasoline and diesel, this sector has an extremely small participation with biofuel of 3%, which is represented only by biodiesel. Microalgae had been proposed as biofactories with a remarkable third generation biofuels production. The culture of the microorganism comprehends interesting characteristics as countless environments where its natural growth could be replicated in fresh, salty and even sewage waters, with a higher growth rate and a higher oil production. The implementation of enzymes in the transesterification process have generated a good curiosity in the field, due to its mild reactions conditions, lesser energetic requirements, a high standard in the selection of the enzymes with the objective of avoiding the formation of soaps, creating in this way cleaner products and sub-products, in which the separation of the phases biodiesel/glycerol, give the possibility to recuperate the bio catalyzer and high output of reactions. However, the high volume of medium required to obtain lipids is one of the major drawbacks to test the viability of these enzymes. The present study aims to design an enzymatic transesterification process for the production of biodiesel form synthetic Chlorella oil. The synthetic oil was designed according to the lipid profile of C 16:0, C16:1, C18:0, C18:1, C18:2 and C18:3 from Chlorella spp CHL2 cultured on Bold Basal media under limited concentrations of NaNO3. The enzymatic transesterification efficiency was evaluated by the implementation of a 22 experimental factorial design (temperature and lipase concentration) under a 3: 1 molar ratio of alcohol:oil and a fixed reaction time of 6 hours. The obtained results show that, in order to obtain superior yields of biodiesel (>91%) the transesterification process must be carried out under temperature conditions close to 38°C and lipase concentrations of 5%.

Production of Chlorella vulgaris Biomass on UV‐treated Wastewater as an Alternative for Environmental Sustainability on High‐Mountain Fisheries

Guiza, Luisa | 2018-05

The sustained expansion of agricultural industry in Colombian high-mountain has led to an increased size of residues, especially untreated wastewater. This untreated water is an urgent matter for public and environmental health, not only by its nutrient concentration (composed especially of food residuals and feces) but also the presence of pathogens (virus, bacteria, etc.) which are discharged to the environment. The overall objective of this work is to evaluate the effect of UV-treated wastewater from a high-mountain fishery as culture media for the production of Chlorella vulgaris as a sustainable method for nutrient and water recirculation on the fishery production system. The UV-canal efficiency was evaluated by the implementation of an experimental factorial design (time, distance of the UV-lamps towards the canal, number of UV-lamps and the sample concentration) using STATISTICA 7.0 software. Results shown that time (3 to 5 minutes) and the number of lamps (3-4) of 15 Watts eliminate completely coliforms from the samples. After UV-treatment the resulting water was test as culture media for C. vulgaris production by the adjustment of C/N ratio (Sodium Carbonate/potassium nitrate) by the implementation of an experimental 23 factorial design. Results shown that higher nitrate concentrations (>0,22 g/L) and moderate carbonate concentrations (1 g/L) increase the final biomass concentration up to 4g/L in 20 days.

Design of an Electroflotation System for the Concentration and Harvesting of Freshwater Microalgae

Barajas Solano, andres F | 2018-05

Microalgae are considered as one of the most promising alternatives for the integrated use of agro-industrial water residues and the production of metabolites of high industrial interest. This is due to algae can grow on wastewater which in turn can reduce the emission of nutrients to rivers and lakes. However, the greatest scientific-technological barrier is the concentration and separation of the biomass produced. There are several processes used at different levels (from laboratory to industrial scale) such as flocculation, centrifugation, flotation, etc. These can be very expensive or can (possibly) contaminate the biomass. Unlike the previous ones, electroflotation has been proposed as a cost-efficient method, nevertheless its final efficiency will depend heavily on the type of alga and culture medium. Taking into account the above, the present project aims to design an electroflotation system for the concentration and harvest of microalgae biomass. The effect of several factors (pH, time, voltage and distance between the electrodes) and for types of materials (Copper, Aluminium, Iron and Steel) on biomass recovery efficiency from a culture of Chlorella vulgaris UTEX 1803 was evaluated by the implementation of a Design of experiments (43 non-factorial design) using STATISTICA 7.0. Results show that, the materials with higher concentration efficiency were cooper and aluminium with 40 and 80% respectively, and the most relevant factors were distance between electrodes (1-2 cm), time (>20 min) and Voltage (>15V). In order to increase the efficiency of the overall process a new 43 experimental factorial design was proposed using as factors distance between electrodes, time, voltage and agitation. Results show that agitation positively affects the total efficiency until reaching a total concentration of the biomass (100%). It was found that a voltage close to 50V and a time greater than 25 min positively affect the final efficiency of the copper and aluminium electrodes, however aluminium has the highest efficiency (> 95%) compared to copper (<85%).

Influencia del clima, uso del suelo y profundidad sobre el contenido de carbono orgánico en dos pisos altitudinales andinos del departamento Norte de Santander, Colombia

Valenzuela Balcázar, Ibonne Geaneth | 2018-05-02

El incremento y estabilización del carbono orgánico del suelo (COS) representa una alternativa viable para la mitigación del efecto invernadero. Pero el COS es severamente afectado por los cambios del suelo, existiendo controversias sobre cuáles tipos de uso de la tierra favorecen el secuestro de carbono. El clima tiene efecto importante sobre la dinámica del COS, por tanto el efecto generado por el uso y manejo del suelo es distinto en climas fríos y cálidos. Para entender como los factores clima, uso del suelo y profundidad del suelo, afectan la dinámica del COS en dos lugares del departamento de Norte de Santander en Colombia, se evaluaron propiedades físicas (arenas, limos y arcillas, densidad aparente) y propiedades químicas (pH, conductividad eléctrica, capacidad de intercambio catiónico y saturación de bases). Se determinó el contenido de carbono orgánico total (COT), fracción ligera (CO de FL), fracción húmica (CO de FH) y biomasa microbiana (CO de BM). Estas evaluaciones se realizaron en dos climas contrastantes (frío y cálido), tres tipos de uso del suelo (bosque, pasturas y cultivo intensivo) y tres profundidades (0 a 5 cm, 5 a 10 cm y 10 a 20 cm). Se encontró que hay mayor carbono orgánico en todos los compartimientos (COT, CO de BM, CO de FL y CO de FH) del suelo en clima frío. Los usos del suelo en bosque y pastura, son más favorables para el almacenamiento de COS en clima frío, mientras en cultivo intensivo genera menor contenido de COT, CO de FL y CO de BM. El índice de humificación y el CO de FH fueron mayores en cultivo intensivo de clima cálido.

Efecto de la colchicina sobre la morfología foliar y los estomas de Kalanchoe daigremontiana Raym.-Hamet & H.Perrier(Crassulaceae)

SALAZAR MERCADO, SEIR ANTONIO | 2018-05-02

El presente estudio evaluó el efecto de diferentes concentraciones y tiempo de exposición de colchicina, sobre la morfología foliar y los estomas de Kalanchoe daigremontiana. Inicialmente, se recolectaron y se sometieron las plántulas de K. daigremontiana a concentraciones de 0,025% y 0,1% (p/v) de colchicina y a dos tiempos de exposición (24 y 48 horas). Posteriormente, se realizaron estudios morfológicos como la altura de la planta (AP), anchura de la hoja (AH), número de hojas (NH), longitud foliar (LH), espesor de hoja (EH) y volumen foliar (VH) cada 15 días, durante 16 semanas después de la siembra. Luego, se caracterizaron los estomas, teniendo en cuenta el ancho, el largo, índice estomático y el número de cloroplasto por estoma. Se encontró un incremento significativo en la morfología foliar y estomática, en los tratamientos con colchicina de 0,025% a 24 y 48 horas. Lo que demuestra que el uso de la colchicina logra un mayor crecimiento en poco tiempo y aumento de la biomasa en la planta medicinal K. daigremontiana.

Multiparameter analysis of activated sludge inhibition by nickel, cadmium, and cobalt

Hernandez-Martinez, Gabriel R. | 2018-06-05

Activated sludge processes are often inhibited by nickel, cadmium, and cobalt. The inhibitory effect of these heavy metals on a synthetic wastewater treatment process was tested through pulse microrespirometry; i.e., pulse of substrate injected in a microreactor system. The inhibitory effect was tested under different conditions including the heavy metals, substrate and biomass concentrations, and exposure time. The inhibitory effect was quantified by the percentage of inhibition, half saturation constant (KS), inhibition constant (KI), and maximum oxygen uptake rate (OURmax). The results indicated that, in a range of concentration from 0 to 40 mg L−1, the three heavy metals exerted an uncompetitive and incomplete inhibitory effect, with a maximum inhibition of 67, 57, and 53% for Ni, Co, and Cd, respectively. An increase of the biomass concentration by 620% resulted in a decrease of the inhibition by 47 and 69% for Co and Cd, respectively, while no effect was observed on Ni inhibition. An increase of the substrate concentration by 87% resulted in an increase of the inhibition by 24, 70, and 47% for Ni, Co and Cd, respectively. In the case of nickel and cadmium, an increase in the exposure time to the heavy metals also increased the inhibition.

Evaluation of the effect of flocculation on harvesting of microalgaenannochloropsis SP

ZUORRO, Antonio | 2018-08

Microalgae have recently emerged as an attractive source of products for the food, energy and pharmaceutical industries due to their high biomass productivity, metabolic versatility and environmental sustainability. This work focuses on the effect of flocculation on the harvesting of microalgae Nannochloropsissp. Through a three-factor experimental design. The most suitable conditions for flocculation were determined based on flocculant (AlCl3) dosage, pH and culture time. In addition, flocculant adding-pH adjustment methods were studied and harvesting was performed according to the method that provided the best results. The pH adjustment after flocculant addition showed higher flocculation efficiency (above 90%) compared to the reverse process. It was also found that the microalgae cells exhibited spontaneous sedimentation, suggesting that the use of flocculant is not required for biomass collection.

A modified spin filter for overcoming of gas liquid mass transfer problems in a stirred tank bioreactor

Niño, Lilibeth | 2018-08-30

Technical-economic Prefeasibility Study of Astaxanthin Production System from H. pluvial Microalgae in Colombia

González-Delgado, Angel Darío | 2018-09

Nowadays, microalgae has been considered as source of valuable products such as astaxanthin, which is a carotenoid with great commercial potential as antioxidant widely used in many industries such as pharmaceutical, cosmetics and health supplement. Objectives: This work was focused on technical-economic pre-feasibility study of hybrid system for cultivation, harvesting and extraction of astaxanthin from H. pluvialis microalgae in five Colombian cities (Barranquilla, Cartagena, Santa Marta, Barrancabermeja and Cúcuta). Methods/Analysis: A hybrid system was purposed based on flat panel + open pond Photo Bioreactor (PBR), in which cell growth is inhibited by increasing radiation. Additional stages as centrifugation, filtration, and drying, milling and supercritical extraction were also implemented. An economic prefeasibility study was applied in order to determine the suitability of locations in terms of NPV, IRR and PP. Findings: It was found that the most feasible location for astaxanthin production is Santa Marta with NPV, IRR and PP of € 5,529,203, 50% and 1.9 years, respectively. Novelty/Improvement: These results suggested that astaxanthin can satisfy national demand of antioxidants by producing it from H. pluvialis microalgae.

Analysis of the biodiesel production yield from waste frying oil

Urbina-Suarez, Nestor Andres | 2018-09

This research sought to produce biodiesel from waste frying oil (WFO) from chicken grills by using chemical transesterification to evaluate quality conditions and the yield of the biodiesel obtained. For this, acid esterification and basic transesterification were applied under the following conditions: reaction temperature 60°𝐶, catalyst concentration of 1% (m/m) KOH, oil:alcohol 1: 6 𝑚𝑜𝑙𝑎𝑟 𝑟𝑎𝑡𝑖𝑜, and two reaction times (55 𝑎𝑛𝑑 70𝑚𝑖𝑛) for the transesterification. The physicochemical properties of the raw material were analyzed (i.e., density, humidity, kinematic viscosity, fatty acid profile, acidity index, peroxides, and saponification) where the WFO showed high contents of oleic acid (42.45%) and palmitic acid (33.52%), which are fundamental for biodiesel production. Chemical transesterification under the conditions of 60°𝐶, 1% KOH, and 70𝑚𝑖𝑛 obtained the best yield by presenting a high conversion percentage (96.15%) and an acid number of 1.33𝑚𝑚𝐾𝑂𝐻/𝑔, according to ASTM D6751 and EN 14214 international standards.

Non-Newtonian Behavior Effect on Gas-liquid Mass Transfer using an Anchor Impeller for CSTR Bioreactors: A CFD Approach

Niño, Lilibeth | 2018-11

Objectives: kL a mass transfer coefficient was predicted using CFD (computational fluid dynamics) for analyzing non-newtonian effects on gas liquid mass transfer in a 10 L bioreactor stirred with an Anchor Impeller. Methods/Statistical Analysis: The set up bioreactor configurations were defined by typical culturing conditions used for fungi organism. Bubble breakage frequency and coalescence rate were simulated using Luo - Colaloglou and Tavlarides models and PBM approaches, respectively. Simulated results from different shear rates due to non-newtonian behaviour are compared by analyzing its influences in bubble size and power input. Findings: A clear relationship between high levels of shear rates and small bubble sizes is found in this work. The later is also associated with the high values of kL a simulated (270 h-1) and compared to levels found at low shear rates (62 h-1). Application/Improvements: Impressed by these findings new design optimizations for non-newtonian bioprocessing applications would be improved using CFD.

Evaluación de la capacidad antifúngica de los extractos etanólicos depropóleoante la antracnosis en tomate de árbol (Solanum betaceum Cav.)

CAMPO VERA, YESENIA | 2018-12-19

La antracnosis es una enfermedad fúngica que tienen una importante incidencia en los cultivos de tomate de árbol. La misma es ocasionada por los fitopatógenos Colletotrichum gloeosporioides (Penz.) o su teleomorfo Glomerella cingulata (Stoneman). La presente investigación evaluó la capacidad antifúngica del propóleo, un derivado de los productos apícolas, obtenido en tres localidades diferentes de Norte Santander (Oripaya, San Cayetano, Los Patios). Inicialmente, se realizó una caracterización de la resina mediante la identificación de sus propiedades fisicoquímicas, tales como: cenizas 3,56±0,64%; humedad 5,11±0,11%;material insoluble 5,11±0,11%; índice de oxidación 49± 1%; puntos de fusión 80,90±3,21; espectro de absorción UV en el rango de 270 a 350 nm tales como: cenizas, humedad, material insoluble, índice de oxidación, puntos de fusión, espectro de absorción UV y posteriormente, se verificó el porcentaje de inhibición de los microorganismos empleando la técnica de antibiograma con sensidiscos impregnados con tres concentraciones de extracto etanólico de propóleo EEP (10%, 20%, 30%). Se encontró que los propóleos cumplen con los estándares internacionales para los parámetros de cenizas, humedad, puntos de fusión y espectros de absorción de la radiación ultra violeta (UV), evidenciándose la calidad del propóleo y la presencia de flavonoides, además del mismo se halló que el propóleo de la localidad de Oripaya al 10% tiene mayor capacidad de inhibición frente a C. gloeosporioides (Penz.).

Physicochemical study of used frying oil as feedstock for the production of biodiesel

Acevedo Páez, J C | 2019

A diagnosis was made of the availability and quality of the used frying oil of the establishments dedicated to chicken fry in the city of San José de Cúcuta, to evaluate its technical feasibility as a feedstock in the biodiesel production. A survey was applied to 21 restaurants, evidencing that they reuse the oil less times when having a high monthly consumption (i.e. more than 80 liters, contrary to those consuming less than 60 liters, which reuse the oil more than 3 times. As a final disposition, 86% of establishments sell the used frying oil at $750/liter and 14% deliver it to be used by external persons. The physicochemical properties of used frying oil were analyzed as: fatty acid profile, density, moisture content, refractive index, acidity index, peroxide index and saponification index. The used frying oil presented high content of oleic acid (42.45%) and palmitic acid (33.52%), converting it into a potential feedstock by presenting fatty acids characteristics from palm oil, which is the main source for the production of biodiesel in Colombia. To improve the organoleptic characteristics of the used frying oil (dark colour, strong odour, emulsions), it was subjected to heating and filtering to remove the particles that affect the yield of biodiesel production.