Ciencias Exactas y Ciencias de la Salud
Permanent URI for this collectionhttps://hdl.handle.net/11285/551039
Pertenecen a esta colección Tesis y Trabajos de grado de las Maestrías correspondientes a las Escuelas de Ingeniería y Ciencias así como a Medicina y Ciencias de la Salud.
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- Effect of SOx from simulated flue gas on growth and gene expression of S-compounds in the microalgae Desmodesmus abundans(Instituto Tecnológico y de Estudios Superiores de Monterrey, 2024-11-11) Hernández Barrientos, Bryan Zeth; Pacheco Moscoa, Adriana; emimmayorquin; Mora Godinez, Shirley María; School of Engineering and Sciences; Campus MonterreyDesmodesmus abundans high CO2 acclimated strain (HCA) is a microalga adapted for 13 years to high CO2 atmospheres. Previous studies have shown overexpression of genes associated with purines and folate biosynthesis under model flue gas (250 000 ppm CO2, 700 ppm NO, and 100 ppm SO2). Therefore, it is hypothesized that a high S concentration in the growth medium generates biomass with desirable concentrations of S-containing compounds reflected in the overexpression of key genes involved in the biosynthesis of purines and folate, and other associated pathways such as cysteine, methionine, and S metabolism. D. abundans was cultured with different S concentrations in Erlenmeyer flasks to ¾ log phase (4 d) under 25% v/v CO2/air (continuous flow at 0.05 vvm), 300 mL BG11 medium, 25 ± 2 °C, 100 rpm, and 85 µmol PAR-photons m-2 s-1 of continuous light). Three experimental conditions in triplicate, and duplicated biologically, were tested: i) low S (BG11-3/4S, 7 mg L-1 SO42-), ii) high S (BG11-S+SOx, 100 ppm SO2 continuous supply), and iii) control (BG11, 29.2 mg L-1 SO42-). Gene expression analysis of pathways of interest was done using RNA-Seq. Analysis of differential expression of genes (DEGs) compared S treatments to the control (|Log2FC > 1| padj < 0.05). DEGs were obtained using CDS information of D. abundans HCA and filtered genes were mapped against KEGG pathways. Also, free amino acids were analyzed using a Waters ACQUITY UPLC® System with a fluorescence detector. Neither culture was inhibited by the growth condition (no lag phase) and exponential growth was similar among cultures; however, final biomass production was highest in the control (0.8 ± 0.1 g L-1 d.w.), followed by the high S and low S conditions (0.6 ± 0.06 and 0.51 ± 0.06 g L-1 d.w. respectively). Therefore, the presence of SOx slightly reduced by 19% final biomass production. A similar trend was observed for total protein content with a greater reduction of 38% under high S (56.2 ± 1.6%, 34.6 ± 0.41%, and 26.5 ± 3.7% d.w. for the control, high S, and limited S, respectively). DEGs showed that S-limitation resulted in up-regulation of sulfate assimilation- related genes but did not correlate to a greater quantity of S-containing amino acids and only the serine O-acetyltransferase (SAT) gene was upregulated in the cysteine and methionine pathways under this condition. Although upregulation in the folate biosynthesis pathway could be observed in both conditions, these genes were not related to the interconversion of folate derivatives. Given that gene expression of reactions of interest was not clearly observed through transcriptomic analysis, neither synthesis of S-containing amino acids, implementation of direct approaches based on sequence homology of specific genes and quantification of other S related compounds as folate should be pursue.
- Electrified tribological study of bio-derived lubricants for electromobility applications(Instituto Tecnológico y de Estudios Superiores de Monterrey, 2024-11-03) Rubio Hernández, Carlos Cristóbal; Farfán Cabrera, Leonardo Israel; emipsanchez; Reséndiz Calderón, César David; Vázquez Lepe, Elisa Virginia; School of Engineering and Sciences; Campus Ciudad de México; Hernández Peña, AndysClimate change has forced humanity to develop less harmful alternatives to the environment. Electromobility has then increased in popularity, aiming for humankind's greener and climate-neutral future. Nevertheless, the complete change in the vehicles’ driveline caused different complexities, including tribological problems; therefore, new lubricants should fulfill the requirements needed in the XXI century’s transportation. Moreover, stray currents and induced voltage are inevitable. Hence, new lubricants must have good electric properties that do not hinder their lubricity capability due to these harsher conditions. In addition, conventional lubricants and their additives harm the environment and human health during production, usage, and disposal. A considerable amount of used lubricants end up polluting different ecosystems and potentially affecting biodiversity and health. If the power source of vehicles is becoming greener, so should their components, and the lubricants are not an exception. Bio-based lubricants come from renewable resources, are biodegradable, and are less toxic to the environment and human interaction. Nevertheless, not all bio-lubricants can be considered sustainable since they could give rise to a conflict, economic and ethical, with food production. This research evaluates the performance of two non-edible bio-based lubricants, neat Jatropha curcas, and Micro-algae oils, and used them as additives of Mineral Group II and synthetic PAO 4 oils, respectively, at low volumetric concentrations of 5 and 10%, by characterizing their physicochemical properties and assessing their tribological performance in a four-ball tester, which was modified to run electrified trials to emulate the conditions in which they would operate in an electric vehicle’s powertrain.
- Reduction of chemical oxygen demand of nejayote and production of potentially bioactive polysaccharides after fermentation with alkaline microalgae-cyanobacteria consortium(Instituto Tecnológico y de Estudios Superiores de Monterrey, 2022-06-14) Del valle Real, Marinat; Gutiérrez Uribe, Janet Alejandra; 274602; Gutiérrez Uribe, Janet Alejandra; puemcuervo; Luna Vital, Diego Armando; School of Engineering and Sciences; Campus Puebla; Franco Morgado, MarianaAlkaline wastewater from maize lime-cooking, commonly known in Mexico as nejayote, contains a significant amount of soluble solids and a chemical oxygen demand (COD) higher than 11,400 ± 141 mg O2 L-1. After a sedimentation process, supernatants of this effluent were fermented for 15 days with an alkaliphilic microalgae-cyanobacteria consortium (AMC). The project was divided in two parts: a laboratory scale and pilot scale. At laboratory scale, flasks of 1000 mL were used to growth AMC in mineral salt medium (MSM) used as control (M) and inoculum. Nejayote was obtained from a local tortilla bakery and sterilized (NE and N) to compare the effect of endogenous microorganisms besides AMC in the production of byproducts after their fermentation. In addition, nejayote was used as a blank without AMC (NB). For pilot scale a 100 L High-Rate Algal Pond (HRAP) photobioreactor was used where AMC was grown with MSM (MSM-HRAP), nejayote was used to grow AMC (N-HRAP) and nejayote was used as a blank (NB-HRAP). At laboratory scale M produced higher AMC biomass, reaching 228%, than N, NE, or NB, which reached 35%, 26% and 28%, respectively. After 15 days, a pH reduction was observed in N fermentation going from 9.5 to 8.76 in contrast to the increase from 9 to 10 in M. NE showed the best COD removal, reaching more than 50% efficiency after 12 days of fermentation. For pilot scale NB-HRAP produced the highest biomass concentration reaching 300% after 7 days. None of the fermentations showed a significant COD removal since organic matter such as carbohydrates increased. Significant differences were observed in the polysaccharides and protein content of the biomass recovered from control (M) compared with the fermentation process using nejayote as a culture media. Particularly, NB had the highest intracellular protein (ICP) content with a 24% ± 2% DW, followed by NE with 19% ± 0.4% and N with 16% ± 1%. Moreover, an increase of extracellular polysaccharides (EPS) and proteins was observed during the fermentations reaching a maximum concentration of 16217 土 1910 μg mL-1 and 7475 土 2152 μg mL-1 at day 6. Further analysis of the amino acid profile, functionality, and stability of this potential single cell protein (SCP) production process should be considered to promote the use of this strategy to reduce COD and generate added value products.
- Characterization of the effect of UV-A light and agitation on the exopolysaccharide production of Chlorella vulgaris and Porphyridium cruentum(Instituto Tecnológico y de Estudios Superiores de Monterrey, 2022-05) Garza Rodríguez, Zaida Berenice; GARZA RODRIGUEZ, ZAIDA BERENICE; 838147; Benavides Lozano, Jorge Alejandro; emipsanchez; Jacobo Velázquez, Daniel Alberto; Santacruz López, Yolanda Arlette; School of Engineering and Sciences; Campus Monterrey; Hernández Pérez, JesúsMicroalgae species are photosynthetic microorganisms that are a sustainable source of bioproducts due to their ability to reduce anthropogenic carbon dioxide in the atmosphere. The number of studies focused on their biologically active molecules, such as lipids, proteins, polysaccharides, and pigments, has been increasing in the last years due to their promising application as valuable products. In this context, the exopolysaccharides (EPS) from microalgal sources stand out as high-value molecules for their potential applications in the nutraceutical and pharmaceutical industries. However, studies aimed to find strategies and optimal conditions to promote the biosynthesis of EPS are still required to make these molecules economically feasible. The effect of ultraviolet light A (UV-A) is studied on biomass and EPS productivity of the red microalgae Porphyridium cruentum and the green microalgae Chlorella vulgaris testing three levels: L0, L1 and L2. Likewise, the effect of the agitation factor on cell growth and EPS productivity are analyzed for the two microalgae species testing two levels: A0 and A1. After recovering the EPS using centrifugation and diafiltration, their potential antioxidant activity was tested using the 2,2-Diphenyl-1-prykylhydrazyl (DPPH) radical scavenging assay. The UV-A light (315-400 nm), along with photosynthetic active radiation (PAR) increased EPS productivity in both C. vulgaris and P. cruentum to 1.21-fold and 2.43-fold, respectively, compared to light control conditions (PAR at 35.6 µmol m⁻² s⁻ ¹). The highest P. cruentum EPS productivity was 8.67 mg/g DW biomass at the highest tested UV-A level and lowest agitation(L2A0), and the highest biomass concentration was 8.57 g/L at the highest agitation (A1) due to a possible improvement in nutrient distribution. For C. vulgaris, the highest productivity was 1380 mg/g DW biomass at intermediate UV-A light level (L1). The highest biomass concentration of C. vulgaris was 0.34 g/L at the highest UV-A level (L2), treatment that conversely displayed the lowest EPS productivity (73.08 mg/g DW biomass). The study of antioxidant activity revealed that EPS show DPPH radical scavenging activity. The mean highest radical scavenging effect (%) of P. cruentum and C. vulgaris EPS was 56.48 ± 4.46 and 46.31 ± 3.2 at 4 mg/mL and 2 mg/mL, respectively. This work contributes to the characterization of abiotic factors that could potentially influence the production of high-value EPS molecules that display bioactivity of interest for health applications.
- Microalgae-based livestock wastewater treatment and resource recovery: a circular bioeconomy approach(Instituto Tecnológico y de Estudios Superiores de Monterrey, 2021-12-07) López Sánchez, Anaid; Carrillo Nieves, Danay; emijzarate; Orozco Nunnelly, Danielle A.; Senés Guerrero, Carolina; Aguilar Juárez, Óscar; Escuela de Ingeniería y Ciencias; Campus Monterrey; Gradilla Hernández, Misael SebastiánThe livestock industry is a sector of great relevance worldwide. This sector accounts for 1.4% of the world's Gross Domestic Product (GDP) and is a source of livelihood for more than 1.3 billion people. Furthermore, thirty-nine percent of the worldwide protein demand is covered by this sector. However, this activity is one of the top polluting industries, accounting for 14% of the greenhouse gasses (GHG) originated from anthropogenic sources. Additionally, the livestock sector is the largest land user on earth, using 70% of the total agricultural land and 30% of Earth’s land surface. One-third of the global cereal production is destinated for animal feed, of which some nutrients are retained by the animals and the rest is released to the environment without previous treatment, resulting in soil degradation, water and air pollution and, consequently, serious human health impacts. Circular bioeconomy (CBE) has emerged as a potential driver towards the sustainability of livestock production systems. One of the main objectives of the CBE model within the livestock industry is the minimization of the usage of raw material resources through the recycling, reuse, and revalorization of waste and wastewater. Microalgae-based wastewater treatment (MbWT) is a potential solution aligned with the CBE principles, in which the nutrients contained in the livestock wastewater (LW) are recovered and transformed into high value-added products with a wide range of industrial applications. The overall performance of MbWT (i.e., nutrient removal efficiencies and biomass production) is highly dependent on a wide range of factors, such as the microalgal strain and the composition of the wastewater. However, most of the existing studies that implemented MbWT have focused on a single LW type. Therefore, the main objective of this thesis is to treat a mixed effluent composed of the most common ADLW (from cattle, swine, and poultry), to understand the effects of the mixture of all three types of LW on cell growth and pollutant removal efficiencies of microalgal cultures (Chlorella vulgaris, Haematoccocus pluvialis and Chlamydomonas spp.). Through an evaluation of the mixture design, the optimal fraction of these different types of effluents (ADCW, ADSW, and ADPW) was analyzed to obtain maximum microalgal biomass productivity and 7 pollutant removal rates (COD, TN and TP). Furthermore, these microalgae were tested in all possible combinations of mono-, bi-, and tri-cultures. The first chapter of the present thesis consists of a thorough review of the literature to address the most significant factors affecting nutrient removal and biomass productivity in MbWT, including: (i) microbiological aspects, such as the microalgal strain used for MbWT and the interactions between microbial populations; (ii) physical parameters, such as temperature, light intensity and photoperiods; and (iii) chemical parameters, such as the C/N ratio, pH and the presence of inhibitory compounds. Additionally, different strategies to enhance nutrient removal and biomass productivity, such as acclimation, UV mutagenesis, multiple microalgae culture stages (including monocultures and multicultures) are discussed. The second chapter of this thesis presents the first study of MbWT using anaerobically digested swine, poultry and cattle wastewater (ADSW, ADPW and ADCW) mixtures. A centroid mixture design was used to determine the optimal mixture to promote higher cell concentrations and pollutant removal efficiencies of the microalgae Chlorella vulgaris, Haematococcus pluvialis and Chlamydomonas spp. cultured as mono-, bi-, and tri-cultures. Additionally, A redundancy analysis was performed to analyze the correlation between microalgal cultures and the removal efficiencies of the digestate pollutants. The results herein show that C. vulgaris as a monoculture in a digestate mixture of 0.125:0.4375:0.4375 (ADSW:ADPW:ADCW) resulted in cell growth of 3.61×107 ± 2.81x106 cell mL-1, a total nitrogen removal of 85%±2%, a total phosphorus removal of 66%±3% and a chemical oxygen demand removal of 44%±7%. The specific composition of the effluents plays a key role in microalgal performance due to their respective nitrogen and phosphorus content. Furthermore, this study suggests that a mixture of the three most common digestates generated by livestock farms offers a promising alternative for the treatment and revalorization of LW, by taking advantage of the unique composition that each digestate possesses. Further studies are warranted to gain a deeper understanding of the interspecific microalgal interactions occurring in mixed cultures that may enhance or hinder the performance of MbWT.
- Culture of Euglena gracilis in photoautotrophy for paramylon production: effect of pH and media composition(Instituto Tecnológico y de Estudios Superiores de Monterrey, 2021-11-15) Martín Roldán, María; ; Pacheco Moscoa, Adriana; puemcuervo/tolmquevedo; Senés Guerrero, Carolina; School of Engineering and Sciences; Campus Monterrey; Valledor González, LuisMicroalgae have been widely studied in biotechnology for their application in various areas such as bioremediation, production of biofuels, or use in nutrition. More specifically, certain species are recognized to produce compounds of high commercial value. Euglena is a group of microalgae characterized by the generation of the reserve polysaccharide paramylon, with promising prospects for its application in pharmacology, nutrition, to produce bioplastics, or biodiesel. Paramylon is accumulated mainly in the presence of organic carbon in the culture medium; however, this represents a challenge when establishing a large-scale culture due to the risk of biological contamination. In this study, an extensive study of the literature was carried out with respect to the autotrophic culture of Euglena gracilis destined to paramylon production. As a result, we evaluated the effect of culture pH, vitamin supplementation, and nitrogen source in the culture medium in order to reach the maximum biomass productivity. A pH of 7.5 and ammonium as nitrogen source were optimum for the autotrophic culture of E. gracilis, while an improvement in productivity was not observed with vitamin supplementation. Finally, it was possible to scale up the photoautotrophic culture of E. gracilis to a 1-L airlift photobioreactor. In conclusion, there is still much optimization work to achieve the biomass and paramylon productivity reported for the heterotrophic cultures of E. gracilis, but the results of this study reveal its viability.
- The energy use of the macroalga pelagic Sargassum in the Mexican Caribbean(Instituto Tecnológico y de Estudios Superiores de Monterrey) García Dorantes, José Gil; MEMBRILLO HERNANDEZ, JORGE; 21703; Membrillo Hernández, Jorge; puelquio, emipsanchez; Benjamín Ordóñez Díaz, José Antonio; Membrillo Hernández, Jorge; Ganem Corvera, Ricardo; Escuela de Ingeniería y Ciencias; Campus Ciudad de MéxicoThe potential of the pelagic Sargassum as feedstock for energy and substrates production is evaluated from an engineering point of view to determine if the macroalgae is a source of renewable biomass at a large-industrial level. This alternative could be a solution to mitigation and adaptation for the influx problem in the Caribbean coastline of Mexico (and other Caribbean countries). Recent research and experiments suggest that macroalgae can be processed by biorefinery systems like Hydrothermal Liquefaction (HTL) that makes suitable the use of the Pelagic Sargassum as a source of renewable energy and a substrate of potential products and services. Two different process scenarios, with or without a heat exchanger unit, are simulated in Aspen Plus to evaluate the physical, chemical, and cost feasibility of the macroalga continuous HTL to obtain bio-crude oil, an aqueous phase, gaseous phase, and char, as valuable products at an industrial production with a potential use such as biofuel, and fertilizer. Both cases are thermodynamically, energetically, and economically evaluated with a macroalga sludge feedstock of 2.79 M t/year, a total product sales of $14.94 M USD/year, and a payback period of 5.54 years in one of the scenarios considering the total capital, and utility costs of the integrated system and its boundaries. The production of 1.87 PJ/year of energy equates to 0.05% of Mexico's primary energy production from crude oil in 2019. This study stands for an opportunity for adaptation and mitigation of the problem that is affecting the Caribbean zone, as well as for an opportunity of synergy between the scientific, private, and government sectors.
