Carrera de Biotecnología

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Subject: search.filters.subject.ACTIVIDAD ANTIMICROBIANA

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Now showing 1 - 10 of 11
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    Análisis de la capacidad antimicrobiana de un péptido obtenido en un sistema de expresión Escherichia coli J53 frente a cepas de Staphylococcus spp.
    (Universidad Técnica de Ambato. Facultad de Ciencia e Ingeniería en Alimentos y Biotecnología. Carrera de Biotecnología, 2025-02) Llambo Charco, Darwin Marcelo; Garcés Moncayo, María Daniela
    Pathogenic microorganisms of the Staphylococcus spp. genius have represented one of the main causes of infections in nosocomial environments, immunosuppressed population, and patients with medical devices. The S. aureus strain has been particularly worrying due to its increasing resistance to antibiotics such as methicillin (MRSA) and certain beta-lactams such as cephalosporin and penicillin due to the presence of the mecA gene. Obtaining proteins from expression systems is a viable alternative for the development of new therapeutic avenues for infections caused by the Staphylococcus spp. genus. This research project was developed with the aim of analyzing the antimicrobial capacity of the peptide Alpha-1-Purothionine obtained in an E. coli J53 expression system against strains of S. aureus and coagulase-negative S. (CoNS). The process began with the cellular chemically competent of the host, induction with IPTG and the analysis of the expression by means of SDS PAGE, where a certain level of basal expression is evident. The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) were evaluated. Finally, it was determined that the peptide presented antimicrobial properties, inhibiting the growth and development of the S. aureus and CoNS strains through colorimetric verification using the minimum inhibitory concentration (MIC) and the minimum bactericidal concentration (MBC), showing values of 8,5 micrograms per millimeters for S. aureus and 17,0 micrograms per millimeters for CoNS.
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    Evaluación de la actividad antimicrobiana in vitro de aceites esenciales frente a microorganismos patógenos y del deterioro de alimento
    (Universidad Técnica de Ambato. Facultad de Ciencia e Ingeniería en Alimentos y Biotecnología. Carrera de Biotecnología, 2025-02) Chango Chimborazo, Yajaira Estefania; Arancibia Soria, Mirari Yosune
    Essential oils (EOs) are volatile compounds, rich in secondary metabolites such as monoterpenes and sesquiterpenes, noted for their antimicrobial activity, attributed to their hydrophobicity and high concentration of active phenols (thymol, carvacrol, and eugenol). These compounds alter the integrity of microbial membranes, increasing their permeability and generating oxidative stress. The agar diffusion method is used to categorize antimicrobial activity into four levels (+++; fully inhibited, ++; partially inhibited, +; slightly inhibited, and -; no inhibition). However, this method presented limitations due to the volatility and hydrophobicity of EOs, which affected their uniform diffusion. The in vitro evaluation of 50 EOs against 12 microorganisms revealed greater efficacy against Gram-positive bacteria due to their more permeable cell wall. Although Gram-negative bacteria are more resistant due to their complex outer membrane. EOs such as thyme and oregano were able to inhibit them thanks to their bioactive compounds. In contrast, anaerobic Clostridium perfringens showed complete resistance, likely due to their spore-forming capacity and the reduced production of reactive oxygen species (ROS) in the absence of oxygen, which limits the antimicrobial action of EOs. In fungi, thyme and cinnamon showed significant activity, while against beneficial bacteria the action was minimal. Their efficacy depends on the active compounds, oil volatility, and experimental conditions. Finally, EOs represent a sustainable and natural alternative as antimicrobial agents, aligning with the Sustainable Development Goals (SDGs). Their application in the food and pharmaceutical industries can improve food safety and meet the demand for natural preservatives in consumer products.
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    Eficiencia del almidón de chonta (Bactris gasipaes) como agente encapsulante sobre la actividad antimicrobiana de la doxiciclina
    (Universidad Técnica de Ambato. Facultad de Ciencia e Ingeniería en Alimentos y Biotecnología. Carrera de Biotecnología, 2025-02) Aponte Urrutia, Kerly Anais; López Hernández, Orestes Darío
    Doxycycline is an antibiotic of great interest in the health area, since it serves as a treatment for a variety of bacterial infections, but it has a drawback since it tends to degrade very easily at the time of its production, that is why new alternatives have been sought to preserve its bioactive components and protect it from contamination and even increase its bioavailability with the help of microencapsulation which is a technique that uses encapsulating materials such as natural polymers in order to generate greater effectiveness in encapsulation. For this, three suspensions were made with different proportions, using analysis techniques and verification of microencapsulation efficiency which were, performance analysis, statistical analysis, thermograms by means of differential scanning calorimetry (DSC) and antimicrobial evaluation, which was carried out by means of antibiograms of diffusion disks in Müller Hinton agar, to determine the inhibition of the microencapsulate against the E. coli bacteria. Through the different analyses carried out, it was obtained that the best performance and inhibition halos were given in the proportion 20:80, in addition to this, through the thermograms it was possible to observe the melting peaks where it was also represented that the best curve was that of the proportion 20:80. This is thanks to the fact that with a higher polymeric load, the percentage of microencapsulation efficiency increases. This could also be observed with the help of an-ANOVA analysis, which allowed the most significant performance to be seen through statistical graphs.
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    Determinación de la actividad antimicrobiana y antioxidante de los extractos de la planta sunfo (Clinopodium nubigenum) frente a cepas de Staphylococcus
    (Universidad Técnica de Ambato. Facultad de Ciencia e Ingeniería en Alimentos y Biotecnología. Carrera de Biotecnología, 2024-02) Chiriboga Cordones, Juan Fernando; De la Torres Olvera, Helena Maritza
    Foodsborne illnesses cause symptoms such as: diarrehea, vomiting and stomach pains; the treatment is the use of antibiotics such as: cephalosporins, penicillin and aminoglycosides. Due to the bad use, resistance has occurred to bacteria such as: E. coli, L. monocytogenes, S. aureus, among others. In the present investigation, the bacteria used was S. aureus and Coagulase Negative Staphylococcus (CoNS), obtained in cheeses from markets in the City of Ambato, where searched for an alternative to the use of antibiotics through antimicrobial tests and its relationship with the antioxidant activity. For this purpose, an extract of the Sunfo (C. nubigenum) was obtained, where its main components are polyphenols such as: flavonoids and phenolic acids. Through the Soxhlet method, secondary metabolites were obtained together with the solvent ethanol. The identification of the bacteria was realized on Salted Mannitol Agar, a yellow colour indicated the presence of S. aureus and a red colour indicated the presence of CoNS. For the antimicrobial test, the Minimum Inhibitory Concentration (MIC) and Bactericidal Concentration (MBC) were used together with the resazurin indicator, observing a change in coloration; for antioxidant activity, a colorimetric assay was realized with 2,2-diphenyl-1-picrylhydrazyl (DPPH). Finally, it was determined that the C. nubigenum extract presented antimicrobial properties, due to the inhibition of the S. aureus and CoNS species, verifying the colour change with the MIC and MBC test. Likewise, the evaluated extract presented antioxidant properties by reading absorbances between DPPH and the extract.
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    Obtención del péptido antimicrobiano aedesina por medio de un sistema de autoescisión mediado por inteina, utilizando un sistema de expresión en Escherichia coli BL21 (DE3)
    (Universidad Técnica de Ambato. Facultad de Ciencia e Ingeniería en Alimentos y Biotecnología. Carrera de Biotecnología, 2023-09) Mejía Bonilla, Dimitri Serge; García Solís, Mario Daniel
    Antibiotics have significantly improved people's lifestyle since their implementation. However, at present, the indiscriminate use of these drugs has generated a health crisis due to antimicrobial resistance. The current trend shows an increase in the number of resistant strains that cannot be treated with conventional antibiotics, which has led to the need to develop a new generation of antibiotics. One of the most promising alternatives is the application of antimicrobial peptides, among which aedesin stands out. The present research project focuses on the implementation of a purification strategy for aedesin. This strategy consists of an intein-mediated self-cleavable system, which possesses a prohibition condition that disables self-cleavage in the presence of high salt concentrations. A heterologous system of synthesis in E. coli BL21 was used for expression. In conclusion, synthesis in bacteria offers several advantages compared to other methods of obtaining peptides. Furthermore, the strategy used for the purification of aedesin has proven to be effective. However, there are still challenges to be overcome, such as peptide toxicity and basal expression. Despite these drawbacks, the successful expression and purification of aedesin position it as an interesting candidate for analysis in future clinical studies.
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    Determinación del efecto antioxidante y antimicrobiano de extractos de diferentes tipos de ortiga (Urtica dioica, Urtica urens, Urtica leptophylla, Urera baccifera) frente a cepas de Staphylococcus aureus, Escherichia coli, Listeria monocytogenes y Bacillus cereus
    (Universidad Técnica de Ambato. Facultad de Ciencia e Ingeniería en Alimentos y Biotecnología. Carrera de Biotecnología, 2023-03) Mariño Manzano, Kevin Daniel; Garcés Moncayo, María Daniela
    Medicinal plants have become a hope for the development of alternative medicines, for this reason, the WHO promotes the study of medicines based on plant sources, since they frequently generate few side effects, minimal toxicity and combat antimicrobial resistance. The Urticaceae family has a high index of bioactive molecules. This research focuses on evaluating the biological activity of hydroalcoholic (EtOH) and methanolic (MtOH) extracts from four nettle species. Initially, the extraction was carried out, which yielded variable yields, highlighting the MtOH of U. dioica corresponding to 2.487 percent as the best result. The antioxidant capacity was determined using the DPPH technique, all the extracts present considerable antioxidant activity, however, the MtOH of U. baccifera inhibited an equivalent to 435.80 micromoles of Trolox per liter. The quantification of total phenols was measured by the Folin Ciocalteu assay, which demonstrated that EtOHs exceed MtOHs. The hydroalcoholic extraction of U. dioica showed a higher amount of phenolic compounds (87,840 milligrams of gallic acid per gram). The antimicrobial activity was estimated by the microdilution method in 96-well plates based on resazurin, with which the MIC and MBC were determined. The extracts that inhibited at a lower concentration were: MtOH from U. baccifera and U. urens to E. coli and B.cereus, EtOH from U. urens and U. dioica to S. aureus and L. monocytogenes, respectively. In conclusion, the analyzed plant extracts have considerable biological activity.
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    Obtención de un péptido antimicrobiano autoescindible inducido por inteina utilizando un sistema de expresión en Escherichia coli
    (Universidad Técnica de Ambato. Facultad de Ciencia e Ingeniería en Alimentos y Biotecnología. Carrera de Biotecnología, 2023-03) Cordones Chimborazo, Kerly Lissette; García Solís, Mario Daniel
    Nowadays, there is a high prevalence of antibiotic resistance, which poses a danger to public health. In response to this global problem, arises the creation of antimicrobial peptides (PAMs), due to the wide antibacterial spectrum they exhibit. Based on this, cecropins sequences were used to design a peptide through ancestral reconstruction, from which an ancestral peptide called CRP_N0 was obtained. The current methods for the production of PAMs are chemical synthesis, plant cell production and direct extraction from natural sources. However, these methods have a high economic value and a low efficiency. Therefore, the peptide CRP_N0 was expressed by an intein-induced self-splitting system linked by its N-terminal end to six histidines. The six-histidine label was used to purify the fusion protein intein-CRP_N0 and the removal of intein from the peptide CRP_N0. The construction was inserted into the plasmid pET-11b and expressed in Escherichia coli BL21 pG-Tf1. To maximize the expression of the fission protein, different induction times were tested with IPTG and the optimal expression time was determined to be 4 hours. In addition, an excision test was also conducted in which different temperature and pH conditions were evaluated to induce self-excision of inteine, where it was determined that at 25 degrees Celsius and a basic pH (10) a high yield is obtained in the cutting of intein.
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    Caracterización y evaluación de la actividad antimicrobiana de una cubierta biodegradable de almidón de yuca enriquecida con aceite esencial de lavanda Lavandula angustifolia mill
    (Universidad Técnica de Ambato. Facultad de Ciencia e Ingeniería en Alimentos y Biotecnología. Carrera de Biotecnología, 2022-09) Guevara Morales, Christopher Josue; Tubón Usca, Irvin Ricardo
    Biofilms were made from cassava starch (5 percent weight on volume) and gelatin (5 percent weight on volume), plasticized with glycerol (3 percent weight on volume). The influence of the incorporation of different concentrations of essential oil of Lavender (Lavandula angustifolia mill) 1; 2.5; 5 and 10 percent, on the physical-chemical properties and antimicrobial activity of the biodegradable films produced. At a higher concentration of essential oil, the films become opaque and present a yellowish color, they are also heterogeneous and rough. The thickness and the Water Vapor Permeability (WVP) increase as the concentration of the essential oil increases. On the other hand, the solubility, swelling capacity and water vapor transfer rate (WVTR) show a tendency to decrease as the concentration of the essential oil increases. The humidity does not present a clear trend since it decreases up to a concentration of 2.5 percent and increases from the concentration of 5 percent A.E. The microbial inhibition halos are greater as the concentration of Lavender essential oil increases, indicating that the antimicrobial action is greater on S. aureus strains (ATCC 13150) and less on E. coli (ATCC 11229). Results were analyzed from one way ANOVA using GraphPad statistical software.
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    Evaluación de la actividad antioxidante y antimicrobiana de la hoja y fruto del mortiño (Vaccinium floribundum Kunth) frente a bacterias patógenas (Bacillus cereus, Staphylococcus aureus, Escherichia coli y Listeria monocytogenes)
    (Universidad Técnica de Ambato. Facultad de Ciencia e Ingeniería en Alimentos y Biotecnología. Carrera de Biotecnología, 2022-09) Guamán Poaquiza, Edith Johanna; Tubón Usca, Irvin Ricardo
    The resistance of multiresistant bacteria to antibiotics is a global health problem, which has generated various infectious diseases transmitted by contaminated food. Therefore, the OMS promotes innovation and research of new sources that counteract this problem. For this reason, this research project aimed to evaluate the antioxidant activity of leaves and fruits of V. floribundum Kunth and the antimicrobial activity against pathogenic bacteria. First, ethanolic extracts were obtained, resulting in yields of 11,189 and 41,163 percent of leaf and fruit extract, respectively. The qualitative determination of secondary metabolites was developed through phytochemical assays and metabolites were obtained such as: flavonoids and tannins in the leaf and flavonoids, tannins, phenols and diterpenes in the fruit. The antioxidant capacity with the DPPH technique was performed, where 86,422 and 27,930 percent of the leaf and fruit were obtained. Finally, the agar diffusion method was used to evaluate the antimicrobial activity. The inhibition halos in the leaf extract were: L. monocytogenes (20,667 mm), S. aureus (17,833 mm), B. cereus (18,500 mm) and E. coli (13,667 mm) and in the fruit extract: L. monocytogenes (14,000 mm), S. aureus (11,667 mm), B. cereus (11,500 mm) and E. coli (9,833 mm). The best percentage of inhibition was of S. aureus with 89 and 38,4 percent of the leaf and fruit with Vancomycin and with Gentamicin L. monocytogenes obtained 68,3 and 35 percent of the extract of the leaf and fruit.
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    Actividad antimicrobiana de aceites esenciales de plantas
    (Universidad Técnica de Ambato. Facultad de Ciencia e Ingeniería en Alimentos y Biotecnología. Carrera de Biotecnología, 2022-03) Rojas Hechavarría, Miguel Alejandro; Arancibia Soria, Mirari Yosune
    Essential oils are volatile compounds product of the secondary metabolism of plants, these can have antimicrobial activity for both bacteria and fungi due to the varied composition of terpenes, phenols, among other molecules, this allows these compounds to be multipurpose in several branches of the industry such as pharmaceuticals or cosmetics, in this last one they also have antioxidant activity. The activity of the essential oils will be different for each plant and for each organism, to obtain a great variety of results, the individual activity of 47 plants was specifically searched, in which they were tested against different types of bacteria and fungi, once the information was collected it was classified according to their results, these focused on tests of inhibition halo using diffusion disc, in which a certain amount or concentration of essential oil is tested to reveal how strong the antimicrobial activity is. Based on these results that are presented in different research studies, they were classified according to their antimicrobial activity as high, moderate, low and no activity. Essential oils have a very varied activity and the information collected is a sample of the great potential that this type of compound can have, so the main objective has been to collect all the relevant information on the subject that can be found in databases of scientific data to facilitate future work with these types of compounds.