Ciencia e Ingeniería en Alimentos y Biotecnología

Permanent URI for this communityhttp://repositorio.uta.edu.ec/handle/123456789/412

Browse

Subject: search.filters.subject.POLÍMEROS

Search Results

Now showing 1 - 3 of 3
  • No Thumbnail Available
    Item
    Expresión y purificación de una enzima PETasa obtenida mediante reconstrucción ancestral
    (Universidad Técnica de Ambato. Facultad de Ciencia e Ingeniería en Alimentos y Biotecnología. Carrera de Biotecnología, 2023-03) Quispe Gudiño, Melanie Dayana; Cerda Mejía, Liliana Alexandra
    In the world, there are a wide variety of organic polymers that have come to represent a significant problem of environmental contamination. Currently, the scientific field began to design appropriate and efficient alternatives to facilitate the recycling of plastic materials ecologically. Biodegradation by enzymes has become highly relevant in recent years due to its good capacity for plastic degradation. The present investigation aimed to express and purify an PETase enzyme obtained from an ancestral reconstruction (ASR); the ancestral enzyme was expected to have superior characteristics to I. sakaiensis PETase respect to its activity against PET and other organic polymers. The ancestral PETase N1 enzyme was expressed in E.coli Ta cells under stable conditions of 1,0 mM IPTG at room temperature, over 16 hours. The enzyme purification was carried out through affinity chromatography (FPLC) complemented with an SDS-PAGE electrophoresis to verify the presence of the ancestral PETase N1 enzyme according to its molecular weight. Over more, the purification used an extra serine protease inhibitor (PMSF) together with EDTA metalloprotease inhibitor. The activity of the ancestral PETase N1 enzyme was evaluated through degradation assays in six high-value polymers by SEM. The images obtained showed degradation features in the HDPE polymer, while in the LDPE, PS, and PVC polymers there was low activity. On the other hand, PP and PET polymers experienced a null activity of the enzyme that could be influenced by various factors.
  • No Thumbnail Available
    Item
    Microencapsulación de microorganismos mediante secado por aspersión con aplicación industrial
    (Universidad Técnica de Ambato. Facultad de Ciencia e Ingeniería en Alimentos y Biotecnología. Carrera de Biotecnología, 2022-03) Altamirano Sánchez, María Fernanda; López Hernández, Orestes Darío
    Functional products containing beneficial microorganisms are gaining popularity on the world market. The viability of microorganisms present in products can be affected during processing, storage and ingestion by the consumer. Microencapsulation by spray drying makes it possible to prolong the consumption time of said products and preserve cell viability. In spray drying, a fluid is atomized in a stream of hot air to obtain dry particles with low water content. Therefore, in the present job it is presented a review of the most recent research on the spray drying of efficient microorganisms with application in the human food, animal food, agricultural and environmental and healthcare industries, with specific reference to the best conditions that allow obtaining powders with high cell viability. The main topics covered are the types of microencapsulated microorganisms, the objective of the study, viable cell count, growth medium, encapsulating agents, operating parameters, equipment and storage conditions. Within the analysis carried out, it can be determined that bacteria, yeasts, cyanobacteria and fungi have been microencapsulated for different purposes. Especially a large number of studies on bacteria with application in the human food industry have been reported, while in the healthcare industry a minimal amount of research has been published. On the other hand, it has been determined that the genus and species, the wall materials, as well as the operating parameters significantly influence cell viability and microencapsulation efficiency.
  • No Thumbnail Available
    Item
    Extracción y microencapsulado de carotenoides con actividad antioxidante a partir de Pouteria sapota
    (Universidad Técnica de Ambato. Facultad de Ciencia e Ingeniería en Alimentos y Biotecnología. Carrera de Ingeniería Bioquímica, 2020-01) Guevara Gonzalez, Jarol Damian; López Hernández, Orestes Darío
    It is well known that carotenoids are compounds that have a high antioxidant power and their contribution to the human diet has great health benefits. The present research work focused on the extraction, microencapsulation and analysis of carotenoids present in mamey zapote (Pouteria sapota) for its antioxidant properties, based on an experimental surface design, so it was determined that the optimal conditions were 30 minutes with a vegetable-solvent mass ratio of 1:67 using 96 percent ethanol as solvent at a temperature of 70 Celsius degrees. To preserve the carotenoids against external factors, the microencapsulation process was carried out by the spray drying method, with a polymeric mixture of maltodextrin and gum arabic in equal proportions. The efficiency of the microencapsulation process was analyzed by FT-IR infrared spectrophotometry, the spectra obtained demonstrated the protection of the polymer mixture to antioxidants. The antioxidant activity was determined by an in vitro assay by the DPPH method, obtaining equivalent Trolox values of 253,21 micromoll-1 for the concentrated extract and 385,19 µmoll-1 for the microencapsulation. In addition, the in vivo antioxidant activity was analyzed through the Saccharomyces cerevisiae growth curve of the microencapsulate at a concentration of 50 mg for ml with maximum absorbances of 1,259 and 1,335 for 3 mmoll-1 and 0,5 mmoll-1 hydrogen peroxide respectively compared to vitamin C as an antioxidant model.