Química

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https://usc.scimago.es/handle/20.500.12421/91

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Obtención de péptidos con potencial farmacológico a partir de hidrolisis enzimática in silico de la proteína de quinua con pepsina
(Universidad Santiago de Cali, 2024) Moreno Vivas, Valentina; Garcia Leon, Nathaly; Oñate Garzon, Jose Fernando
Peptides are protein fragments, whose amino acid sequence determines their structure and function, they have various biological functions and have antimicrobial, anticancer, antioxidant, anti-inflammatory activities, among others. They are obtained through enzymatic or acid hydrolysis processes that catalyze the breaking of peptide bonds, thus obtaining bioactive peptides used in various industries due to their ability to selectively interact with other molecules, being of interest in medical research for the development of new therapies. and diagnoses. Quinoa is a rich source of peptides that contain bioactive compounds beneficial for health. Performing peptide synthesis with enzymatic hydrolysis in vitro can be complex and expensive, requiring precision in the union of amino acids and with low yields. Cheaper alternatives, such as in silico enzymatic hydrolysis, have been developed using bioinformatics tools to predict bioactive peptides. In some studies, the pharmacological potential of peptides obtained from quinoa by in silico enzymatic hydrolysis has been evaluated. This approach could significantly impact the pharmaceutical industry, facilitating the development of new drugs for chronic diseases and improving quality of life. This implies an advance in scientific and technological knowledge, especially in the pharmaceutical industry
Desarrollo de una técnica miniaturizada para la determinación de nitrosaminas en productos cárnicos mediante hs-spme-gc/ms
(Universidad Santiago de Cali, 2024) Gamboa Castillo, Miller Arbey; Ríos Acebedo, Jhon Jairo
Several studies have shown that the consumption of processed meat products is strongly linked to cancer associated with nitrosamines formed by the addition of nitrate or nitrite salts and certain amines. In this work, a method was developed for the determination of volatilenitrosamines in commercial sausages using headspace sampling by solid-phase microextraction and gas chromatography coupled to a mass spectrometer (HS-SPME-GC-MS). Two fused silica fibers were evaluated, one coated with polydimethylsiloxane (PDMS) and the other with carboxen/polydimethylsiloxane (CAR/PDMS). A fractional factorial design was employed to evaluate the influence of equilibrium time, ionic strength, extraction time, extraction temperature, and the addition of methanol on the extraction of Nnitrosodimethylamine (NDMA), N-nitrosodiethylamine (NDEA), N-nitrosodi-n-butylamine (NDBA), and N-nitrosopiperidine (NPIP) in sausages. The method was validated and applied for the determination of nitrosamines in sausages, with linear ranges between 0-50 µg/L. The coefficients of determination for the calibration curves ranged from 0.9906 to 0.9976; the limits of quantification were between 0.254 and 0.389 µg/L. The precision and accuracy of the method were within the ranges of 2.7-7.3% and 70.286.4%, respectively. The implemented method proved to be simple, rapid, and exhibited adequate accuracy, sensitivity, and precision.
Caracterización fisicoquímica de tres aceites de cocina usados para freír diferentes alimentos y los respectivos biodiesel obtenidos por transesterificación en la ciudad santiago de cali, colombia.
(Universidad Santiago de Cali, 2024) Guerra Cuaran, Lina Alexandra; Bonilla Ramírez, Luis Fernando; Tusso, Ricardo Andrés; Zambrano Salgado, Yesid Fabián (Directores)
The increase in global energy demand and the environmental concerns related to the use of fossil fuels, creates the need to find more sustainable alternatives, highlighting the relevance of biofuels to reduce dependence on oil. This study focuses on obtaining three types of biodiesel from Used Cooking Oils (UCO), from the frying of empanadas, fritters, breaded chicken and a new palm oil biodiesel used as a reference. Physicochemical tests were carried out to characterize the oils and biodiesel obtained to evaluate their potential as biofuel. Their yield was determined and 93.1% fritters, 87.5% empanadas and 90.6% breaded chicken were obtained. Based on the results of the characterization and their yield, it was determined that the biodiesel from the breaded chicken ACU has the greatest potential as biofuel and the biodiesel from the breaded chicken ACU proved to be the least suitable for such use.
Caracterización térmica y espectroscópica de sulfato de calcio dihidratado y sulfato de calcio hemihidratado
(Universidad Santiago de Cali, 2024) Correa Castaño, Leonel; Gutiérrez Moreno, Nini Johanna; Castillo Gómez, Duván Fernando (Directores)
The main objective of the present work was the thermal and spectroscopic characterization of calcium sulfate dihydrate and hemihydrate. Differential scanning calorimetry (DSC) and thermogravimetry (TGA) thermal analysis techniques were applied, finding characteristic peaks at 102 °C for the hemihydrate, 52.5 and 126.7 °C for the dihydrate. TGA showed a weight loss of 1.5% at 38.27 °C, 3% at 73.14 °C and 8.5% at 110 °C for the hemihydrate, the dihydrate showed weight losses of 17% at 56 °C, 31.6% at 110 ° C and 41.4% at 130 °C. Analysis by FT-IR revealed absorption bands between 3700 and 3500 cm-1 typical of the water molecules present and bands between 1200 and 900 cm-1 characteristic of the S=O double bond. The 20.72°, 23.38° and 29.14° for the dihydrate form. The determination of heavy metals by atomic absorption showed concentrations below 60 ppm in Na, Fe, Pb, As and Cd. The micrographs taken by SEM revealed the morphology of the crystals for the study compounds, exposing a varied number of sizes. It was found that the product has high purity, without the presence of anhydrites and low concentrations of metals such as Na, Fe, Pb, As and Cd.
Evaluación de calidad, infestaciones e identificación de componentes en cítricos mediante espectroscopia de infrarrojo cercano (NIRS)
(Universidad Santiago de Cali, 2024) Díaz Hurtado, Karol Lisbeth; Castro, Sandra Patricia
Near infrared spectroscopy (NIRS) has established itself as a crucial technology in modern agriculture, especially for citrus evaluation. This article reviewed and compared recent studies on the application of NIRS in citrus fruit quality assessment, infestation detection, and chemical component identification. The methodology employed includes the analysis of various NIRS techniques, such as reflectance and Fourier transform spectroscopy (FT-NIR), applied in different equipment and wavelength ranges. The results show that reflectance and FT-NIR techniques provide high accuracy in the evaluation of quality parameters such as soluble solids, titratable acidity, and fruit maturity and require methods validated by multivariate models. NIRS allows identification of pests not visible to the naked eye and in the determination of bioactive components such as flavonoids and organic acids, offering rapid and non-destructive evaluations, has the potential to optimize the citrus supply chain, improving product quality and facilitating real- time monitoring.
Aplicación de la espectroscopia de infrarrojo cercano (NIRS) en productos cárnicos
(Universidad Santiago de Cali, 2024) Rosero Martínez, José Miguel; Castro, Sandra Patricia (Director)
An approximation is made to near infrared spectroscopy (NIRS) as a tool for evaluating the quality and authenticity of meat products. Given the growing demand for organic meat products and the need to guarantee their integrity, NIRS stands out as an effective alternative to traditional methods. The methodology employed included literature review, data analysis and method comparison, highlighting the importance of developing more robust calibration and standardization techniques. Quality parameters that NIRS can assess, such as moisture, fat, protein, color and pH, were identified, demonstrating its ability to provide rapid and non-destructive results. Comparison between NIRS and traditional techniques such as proximate analysis revealed that NIRS offers significant advantages in terms of speed and reduced need for sample preparation. However, limitations have been identified, including the need for specific calibrations for each type of meat and the dependence on the quality of the equipment used. Recommendations include advancing the development of calibration techniques and exploring the integration of NIRS technology in real-time computing environments
Aplicación del diseño de mezclas en la formulación de sidra de manzana
(2020) RAMÍREZ NARANJO; NATHALIA, SINISTERRA AMÚ; DIANA; Ramirez Navas; Juan Sebastian
Cider is a drink with very marked characteristics with respect to other spirits; It has abundant carbon dioxide, but produces less foam than a regular beer, acquires shades of yellow in transparent and bright appearance. (Drilleau, 2005). Cider. 2. The objective of this research was to evaluate the ratio of cider mixtures from three varieties of apple (Malus Domestica): Gala, Golden and Green.
Estudio de las interacciones del péptido Alyteserin 1C y de su análogo catiónico con modelos de membranas
(2019) Sanchez Arias; Kevin; Oñate Garzón; José Fernando
Antimicrobial peptides are part of the innate immunity of most living things and have antimicrobial activity against bacterium, viruses, fungi and parasites. Their cationic characteristics make them selective towards bacterial membranes with anionic surfaces.
Estudio electrocrómico de películas de óxido de molibdeno obtenidas por dip coating
(2020) Gómez campo; david alejandro; Castro Narváez; Sandra Patricia
Se presentan aspectos relacionados con la influencia de ácido acético y peróxido de hidrógeno en la síntesis de xerosoles de diferentes fuentes de molibdeno (MoO3, (NH4)6 Mo7O24.4H2O y Na2MoO4) para la deposición Dip Coating sobre sustratos de vidrio conductor de dióxido de estaño dopadas con flúor (FTO) aplicables en la construcción de sistemas de conversión de energía electrocrómica. Los xerosoles fueron caracterizados por técnicas IR-TF, TGA, DSC y técnicas voltamperométricas que evidencia la presencia de sistemas cristalinos con tratamiento térmico a temperaturas superiores de 176°C, exceptuando para fuentes Na2MoO4, con entalpias de cristalización promedio de -0,047kJ/g
Moluscos de el charco Nariño: una mirada desde la exploración bioquímica
(2020) Caicedo Perlaza, Yaneth Angelica; Nieto Ramírez, Luisa María; Pantoja Pulido, Kriss Dayana
Mollusks are non-segmented soft-bodied invertebrates protected by a shell and constitute the basis of the diet of many communities. Our objective was to determine the biochemical composition of two species of mollusks Littorina zebra (piacuil) and Anadara tuberculosa (piangua), which are an important nutritional source in El Charco, Nariño. In total, 30 samples of L. zebra with average sizes of approximately 3cm were collected, and 30 samples of A. tuberculosa differentiated by sex, identifying 13 females with average lengths of 8.4cm and 17 males with average lengths of 6.3cm.
Mejoramiento de la calidad de agua residual de una industria gráfica por método fisicoquímico y tratamiento Fotofenton
(Universidad Santiago de Cali, 2020) Castro Ordoñez, Oscar Eduardo; Morales Lame, Ronal Leonel; Castro Narváez, Sandra Patricia
Wastewater samples from flexographic printing machines of the graphic industry characterized by having high coloration, low pH, high oxygen demand and low biodegradability to primary physicochemical treatment followed by photofenton process with the objective of reducing chemical oxygen demand (COD). Initially, the pouring generator washing process was standardized, the primary treatment consisted of coagulation with aluminum polyhydroxychloride or ferric chloride, followed by filtration with activated carbon. The Fenton process was optimized by varying the pH, and the particles of iron and peroxide. The standardization of the washing process generated a 50% COD reduction, in the primary treatment, aluminum polyhydroxychloride was the best performance. After one hour of treatment with the photofenton process with UV lamp at pH: 4.0; 40.0 mgL-1 of Fe2+ and 200 mgL-1 of hydrogen peroxide, a 97% removal was processed. Thus, by coupling the physicochemical treatment with the photofenton process, the environmental impact of the wastewater of the graphic industry is reduced.
Caracterización fisicoquímica funcional del Almidón extraído de la papa china (Colocasia Esculenta) cultivada en el pacífico colombiano
(Universidad Santiago de Cali, 2019) Hurtado Herrera, Janer Guillermo; Castillo Ayala, Jorge Enrique
The evaluation of the physicochemical and functional properties of the starch extracted from the Chinese potato tubers (Colocasia esculenta) from the municipality of Timbiquí and López de micay – Cauca was carried out. The granules had particle size around (3.5-7.8 µm in diameter for sample 1 and 3.5-7.0 µm in diameter for sample 2); a high content of % amylose (67.6 and 70.7 respectively for M1 and M2) was found compared to other botanical sources, through the colorimetric method recommended by ISO 6647. The gelatinization temperatures were (78, 6 and 81.9 ° C, respectively) by heating a solution of the starch until a stable paste formed for a few seconds. The samples showed low water solubility (0.13 M1 and 0.23 M2 g / 100 mL) and a high water retention capacity (280.3 and 391.7% at 60 ° C) compared to 226% of the cassava and 162.8% for sago: which makes it a good quality starch. The gel pastes when subjected to a % processing of light at 650 nm in a Thermo Evo 201 UV spectrophotometer was (3.4 and 4.1%) respectively. Comparing these characteristics found in this tuber with other sources of starch commonly used in the industry, it is concluded that it can be used as a promising alternative in the food industry; In addition to having a high amylose content, it is a resistant starch, providing physiological health benefits.
Diseño, implementación y certificación del sistema de gestión de la calidad bajo los requisitos de la norma ntc-iso 9001:2015 para el laboratorio de ciencias básicas de la universidad Santiago de Cali
(Universidad Santiago de Cali, 2020) Pineda Quintero, Cindy Alejandra
The Laboratory of Basic Sciences, as part of its strategic development, decides to initiate the implementation and documentation of a Quality Management System under the requirements of the International Standard ISO 9001: 2015, with the objective of guaranteeing the continuous improvement of its processes, Increase customer satisfaction and be competitively located in the local and regional market by offering a timely service and ensuring the validity and traceability of the reported data. To establish a work route aimed at achieving certification, a work plan was defined that began with the diagnosis of the Laboratory in terms of compliance with standard requirements, for this, the entire existing document base was compiled. With the information obtained, the methodology based on the PHVA cycle was designed, which resulted in the study of the context of the Laboratory, the identification of the needs and expectations of the interested parties, the definition of the process quality objectives, the scope , the identification, evaluation, analysis and map of risks associated with the process, all this to finally structure the quality manual and facilitate the revision of the Quality Management System implemented, first by an internal quality audit that delivered a favorable concept for the presentation to external quality audit, which certified compliance with the requirements of the audited standard, ISO 9001: 2015, and granted the extension of the scope for the Subsystem to which the Basic Sciences Laboratory belongs.
Estudio estructural y supramolecular por medio de difraccion de rayos x y superficies de hirshfeld del compuesto ácido 2-(e)-((4-hidroxifenil) diazenil) benzoico
(Universidad Santiago de Cali, 2019) García Carreño, Camila Andrea; D´Vries Arturo, Richard Fernando
The crystalline structure of 2-(E)-((4-hydroxyphenyl) diazenil) benzoic acid compound, was resolved by means of the intrinsic phase method using single-crystal X-ray diffraction data. It was find that the molecule crystallizes in the ortorombic crystalline system with Pbca space group. Within its unit cell there are four molecules per asymmetric unit, which are molecular conformers and form beta helix arrangement along [0 1 0] direction. Hirshfeld surface calculation was performed to determine the intermolecular interactions that contribute the most to crystalline packaging. It was possible to observe that the main contribution to the general surface is given by the contacts H…H (34.8%), followed by interactions O…H/H…O (27%) and C…H/H…C (18.6%). The energy interaction networks were calculated at a HF/3-2 level, allowing to quantify the high participation of dispersion interactions (-57.5 kJ/mol) in the formation of crystalline packaging. Keywords: crystallography, Hirshfeld surfaces, X ray, cell unit, intrinsic phase
Determinación de la Biodisponibilidad in vitro de hierro en diferentes matrices alimentarias elaboradas a partir de harinas fortificadas comerciales
(Universidad Santiago de Cali, 2019) Guzmán Aristizabal, Luisa María; Usuriaga Moreno, María Camila; Ramírez Navas, Juan Sebastian
Iron (Fe) deficiency has been recognized with the World Health Organization as a public health problem, in countries such as Colombia. It affects a large part of the inhabitants, especially children and women in gestation. In order to counteract the consequences generated by this population, the lack of this mineral establishes the need to use Iron Fortification. The aim of this work was to evaluate the effect of temperature on the iron diazability of three homemade preparations, in which commercial flours fortified with iron were used. The percentage dialysotity of Iron (Fe) was taken as an indicator of the bioavailability of said ore. The determination was made using the in vitro method, which includes an enzymatic digestion that simulates the physiological process under controlled pH conditions and subsequent quantification by atomic absorption spectroscopy. For each of the samples an estimated percentage between 4 and 5% was obtained which are according to the literature in that they do not exceed 10% absorption of non-hemine iron from food.
Generación de carbón activado a partir del residuo de cosecha de Ananas comosus para la remoción de metales pesados Plomo (Pb+2) y Cadmio (Cd+2)
(Universidad Santiago de Cali, 2019) Nidia Marcela Velásquez Varón; Zambrano Salgado, Yesid Fabián
In this study, activated charcoal was prepared from the leaves of Ananas comosus; by chemical activation, from two different pyrolysis temperatures (500 ° C and 600 ° C) and different concentrations of activating agent (20%, 40%,42,5% and 60%) in a 6: 1 impregnation ratio, with which yield percentages were obtained which varied from 47.15% to 54.82%. The surface chemistry of the coals was studied by FTIR infrared spectroscopy. The adsorbent properties of heavy metals (Pb2 + and Cd2 +) were measured from aqueous solutions, obtaining a removal percentage above 80% for both solutions. The adsorption isotherm was performed, in which the linearized experimental data fit very well to the Langmuir adsorption isotherm model, where the chemotherapy of lead and cadmium heavy metals is produced from the aqueous solutions.
Diseño e implementación de un sistema de gestión de calidad en el laboratorio cosmético khemeia green s.a.s basado en la norma NTC ISO 9001:2015
(Universidad Santiago de Cali, 2020) Chaves Hernández, Angie Liliana; Garzón García, Guillermo
The purpose of this degree work was to implement a Quality Management system in a cosmetics laboratory, in order to increase the quality of its services and the level of competitiveness in the market, with the main objective being the high recognition and preference of its services by consumers, therefore this work aims to develop an implementation plan for the Quality Management System supported by ISO / NTC 9001; 2015, which allows the Khemeia Green S.A.S laboratory to integrate its activities with a risk-based approach and continuous improvement of each of its tests, generating greater customer satisfaction. It began by making a diagnosis of the state in which the quality management system was, defining the processes that were documented and which were not, in order to structure a work plan for the development and implementation of each of the numerals present in the standard, continuously finding the improvement in the process; Once the diagnosis was completed, the requirements of ISO / NTC 9001 were condensed; 2015, and the results obtained were the sensitization of the personnel, the development of different documentary procedures, organizational structuring (organizational chart), construction of the laboratory quality policy and other documentation required with the accompaniment of senior management; The relationship that this has with the quality of the service and the product, and in an increase in productivity, was announced. In addition, the improvement of each of the laboratory areas, equipment, products, as well as the recognition and reduction of customer complaints was achieved.
Caracterización fisicoquímica y funcional del almidón extraído de la papa china (Colocasia esculenta) cultivada en el pacífico colombiano
(Universidad Santiago de Cali, 2020) Hurtado Herrera, Janer Guillermo; Castillo Ayala, Jorge Enrique
The evaluation of the physicochemical and functional properties of the starch extracted from the Chinese potato tubers (Colocasia esculenta) from the municipality of Timbiquí and López de micay – Cauca was carried out. The granules had particle size around (3.5-7.8 μm in diameter for sample 1 and 3.5-7.0 μm in diameter for sample 2); a high content of % amylose (67.6 and 70.7 respectively for M1 and M2) was found compared to other botanical sources, through the colorimetric method recommended by ISO 6647. The gelatinization temperatures were (78, 6 and 81.9 ° C, respectively) by heating a solution of the starch until a stable paste formed for a few seconds. The samples showed low water solubility (0.13 M1 and 0.23 M2 g / 100 mL) and a high water retention capacity (280.3 and 391.7% at 60 ° C) compared to 226% of the cassava and 162.8% for sago: which makes it a good quality starch. The gel pastes when subjected to a % processing of light at 650 nm in a Thermo Evo 201 UV spectrophotometer was (3.4 and 4.1%) respectively. Comparing these characteristics found in this tuber with other sources of starch commonly used in the industry, it is concluded that it can be used as a promising alternative in the food industry; In addition to having a high amylose content, it is a resistant starch, providing physiological health benefits
Diseño, implementación y certificación del sistema de gestión de la calidad bajo los requisitos de la Norma NTC-ISO 9001:2015 para el laboratorio de Ciencias Básicas de la Universidad Santiago de Cali
(Universidad Santiago de Cali, 2020) Pineda Quintero, Cindy Alejandra; Castillo Ayala, Jorge Enrique; Romero Ospina, Herman Gilberto
The Laboratory of Basic Sciences, as part of its strategic development, decides to initiate the implementation and documentation of a Quality Management System under the requirements of the International Standard ISO 9001: 2015, with the objective of guaranteeing the continuous improvement of its processes, Increase customer satisfaction and be competitively located in the local and regional market by offering a timely service and ensuring the validity and traceability of the reported data. To establish a work route aimed at achieving certification, a work plan was defined that began with the diagnosis of the Laboratory in terms of compliance with standard requirements, for this, the entire existing document base was compiled. With the information obtained, the methodology based on the PHVA cycle was designed, which resulted in the study of the context of the Laboratory, the identification of the needs and expectations of the interested parties, the definition of the process quality objectives, the scope , the identification, evaluation, analysis and map of risks associated with the process, all this to finally structure the quality manual and facilitate the revision of the Quality Management System implemented, first by an internal quality audit that delivered a favorable concept for the presentation to external quality audit, which certified compliance with the requirements of the audited standard, ISO 9001: 2015, and granted the extension of the scope for the Subsystem to which the Basic Sciences Laboratory belongs.
Identificación y Evaluación de actividad antibacteriana contra Staphylococcus aureus de Metabolitos Secundarios a partir de Extractos de Eunicea sp y Plexaurella sp
(Universidad Santiago de Cali, 2020) Mejía Gómez, Diego Alejandro; López Parra, Lizbeth Lorena; Pantoja Pulido, Kriss Dayana
The purpose of this work is to identify metabolites with antibacterial activity from two species of octocorals of the genus Eunicea and Plexaurella collected in Providencia, Colombia. For the extraction of metabolites, two solvents (methanol and hexane) were used together with the use of a rotary evaporator and column fractionation. The identification of metabolites was carried out through the application of liquid chromatography coupled to mass spectrometry, where it was seen that the compounds found were mostly fatty acids. The antibacterial activity was carried out by the sensidisk method, using a chloramphenicol disc as a positive control, where finally inhibition of Staphylococcus aureus could be seen in the complete extract.

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