Química

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

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Diseño, implementación y mejoramiento de un método para la disminución del desperdicio generado durante el empaque y embalaje de harina precocida de maíz en la empresa Alimentos del Cauca S.A.
(Universidad Santiago de Cali, 2012) Valderrama González, Luis Alfonso; Garzón García, Guillermo (Director)
Using statistical process control as a tool for improvement, improved packaging process, integrating teams and encouraging the participation of the same. The application of this method of analysis of a representative sample packs precooked cornmeal able to reduce wastage of the same. This involved the development of technical and administrative skills to solve problems. It also encouraged the participation of the company's operating personnel. Developing this project has managed to launch the appropriate methodology to the particular case, facilitating the organization of control instruments for proper resource management plan.
Aprovechamiento de los lodos de salmuera de una planta cloro-soda para la producción de carbonato de sodio
(Universidad Santiago de Cali, 2018) Luna Gómez, José Luis; Ayala Cruz, Martha Isabel; Franco, Jaime Martín (Director)
A methodology was carried out to obtain sodium carbonate from the brine sludge, previously characterized by ICP-OES plasma spectroscopy. The treatment consisted of adding hydrochloric acid to the sludge to generate carbon dioxide which was absorbed in sodium hydroxide solution at different concentrations to produce sodium carbonate, with a maximum yield of 62,2%.
Síntesis asistida por cavitación acústica de metacrilato de sacarosa
(Universidad Santiago de Cali, 2018) Rojas Sterling, Juan Camilo; Orduña Ortega, Julieth (Directora)
Sucrose methacrylate was synthesized by transesterification reaction of sucrose with methyl methacrylate using homogeneous basic catalysis (sodium methoxide, NaOCH3) and heterogeneous catalysis (mixed oxides derived from hydrotalcites) with acoustic cavitation irradiation 20 kHz. Optimal reaction conditions were determined using experimental design 32 x 2 where methyl methacrylate consumptions 90.32 % and production of monoesters ≥ 80% when the reaction was catalyzed with NaOCH3 and used molar ratio sucrose: methyl methacrylate 3: 1 and temperature and reaction time of 30 ° C and 30 min respectively. The most abundant sucroester was isolated by HPLC and characterized by vibrational spectroscopy ATR-FTIR, TGA, DSC and NMR
Implementación y validación de la técnica analítica para la cualificación–cuantificación de Dienogest/Etinilestradiol tableta recubierta, por espectroscopia de infrarrojo cercano
(Universidad Santiago de Cali, 2018) Cardona Moreno, Gilma Liliana; Castillo, Jorge Enrique (Director)
In this study, the implementation and validation of the analytical technique for the identification and quantification by NIR near infrared spectroscopy of Dienogest / Etinilestradiol in Coated Tablets was developed. This methodology was developed in order to provide a quick, simple and environmentally friendly analysis technique. To carry out this study, the spectra of 24 samples were collected, corresponding to 7 placebos loaded in a concentration range of 85 and 115%, 7 placebos loaded according to the DoE, 3 batches of finished product and 7 placebos loaded for validation. The NIR records were made in the diffuse reflectance mode and compared with the HPLC reference method. The PLS multivariate calibration method (partial regression by least squares) was used for the chemometric analysis of the data. The spectral correlation between the methods was established with correlation coefficients of (R2), in the range of 0.996 and 1.00. The validation process was developed based on the criteria of the EMA guide and demonstrated the compliance of the parameters of linearity, accuracy, specificity and precision, which guarantee and allow its application as a method of analysis for the control of the production process.
Desarrollo de dos antiespumantes en Disproquin S.A.S con aplicación en el proceso de producción de papel
(Universidad Santiago de Cali, 2019) Rojas Daza, Andrés Felipe; Flórez López, Edwin (Director); Grande Tovar, Carlos David (Director)
In the paper industry the generation of foam is an important factor because it causes the paper to get porous structures affecting its quality. On the other hand, antifoam products are very effective in suppressing the foam generated in different processes. For this reason, two hydrocarbon and silicone-based antifoams were developed. For their characterization, physicochemical parameters such as pH, percentage of total solids, viscosity, particle size and density were determined. Fourier Transform Infrared Spectroscopy (FTIR), one of the components of the hydrocarbon-based antifoam, was also used. An experimental design was used to compare the efficiency of the hydrocarbon-based antifoam with a commercial antifoam followed by an efficiency study of the silicone-based antifoam. Finally, it was demonstrated that the hydrocarbon-based antifoam is more efficient as an antifoam and defoamer than the commercial product. Consequently, the silicone-based antifoam compound showed high efficiency at a temperature between 70 and 90 °C and a pH between 8 and 11. All these results show that these products could be used in different types of industries.
Aplicación de la ecuación de Schrödinger en el estudio del movimiento de moléculas diatómicas
(Universidad Santiago de Cali, 2019) Bueno Barbosa, Douglas Andrés; Parada Valencia, Alexander (Director)
Understanding the physiochemical phenomenon at the subatomic level is very important in order to know the behaviour of the matter these energy scales. It is necessary to use the Schrödinger equation in the order to describe chemical and physically the molecules. Throughout of the development of this work, we addressed the study of the Schrödinger equation and applications in the movement of diatomic molecules. The interaction potential is described by this equation, as well as the translational, rotational and vibrational energies of each molecule. Likewise, the Hamiltonian is studied in a general way, and particularly for the hydrogen molecule. We learned the main knowledge relating with Quantum Chemical and after that we focus in the study of some diatomic molecules no studied in the literature until now. Then, a phenomenological study was carried out for the BrCl molecule.
Cuantificación por HPLC de Trans-Resveratrol en la uva Isabella (Vitis labrusca) cultivadas en la Unión-Valle del Cauca
(Universidad Santiago de Cali, 2019) Ospina Ramírez, Stephanie; Castillo Ayala, Jorge Enrique (Director)
The Isabella grape (Vitis labrusca) is a variety that has been optimally adapted to the climatic conditions of La Unión-Valle del Cauca, and has had good acceptance in local markets. Currently the grape is consumed fresh and its phenolic content is unknown. According to epidemiological studies, the presence of bioactive compounds with antioxidant capacity such as trans-resveratrol, can exert a protective effect against some diseases such as cancer and cardiovascular disorders. For this reason, with this work the quantification of the trans-resveratrol present in the epicarp of the Isabella grape (Vitis labrusca) grown in La Unión-Valle del Cauca is performed, using high efficiency liquid chromatography (HPLC) with ultraviolet detector. It will ensure that the method to follow complies with the evaluation parameters (linearity, precision and accuracy). It is also intended to contribute to a methodological proposal for the extraction (liquid-liquid with acidified methanol) and purification of trans-resveratrol.
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) Velásquez Varón, Nidia Marcela; Zambrano Salgado, Yesid Fabián (Director)
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 de un sistema de gestión ambiental para la empresa Análisis Ambiental S.A.S basado en la norma NTC 14001:2015
(Universidad Santiago de Cali, 2019) Mosquera Mosquera, Gloria Estefanía; Angulo Piñeros, Nathalia; Garzón García, Guillermo (Director); Robles Pardo, Edilberto (Director)
The company ANALISIS AMBIENTAL S.A.S. provides Environmental and Sanitary Engineering services that include consultancies in water treatment plants, water, air and soil monitoring; as well as physicochemical and microbiological laboratory analysis services. These services generate impacts on the environment, and being aware of this, an Environmental Management System based on the Standard NTC - ISO 14001 of 2015 has been designed to know its nature, and mitigate and/or control them effectively.
Síntesis y caracterización de metalofármacos obtenidos a partir de Metformina con CU2+, NI2+, CO2+, ZN2+ Y BI3+, con potencial uso para el tratamiento del sobrepeso
(Universidad Santiago de Cali, 2019) Villamizar Delgado, Stephanny; D'vries Arturo, Richard Fernando (Director); Piñeros, Octavio (Director)
A series of coordination compounds of Cu(II), Ni(II), Co(II), Zn(II) and Bi(III) with a type of biguanide (known commercially as Metformin Hydrochloride) have been synthesized and characterized by means of spectroscopic techniques (FT-IR, UV / VIS), X-ray diffraction techniques and thermal analysis. From single-crystal X-ray diffraction data, it was possible to completely characterize the compound of formula [Co(C4H11N5)3](Cl)2·(H2O)2. The compound obtained crystallizes in the monoclinic space group C2/c, with one molecule per asymmetric unit and is reported for the first time. The compounds obtained will be evaluated by means of biological tests in order to clarify their actions by physiopathological mechanisms that intervene in the control of appetite, the increase in body weight and other associated metabolic factors.
Estudio estructural y supramolecular por medio de difracción 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 (Director)
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.
Diseño, síntesis y actividad biológica de péptidos antimicrobianos catiónicos
(Universidad Santiago de Cali, 2019) Vargas Carabalí, Lina Fernanda; Oñate Garzón, José Fernando (Director)
Antibacterial resistance to conventional antibiotics is an emerging problem worldwide. This urge to develop alternative antibiotics has motivated researchers to look for new molecules to overcome this resistance problem, such as antimicrobial peptides (PAMs). PAMs are important effector molecules of the innate immune system, which is the main defense mechanism for most living organisms. Alyteserin 1c, is an antimicrobial peptide secreted in the skin of the toad Alytes obstetricans characterized by having a net charge +2 (WT). Based on the WT peptide, an analogue (ΔM) was developed, which presents a +5 net charge as a result of different amino acid substitutions in the polar face of the Alyteserin 1c helix. Both peptides were synthesized using the solid phase peptide synthesis method. The yield of the unpurified synthesis was 29.7% for each peptide. After the process of purification by reverse phase high efficiency liquid chromatography, the yield was 4.95% for the WT and 13.2% for the ΔM. Subsequently, the purity of the peptides was verified using the Bruker Daltonics MALDI-TOF mass spectrophotometer, which was 95% in both peptides. Regarding the antibacterial activity, the WT peptide exhibited a minimum inhibitory concentration (MIC) of 62.5 μM and 250 μM, against the bacteria Staphylococcus aureus and Salmonella typhimuriom, respectively, on the other hand, with the ΔM MICs were obtained from 125 μM and 62.5 μM, for both strains respectively. Regarding the hemolytic activity of the peptide WT and ΔM, it was observed that the minimum hemolytic concentration is 62.5 μM in each one.
Evaluación de las propiedades fisicoquímicas del almidón termoplástico en presencia de ácido láctico
(Universidad Santiago de Cali, 2019) Pastrana Gutiérrez, Isabel; Ávila Torres, Yenny Patricia (Directora); Caicedo Cano, Carolina (Directora)
The thermoplastic starch was modified with lactic acid in the molten state, using two types of starches (achira and potato) and two different plasticizers, glycerol and sorbitol. These components were used in a 70:30 ratio (starch: plasticizer) and the addition of acidic agent was carried out in portions of 3, 6 and 9% by weight. These mixtures were obtained in a torque rheometer at 130 ° C for 10 min. The thermal characterization performed showed greater stability for the samples of TPSL> TPS, the values in the temperature of degradation varied between 230 ° C to 280 ° C, while for the thermal transitions corresponding to the temperature of gelatinization and fusion they showed a decrease in the crystallinity for the samples with 6% oleic acid, these results were consistent with the morphological analysis. The results derived from the oscillatory rheological analysis had a viscous behavior in the TPS samples, while the presence of the acid generated viscous to elastic transitions. Finally, a reduction in the hydrophilicity of the modified TPS was evidenced because some of the samples increased the value of the contact angle by up to ~ 46%.
Polímeros de coordinación de Plata(l), Cobalto(II) y Manganeso(II) con PVA inmovilizado en quitosano depositado en aluminio y vidrio erosionado
(Universidad Santiago de Cali, 2019) Díaz Canchimbo, Viviana Maria; Ávila Torres, Yenny Patricia (Directora); Caicedo Cano, Carolina (Directora)
The aim of this research work was the development of low and medium molecular weight chitosan (Q) membranes embedded with polyvinyl alcohol, which were enriched with the metal ions of: copper (II), cobalt (II), manganese ( II) and silver (I) as new bactericidal materials. The method used was electrospinning, establishing optimal deposit conditions (DC 11 cm, VB 0.01 mL / hr, V 16 Kv, T 70 min and 16% PVA) on two aluminum surfaces and eroded glass. The antibacterial activity was carried out against Staphylococcus aureus and Eschericia Coli by comparing the activity in solution and its corresponding supported membrane. The method used was Kirby - Bauer modified discs, implementing as positive controls amoxicillin at 25000 ppm and the metal salts at 50000 ppm by each transition metals. The preliminary results show bactericidal and bacteriostatic activity mediated by the nature of the metal ion, further studies are proposed in order to understand the diffusion process and the effect on the stability of the coordination polymers with respect to biological activity.
Correlación instrumental y sensorial de la calidad de una muestra de yogurt de la empresa Fructilacteos
(Universidad Santiago de Cali, 2019) Giraldo Erazo, María Camila; Ramírez Navas, Juan Sebastián (Director)
Greek yogurt samples from the company fructilácteos of campo were sensorially characterized by a semi-trained panel. Likewise, a study of the physical-chemical parameters of the same was carried out. The objective was to correlate the sensory parameters with the instrumental ones (viscosity, syneresis, pH, acidity, soluble and total solids) to identify the instrumental parameters that approximate the sensations experienced when consuming fructilácteos Greek yogurt (YGF). On the sensory side of the panelists, there was a preference for YGF for its attribute of creaminess and acidity, while on the part of the consumer a preference of 58% was observed by the YGC, mostly male consumers, however in the instrumental parameters it is revealed that most of them enter the established limit, minus the parameter of viscosity, which was 1.02.
Crecimiento de una barrera electroquímica por la electrolisis oxidativa de 2-aminotiazoles y derivados 4-x-fenil
(Universidad Santiago de Cali, 2019) Patiño Izquierdo, José Luis; Morales Morales, Jimmy Alexander (Director); Flórez López, Edwin (Director)
Se realizó el seguimiento electroquímico de los compuestos 4-(4-X-fenil)-2-aminotiazol [ X = 1a -CH3, 1b -NO2 , 1c 2-amino-5-metil-4-feniltiazol y 1d 5-(4-Bromofenil)-oxazol-2- ylamina] a través de voltamperométrica cíclica utilizando como electrodo de trabajo carbón vítreo, electrodo de referencia Ag/Ag+ y como contra electrodo espiral de platino; se estudió el efecto que producen variables como el electrolito soporte, concentración, velocidad de barrido, sustituyente y temperatura durante la electro-oxidación de cada compuesto. Se evidenció que el tamaño del electrolito soporte influye en los valores de potencial y corriente pico. La velocidad de barrido como la concentración modifican proporcionalmente los valores de corriente pico. Por otra parte, el cambio de temperatura afecta los procesos de transferencia electrónica modificando las señales de oxidación. Se evidenció que un sustituyente electro-donador facilita la oxidación del compuesto y uno electro-atractor la dificulta. Por último, se evidencio durante la electrolisis oxidativa el crecimiento de una barrera electroquímica influenciada por cambios estructurales.
Análisis estructural y supramolecular del compuesto (E)-3',6'-dihidroxi-2-((pyridina-2-yl metileno) amino) spiro[isoidolina-1,9'-xanteno]-3-ona
(Universidad Santiago de Cali, 2019) Cardona Restrepo, Camila; D'vries Arturo, Richard Fernando (Director); Rojas Álvarez, Oscar Eduardo (Director)
The crystalline structure of the compound (E) -3 ',6'-dihydroxy-2-((pyridine-2-and methylene) amino) spiro [iso-idoline-1,9'-xanthene] -3-one was solved and refined, using single crystal X-ray diffraction data. It was found that the compound crystallized in the triclinic P-1 space group. its unit cell present two molecules per asymmetric unit, which correspond to molecular conformers. Moreover, an analysis to determine the intermolecular interactions from the crystalline system was performed. It was observed that the crystal packing is formed mainly by hydrogen interactions type O-H••• N, and C-H•••O. Finally, the supramolecular interactions of the dimer were quantified using fingerprint plots, obtaining values of 41.4%, 12.9%, 11.1% and 10.4% for interactions type H•••H, C•••H, O•••H, H•••C respectively. The aforementioned diagrams were compared with the obtained for structurally similar molecules; their forms confirmed the differences at the supramolecular level of the compounds analyzed. With this project, it was possible to determine the structural and supramolecular characteristics of the compound. In addition, were acquired the basic concepts related to crystallography and supramolecular chemistry, both at a theoretical and experimental level.
Diseño e implementación de prácticas de laboratorio de Química Inorgánica I, Bloques s y p de la tabla periódica, con un adecuado acercamiento verde
(Universidad Santiago de Cali, 2019) Ríos Gamboa, Diana Marcela; Gutiérrez Moreno, Nini Johanna (Director)
Evaluación de la capacidad antioxidante y antimicrobiana de los residuos de mora (Rubus glaucus benth)
(Universidad Santiago de Cali, 2019) Araújo Pabón, Liza María; Caicedo, Luz Dary (Director)
In the commercialization of agricultural products considerable volumes of waste are generated per year, mainly due to poor handling or inadequate transportation of the product, which changes its appearance and tends to generate rejections by the consumer. With the purpose of establishing the bioprospecting of these residues, giving added value to the use of the complete fruit and making a contribution to the solution of the environmental problems derived from the inappropriate final disposal, the antioxidant capacity of alcohol extracts and lyophilized by two was determined. in vitro methods 2,2-diphenyl-1-phenylhydrazyl (DPPH) and 2,2'-azino-bis (3-ethylbenzthiazoline-6-sulfonic acid) (ABTS). The TEAC values (antioxidant capacity equivalent to Trolox) obtained from the ethanolic blackberry extract were 9.21 μmol/g; freeze-dried blackberry residue 9.03 μmol/g and methanolic extract 40.53 μmol/g applying the DPPH test and applying the ABTS test the ethanolic extract 49.28 μmol/g; lyophilized residues 60.31 μmol/g and methanolic extract 37.27 μmol/g. The in vitro antimicrobial activity of the methanolic extract was evaluated against pathogenic bacteria Staphylococcus aureus ATCC 29213, Escherichia coli ATCC 25922 and Bacillus cereus ATCC 11788, as well as the minimum inhibitory concentration (MIC), obtaining as a result 1,5mg/mL for S.aureus and 3.0mg/mL for E.coli. These results demonstrate the promising future of the use of these residues as raw materials with antioxidant and antimicrobial activity, for the food and cosmetic industry.
Extracción de antocianinas de mora de castilla (Rubus glaucus) bajo el método de ultrasonido y secado por liofilización como potencial colorante textil
(Universidad Santiago de Cali, 2019) Buritica Riascos, Jennyfer; Mera López, Demerson; Gutierrez Moreno, Nini Johanna (Director)
ynthetic dyes are recognized for their effectiveness, performance and ability to adapt to any medium or matrix, such as: food, cosmetics, textiles; but with the disadvantage that they are generators of high pollution due to the number of chemical elements used in the process among them we can find heavy metals or sulfides that generate a real environmental problem. One of the alternatives to synthetic dyes are natural dyes that are present in some flowers and fruits of nature, one of the compounds of greatest interest are anthocyanins present for example in Mora de Castilla or Mora Andina (Rubus Glaucus). The anthocyanins have little stability to the pH of the medium, the temperature, the sunlight, among others, having a limited field of application and a low yield due to losses in industrial processes. Anthocyanin extraction was performed by applying the petra - Ultrasound treatment method at different temperatures and frequencies, achieving better results with extraction at 15 ° C and 37 KHz achieving an average anthocyanin content of 1.08 g / kg, this dye was applied to wool and cotton fibers including sodium chloride as a mordant, with good results of solidity to sun exposure and rubbing and medium results of solidity to washing; which promises to improve the stability of these compounds under controlled ultrasound methods, to be applied as a potential textile dye

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