Facultad de Ciencias Básicas

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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%.
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, 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%.
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.
Evaluación de la aceptación y preferencia sensorial de dos variedades de helados comerciales sabor a chocolate
(Universidad Santiago de Cali, 2019) Cifuentes Rua, Roberto Miguel; Vera Pérez, Orley Aldemar; Ramírez Navas, Juan Sebastián (Director)
Two types of chocolate ice cream (Traditional and Light) were sensory characterized in three different and competitive brands of the market by means of two consumer-oriented tests (preference and acceptance), likewise, it carried out a study based on the physicochemical analyzes performed to these, to identify and explain the preference of an ice cream in particular, thus creating a database that will determine a good quality ice cream with good acceptance and competitiveness in the market. The results that had a greater preference for consumers for traditional ice cream 358 with 42.5% and for light 271 with 47.5%, additional it was concluded that additional additives to the composition such as chocolate sauce and stevia mix - Vanilla enhance the sensory parameters and certificates better acceptance, Friedman's test notes that ice cream does not differ significantly from each other in the different attributes evaluated, but preference inclinations by consumers are included.
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.
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.
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 Sebastián (Director); Rojas Renjifo, Katherine (Directora)
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.
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.
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.
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.
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.
Modificación de superficies de carbono por reducción electroquímica de 1,10-fenantrolina en medio ácido para la remediación de aguas contaminadas con plomo y mercurio
(Universidad Santiago de Cali, 2019) Crespo Martínez, Gloria Amparo; D'vries Arturo, Richard Fernando (Director); Péttry Valencia, Drochss (Director)
Carbon surfaces were modified with 1,10-phenanthroline molecules by cyclic voltammetry technique, for applications in heavy metals electrodeposition of contaminated water. The electrochemical reduction of 1,10-phenatroline was carried out, with cyclic voltammetry using carbon electrodes (glassy carbon and pencil graphite) in acid medium. The modification of the surface was confirmed through the electrochemical behavior of the surfaces, using 0.100 mol L–1 sulfuric acid blank. As result two peaks of electrochemical oxidation at 0.48 and 0.80 V vs Ag / AgCl, were observed, which evidence the modification of the surfaces. Surface modification was achieved by electrochemical reduction in an acid solution of 1,10-phenanthroline by 15 voltammetric cycles. These modified surfaces were used for the electrorremediation of containing lead and mercury solutions. Parameters such as pH and deposition potential were optimized by potential step chronoamperometry for 800s, finding that the best deposition potential is -0,700 V vs Ag / AgCl, and the optimum range of operative pH was between 3.00 and 5.00. Finally, atomic absorption spectroscopy was used to determine the amount of absorbed lead from the solution. The lead retention values were 41.55% and 40.91%, when the potential effect and pH were studied, respectively. In the electroremediation of mercury, 22.42% was eliminated when the effect of the potential was evaluated and 53.87% was eliminated in the study of the pH effect. The new surfaces generated with this work, could be used for the remediation of heavy metals contaminated waters.
Degradación de Ampicilina, Catecol y el colorante naranja II, a partir de residuos de CdS obtenidos de prácticas convencionales de Química Inorgánica
(Universidad Santiago de Cali, 2019) Vidal Ruíz, Victor Alfonso; Ávila Torres, Yenny Patricia (Directora)
The elimination of orange dye, catechol and ampicillin (products present in waste from practical work of organic chemistry and biochemistry), was carried out with cadmium sulfide (CdS). This inorganic material was obtained from of residues of acid- base Pearson's practices in the laboratories of inorganic and analytical chemistry. Cadmium sulfide is a semiconductor with a GAP 2.4-2.6 ; which allows its use as a photocatalyst in the visible region and enhances its application in the degradation of organic matter. An important source of this type of materials are the conventional practices at the laboratory level, where it is possible to obtain residues such as PbS and CdS; which are generally underutilized. In this article, the impure CdS residue was purified and characterized as was reported, previously. Subsequently, organic labs and has obtained the best parameters at pH neutral for the elimination of orange II. This behavior was compared with the transformation of catechol and ampicillin as neutral and zwitterion molecules. H2O2, KI and acetonitrile as solvent, were added in to order to evaluate synergistic effects and establish the role of the semiconductor, (huecos) h+ and OH-. This work is a contribution to the reuse of waste in teaching laboratories, which promote the recirculation water contaminated with this type of organic compounds and allows for the student to design experimental protocols that allow him to use two types of organic and inorganic waste.
Calificación de un dispositivo de inmersión para así realizar recubrimientos de TiO2/Hidroxiapatita sobre superficies metálicas
(Universidad Santiago de Cali, 2019) Martínez Bellaiza, Daniela; Morales Morales, Jimmy Alexander (Director); Castillo Ayala, Jorge Enrique (Director)
The Dip-Coating method is used to obtain thin films on different surfaces and with a wide range of application; This consists in the immersion and subsequent extraction of a substrate inside a precursor solution for the formation of the film. In this work, the qualification of a low cost immersion device developed at the Santiago de Cali University was carried out and coatings were executed on stainless steel substrates with TiO2 / Hydroxyapatite by the wet chemistry technique. For the qualification, parameters of speed and time of immersion were evaluated, addressing the operational installation, performance and design (IQ, PQ and QD respectively); the synthesis of Hydroxyapatite was carried out by controlled precipitation and the dry samples were analyzed by IR / ATR and TGA-DSC, obtaining characteristic peaks of the compound and a good thermal behavior. In addition, the coatings made using spectroscopic techniques were analyzed, obtaining the expected deposits in the samples. substrates and obtaining a Ca / P ratio of 1,57.
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.
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.
Caracterización fisicoquímica, sensorial y micológica del Kéfir de agua en jugos de frutas tropicales
(Universidad Santiago de Cali, 2019) Pedraza Morales, Yiham Stephanie; Ramírez Navas, Juan Sebastián (Director); Caicedo Bejarano, Luz Dary (Directora)
Kefir contains beneficial properties that promote health, which is why microorganisms isolated from kefir are studied for the development of functional foods. In the present study, the physicochemical, sensory and growth characteristics and phenotypic characterization of fungi present in water kefir in tropical fruit juices were determined. This experiment was done under a factorial design corresponding to the combination of two factors with three blocks and three replicas: type of substrate (pear juice, passion fruit and water with panela) and sucrose concentration (25%, 50% and 100%). The response variables were: acidity, pH, Brix degrees. For the microbiological analyzes, decimal dilutions were made, they were counted on the second and fifth day of incubation. The identification was made with API 20C and Vitek 2 (Biomérieux). Three yeast strains found from higher to lower number of CFU/mL Saccharomyces cerevisiae 1, Saccharomyces cerevisiae 2 and Zygosaccharomyces spp were finally isolated with the sensory analysis it was determined that the passion fruit drink was the one that had the best acceptance and preference on the part of consumers.

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