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 Garcia, Guillermo
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.
Estudio de la micota ambiental de tres edificios de la universidad Santiago de Cali, Colombia
(Universidad Santiago de Cali, 2019) Lasso Ceballos, Ana María; Caicedo Bejarano, Luz Dary
The quantification of the environmental load in the indoors of the buildings (1, 3 and 4) of the University Santiago De Cali, Colombia and in their corresponding responses to the results to obtain a load value. A volumetric method and Dicloran Bengal chloramphenicol (DRBC) and CHROMagar Cándida culture media were used for sampling. The identification of the fungi was carried out based on macro and microscopic characteristics. Parallel to the sampling the relative humidity and temperature of each space studied was determined. This study was conducted for quarterly periods during twelve months (March 2018 to march 2019). In the study of environments of the three buildings was detected a total of 82393 colony forming units (CFU/m3) of which 60053 CFU/m3correspond to indoor environment. The results obtained showed that it was not possible to establish a correlation between the temperature and the CFU/m3 found inside the three buildings, but for the relative humidity in relation to building 4.The genera Cladosporium, Fusarium, Penicillium and Aspergillus were identified as the most prevalent allergenic fungi in this study. The results in the quantification revealed that the fungal burden exceeds the limits accepted for internal environments (500 CFU/m3) according to the World Health Organization (WHO).
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
Biota fúngica en fosas nasales de trabajadores de tres edificios de la universidad Santiago de Cali y su relación con síntomas de alergias respiratorias
(Universidad Santiago de Cali, 2019) Castillo Tellez, Beatriz Angélica; Caicedo Bejarano, Luz Dary
Allergenic fungi enter through the air to nostrils and may be responsible for some respiratory allergies. The objective of the present study was to determine the relationship between allergies diagnosed and undiagnosed according to the results obtained from the adapted survey of ISAAC (International Study of Asthma and Allergies in Childhood) and the fungal load of the nostrils of workers of three buildings of the Santiago de Cali University. The samples taken from the nostrils were made with sterile swabs and the subsequent sowing was done on Sabouraud dextrose agar, sunflower seed agar and Candida CHROMagar. In 100% of the workers (126) who participated in the study, allergenic fungi were isolated. The highest prevalence of allergenic fungi in the workers of the different buildings was obtained by the workers of block 1, finding significant statistical differences, for the genus Fusarium sp, (p=0,0018 Kruskal Wallis) and Penicillum sp, (p=0,0080 Kruskal Wallis), but not for Cladosporium sp, Alternaria sp and Aspergillus sp; likewise, the biggest fungal load was presented by the workers of this building. When analyzing the fungal 6load found in the nasal passages and its relation with the presence of symptoms of respiratory allergies, it was established that there was significant statistical association with the genus Fusarium sp (p=0,0430 Wilcoxon Mann Whitney) and not for Cladosporium sp (p=0,1918, Wilcoxon Mann Whitney) which was the most frequently isolated genus.
Caracterización molecular de aislados de Enterobacter cloacae resistentes a carbapenemes portadores de los genes blaKPC, blaNDM, blaVIM y blaOXA-48, provenientes de la red de laboratorios públicos y privados del Valle del Cauca
(Universidad Santiago de Cali, 2019) Guerrero De La Cruz, Daniela Andrea; Restrepo Falco, Aura
The production of beta-lactamase enzymes by some species of enterobacteria is a serious public health problem because it causes the loss of therapeutic efficacy to beta-lactam antibiotics, which are currently used as the first alternative for the management of infections caused by Gram-negative bacteria. In this work, the molecular characterization of 32 phenotypically resistant Enterobacter cloacae clinical isolates of cephalosporins and carbapenemes, from a private and a public entity, located in the city of Cali, was carried out. In order to detect the genes involved in resistance to these antibiotics, the polymerase chain reaction technique was used to amplify the genes encoding carbapenemases: KPC, NDM, VIM and OXA-48. It was obtained that 50% (16/32) of the isolates are carriers of the blaKPC gene, while the presence of blaNDM, blaVIM and blaOXA-48 genes was not detected. The results of this study indicate that the allele that circulates in the isolates is KPC-2 and that they are not genetically related. The results indicate that 81% of patients infected with the enterobacteria carrying KPC carbapenemase come from private medical centers, 81% are male and 44% of those affected are older adults (60 years and older). Knowing the genes involved in carbapenemes resistance in these clinical isolates is an important step towards the development of specific strategies to prevent the spread of this multi-drug resistant pathogen in the municipality of Cali.
Evaluación de la capacidad inhibitoria de extractos de curuba y moléculas bioactivas sobre el crecimiento de mycobacterium smegmatis mc2155.
(Universidad Santiago de Cali, 2019) Anacona Sánchez, Paola Andrea; Aranaga Arias, Carlos Andrés
The intrinsic resistance that mycobacteria show to some disinfectants and antibiotics makes them a growing public health problem. Due to the fact that natural products and their derivatives have been shown to be a source of new antimicrobials, the effectiveness of hexanic, ethanolic and methanolic extracts of cascara and pulp of the fruit of the curuba (Passiflora mollisima) and some chalcone molecules synthesized by the Research Group of Heterocyclic Compounds of the Universidad del Valle (Colombia), on the growth of Mycobacterium smegmatis mc2155. The results showed that the hexanic extract of peel and a chalcone molecule, were able to inhibit the growing mycobacterium at concentrations of 1 mg/ml and 100 μM, respectively. This demonstrates the potential of curuba, to obtain molecules that, like the chalcones, serve as the basis for obtaining and designing new drugs.
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; Fernando D¨vries, Richard
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.
Correlación instrumental y sensorial de la calidad de una muestra de yogurt de la empresa fructilacteos
(Universidad Santiago de Cali, 2019) Giraldo, María, Camila Erazo; Ramírez Navas, Juan Sebastián
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.
Diseño, síntesis y actividad biológica de péptidos antimicrobianos catiónicos
(Universidad Santiago de Cali, 2019) Vargas Carabalí, Lina Fernanda; Oñate Garzon, Lina Fernanda
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
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%.
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.
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
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.
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.
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; Péttry Valencia, Drochss
Mediante la técnica electroquímica de voltamperometría cíclica, se modificaron superficies de carbono con películas de 1,10-fenantrolina para la electrorremediación de aguas contaminadas. Para esto, se realizó la reducción electroquímica de 1,10-fenantrolina en medio ácido sobre electrodos de carbono (carbón vítreo y minas de lápiz). Posteriormente, la modificación de las superficie fue comprobada por la oxidación electroquímica de las superficies, en un blanco de ácido sulfúrico 0.100 mol L–1, mostrando dos picos de oxidación electroquímica a 0.48 y 0.80 V vs Ag/AgCl, que evidencian la modificación de las superficies. Los resultados comparados con literatura permiten afirmar que ocurre la pasivación de la superficie con moléculas de 1,10-fenantrolina. El grado de modificación es dependiente del número de ciclos voltamperométricos realizados y para garantizar la modificación completa de las superficies de carbono, se realizó la reducción electroquímica de las superficies en una solución de 1,10-fenantrolina en medio acido, por 15 ciclos de barridos voltamperométricos. Estas superficies modificadas fueron utilizadas para la electrorremediación de soluciones que contienen plomo y mercurio con concentraciones conocidas. Se optimizaron parámetros como pH y potencial de deposición para la electroremediación utilizando cronoamperometría de doble pulso de potencial por 800 s, encontrando que el mejor potencial de deposición es -0,700 V vs Ag/AgCl y el rango de pH óptimo de trabajo está entre 3.00 y 5.00 para la remediación. Finalmente, la espectroscopia de absorción atómica determinó que la cantidad de plomo eliminada fue del 41.55% y 40.91%, cuando se estudió el efecto de potencial y pH, respectivamente. En la electrorremediación del mercurio, se eliminó el 22.42% cuando se evalúo el efecto de potencial y en el estudio del efecto de pH se alcanzó una eliminación del 53.87%. Las superficies aquí generadas pueden ser utilizadas para la remediación de ríos contaminados con metales pesados.
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; Castillo Ayala, Jorge Enrique
El método de inmersión o “Dip-Coating” es utilizado para la obtención de películas delgadas sobre diferentes superficies y con un amplio rango de aplicación; este consiste en la inmersión y posterior extracción de un sustrato dentro de una solución precursora para la formación de la película. En este trabajo se realizó la calificación de un dispositivo de inmersión de bajo costo elaborado en la Universidad Santiago de Cali y se ejecutaron recubrimientos sobre sustratos de acero inoxidable con TiO2/Hidroxiapatita por la técnica de química húmeda. Para la calificación se evaluaron parámetros de velocidad y tiempo de inmersión, abordando la calificación de instalación, desempeño y diseño (IQ, PQ y QD respectivamente); la síntesis de Hidroxiapatita se realizó por precipitación controlada y se analizaron las muestras secas por IR/ATR y TGA-DSC obteniendo unos picos característicos del compuesto y un buen comportamiento térmico, además se analizaron los revestimientos realizados utilizando técnicas espectroscópicas obteniendo los depósitos esperados en los sustratos y obteniendo una relación de Ca/P de 1,57.
Validación secundaria del metodo filtración por membrana para cuantificar la remoción de Escherichia Coli en muestras de aguas tratadas con filtros caseros
(Universidad Santiago de Cali, 2019) Martínez Rivera, Jorge Iván; Rivera Sánchez, Sandra Patricia
Con el fin de contribuir en la competencia para que laboratorio de la universidad Santiago de Cali pueda obtener certificaciones futuras en sus técnicas microbiológicas y con el apoyo de nuevas tecnologías de desinfección y tratamiento de agua proporcionadas por la micro empresa REPLACOL con sus dos modelos de filtros caseros de olla cerámica impregnado de plata coloidal (EKOFIL) y reforzado en su interior con una columna de carbón activado granular, también impregnada de plata coloidal (EKOFIL PLUS), diseñados para eliminar partículas suspendidas en el agua incluyendo microorganismos, se busco como Objetivo: realizar la validación secundaria de la técnica filtración por membrana para evaluar la remoción de Escherichia coli en muestras de aguas sintéticas provenientes de filtros caseros EKOFIL Y EKOFIL PLUS.
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; Avila Torres, Yenny
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.
Comparación de dos técnicas para la captación de esporas fúngicas ambientales en un campus universitario
(Universidad Santiago de Cali, 2019) Delgado Ñañez, Cristhian; Caicedo Bejarano, Luz Dary
The concordance of two fungal spore uptake techniques in the environments of three buildings of the Santiago de Cali University campus was evaluated. The gravimetric method of spore uptake was compared with the Omeliansky formula and the volumetric method (Air Ideal 3P). The environmental sampling was carried out quarterly for a period of 12 months using Dicloran Rose Bengal Chloramphenicol agar (DRBC). 64497 CFU / m3 were accounted for, of which 34930 CFU / m3 were isolated with the volumetric method and 29567 CFU / m3 with the gravimetric method. No significant statistical differences were observed with the two techniques used (p = 0.0739), with a significance level α = 0.05. The predominant genera obtained with both methods were Cladosporium, Penicillium, Aspergillus and Fusarium, which suggests that although the gravimetric method is not as efficient as the volumetric method, it is reliable for estimating the degree of environmental fungal contamination in a similar way to the volumetric method.
Evaluación de la remoción de salmonella spp. a partir de dos calidades de aguas sintéticas tratadas con filtros caseros
(Universidad Santiago de Cali, 2019) Castaño Hincapié, Ana Valentina; Rivera Sánchez, Sandra Patricia
Water is the main resource that abounds in the Earth. It is not renewable and has great importance, both for human consumption and for the rest of living beings. It is used for domestic uses or other purposes. The low coverage of aqueduct and sewerage in rural areas of Colombia, added to the fact that the implementation of potabilization in these areas entails a high cost, have favored the creation of new technologies that imply minor resources and accessibility, such as the homemade filters.
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
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.

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