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Item Detección de plásmidos conjugativos en aislados de Escherichia coli resistentes a beta-lactámicos provenientes de la ciudad de Cusco, Perú(Universidad Santiago de Cali, 2023) Lemos Bedoya, Mayerlin; Pantoja Ibarra, Sergio Esteban; Del Carmen Falco Restrepo, Aura Dayana; Correa Bermudez, AdrianaEscherichia coli is the most common uropathogen causing Urinary Tract Infections (UTI) in the community worldwide. Which makes it an opportune candidate for the dissemination of resistance genes at the hospital level. In recent years in Latin America, there has been an increase in ESBL-producing E.coli strains, especially in countries such as Peru, where rates of resistance to beta-lactams by ESBL-producing E.coli strains have been recorded close to the 20%. However, despite this, few epidemiological data are available and no study is known in which the presence of conjugative plasmids is directly related to resistance to beta-lactams present in the isolates. Therefore, in this study conjugative plasmids were detected in E. coli isolates from the city of Cusco, Peru. With this, the presence of plasmids will be identified in 81% of the strains evaluated and, in addition, it will be verified that 100% of the isolates have the capacity to transfer extrachromosomal information during the conjugation process. With this information, it was concluded that the three hospitals evaluated (Regional Hospital of Cusco, EsSalud and Hospital Antonio Lorena) located in the city of Cusco, are a possible reservoir of E. coli strains carrying conjugative plasmids that sustained resistance to the beta-lactam antibiotics. For this reason, the implementation of the guidelines suggested by the WHO in 2016 is recommended, in order to reduce the prevalence of multi-resistant strains at the hospital levelItem Caracterización genética de un aislado de Vibrio metschnikovii proveniente de una Planta de Tratamiento de Lixiviados en Cali, Colombia(Universidad Santiago de Cali, 2023) Gallo Pérez, José David; Del Carmen Falco Restrepo, Aura Dayana; De la Cadena Vivas, Elsa PiedadLeachate is a highly contaminating liquid substance that is formed when water percolates through the waste, extracting dissolved or suspended solids that may contain heavy metals or antibiotics, increasing the probability of finding bacteria that possess resistance genes to these, representing a potential risk to human, animal and environmental health. Previous studies carried out in a leachate treatment plant in Cali reported an isolate of Vibrio metschnikovii with a resistance profile to ampicillin/sulbactam, piperacillin/tazobactam and cefoxitin, in a lagoon without physicochemical treatment. The aim of this study was to sequence the genome of this isolate to expand the knowledge about its genetics, related to genes involved in antimicrobial resistance and virulence factors, in addition to generating valuable information that could be used for risk management and control of the spread of resistance genes. To this end, the genome was sequenced using Illumina's NovaSeq6000 technology, once the quality of the raw sequence was assessed (FastQC), adapters were removed (FastClipper), then de novo assembly (SPAdes) was performed, and its quality was assessed (QUAST). To annotate genes, the BV-BRC platforms were used, it analyzes data and annotates bacterial and viral genes, Kbase-Prokka performs rapid annotation of prokaryotic genomes and CGE-ResFinder identifies acquired antibiotic resistance genes, the genes identified were: blaCARB-9, involved in resistance to beta-lactam antibiotics; the arsD gene, which confers resistance to metals such as arsenic; the mdtK (or norM) gene that codes for an efflux pump belonging to the MATE family that expels antibiotics, among other toxic compounds; as well as various virulence factors that favor survival in stressful environments. In conclusion, the propagation of resistance genes presents in bacteria whose habitat is leachates could be a problem for human and animal populations, which is why their due treatment and control before their inclusion in the environment must be guaranteedItem Ensamblaje de novo del genoma de un aislado de Pseudomonas sp como Bacteria Promotora del Crecimiento de las Plantas (PGPB) basado en la tecnología de secuenciación MinION(Universidad Santiago de Cali, 2023) Perlaza Barragán, Julián Andrés; Corrales Ducuara,Alba Rocío; López Álvarez , Diana CarolinaModern agriculture has forced an increase in the production of agricultural crops by providing the intensive use of chemical fertilizers that have had a devastating effect on soil quality. In addition, climate change has generated a negative impact on the quality of soils used for agriculture, thus putting food security at risk. PGPRs are promoted as a sustainable application that will reduce the use of chemical fertilizers and pesticides. Through nanopore sequencing of the MinION platform, the sequence and de novo assembly of the genome of a Pseudomonas protegens isolate from Galleria mellonella larvae found in plantain soils was obtained. The chromosome had a size of 7,055,130 (bp) with a total of 6399 protein-coding genes. On the other hand, a total of 9 genes involved in promoting plant growth were identified, of which genes that encode phytohormones, phosphorus solubilizers and denitrifying enzymes were present. In addition, 25 genes involved in the control and suppression of phytopathogens were found, being mostly siderophores, antibiotics and biocontrol factors. The results showed that the isolated Pseudomonas protegens is a possible candidate as a biocontrol agent for use in crops of agricultural interesItem Mejoramiento de la producción de carotenoides en la cepa Rhodotorula mucilaginosa AJB01 mediante evolución adaptativa en laboratorio(Universidad Santiago de Cali, 2021) Vivas Parra, Aura Elena; Ramírez Castrillón, Mauricio; Dávalos Vélez, Andrés FelipeAdaptive laboratory evolution or evolutionary engineering, has been used for many decades to enhance critical features of industrial strains, such as carbon source utilization, tolerance to adverse environmental conditions and resistance to chemical inhibitors, due to its simplicity and effectiveness. In this investigation, an evolutionary directed experiment was carried out in order to improve total carotenoid production in R. mucilaginosa AJB01, by using an oxidative stress as the selective pressure, with increasing periodic doses of hydrogen peroxide (H2O2). The performed experiment allowed a sustained selection of higher carotenoid-producing phenotypes, surpassing the parental concentration of 170,0 mg/g in 20,1% with a total of 205,8 mg/g. This study represents the first approach in the developement of an improvement model for the production of carotenoids in yeasts belonging to Rhodotorula. Based on the achieved results, the continuation of the developed model promises a high potential in the acqusition of widely adapted higher carotenoid-producing phenotypesItem Levaduras oleaginosas aisladas de dos lagos de la Universidad del Valle(Universidad Santiago de Cali, 2020) Benavides León, Tatiana Andrea; Ramírez Castrillón, Mauricio; Osorio Cadavid, EstebanIn Colombia, the study of the biotechnological, microremediative, and industrial potential of the yeast community has been limited, since most of the research has only focused on species of clinical interest. Some yeasts are oleaginous by accumulating lipids between 20 to 70% of their weight, showing great potential in the biofuel and food industry. The objective of this study was to evaluate and characterize the lipid composition of yeasts previously isolated from two lakes of the Universidad del Valle. This study gravimetrically evaluated 25 yeast strains, where 52% showed oleaginous capacity with a range between 0.045 g/L and 0.598 g/L. The selected strains with lipid accumulation potential were identified at the molecular level. The Aureobasidium sp. LC112 is suggested as promising due to its high biomass production, lipid yield of 38.2% and a lipid profile with 50% saturated fatty acids, 25% monounsaturated and 25% polyunsaturated. Therefore, this strain has great potential in the biofuel, pharmaceutical, food and cosmetic industriesItem Caracterización molecular y epidemiológica de una cohorte de casos de microfilariasis canina identificados en Cali y municipios cercanos(Universidad Santiago de Cali, 2020) Espinosa Rosero, Nathaly; Rosero López, Ángelo Enrique; Castellanos Sánchez, Angélica María; Vera Lizcano, OmairaFilariae are nematodes that affect different mammals. In canines, the filariae first larval stage is called microfilaria that can be observed circulating in peripheral blood. Dirofilaria immitis is the most prevalent specie worldwide, causing heartworm disease, that can be fatal in canines and affect humans. The objective of this study was the identification of cases of canines with filariasis in Cali (Colombia) and close localities in of one-year period, detected by microscopy, serological methods and the determination of the species by the molecular method PCR–RFLP. In eight cases PCRsequencing was performed. As a result, a total of 102 cases of canine filariasis were detected, of which 82 were molecularly analyzed, finding that 55 (67%) of them corresponded to the Acantacheilonema reconditum specie. The filarial species in the remaining cases could not be molecularly identified, probably due to low parasitaemia by the time of blood sampling. The filariasis cases were statistically associated with males who presented clinical signs of anemia, with low levels of hemoglobin and hematocritItem Evaluación de procesos fotoquímicos de oxidación avanzada para la inactivación y/o reactivación de una cepa de Candida albicans(Universidad Santiago de Cali, 2024) Zamora Adrada, Emerson Yesid; Guerrero Rivera, Daniela; Caicedo Bejarano, Luz Dary; Castro Narváez, Sandra PatriciaCandida albicans is a priority fungal pathogen for the OMS, opportunistic, causing diseases in skin, mucous membranes, and invasive fungal infections with very high mortality rates. This study determined the effect of some advanced oxidation processes on the inactivation and reactivation rate of a C. albicans strain. For this, 9 inactivation assays (PDS, PMS, H2O2, UVC, PDS/UVC, PMS/UVC, H2O2/UVC, Photo-Fenton pH 3.4, Photo-Fenton pH 7.29) and 4 reactivation assays (UVC, PDS/UVC, PMS/UVC, H2O2/UVC) were performed. The best results were obtained with the UVC/PMS and UVC/H2O2 combinations with 100% removal at 30 seconds (s), followed by UVC/PDS from 45s and UVC light at 60s. The oxidants PMS achieved 98% removal at 60s; PDS 89% at 80s; H2O2 60% at 80s. The Photo-Fenton process showed a maximum removal of 41% and 50% at pH 3.4 and 7.29, respectively, at 60s. Regarding the reactivation of the C. albicans strain, it was determined that the minimum exposure time for the inhibition of C. albicans without reactivation was 45s for PMS/UVC and 60s for UVC, PDS/UVC, and H2O2/UVC. In conclusion, these advanced oxidation processes were effective methods for the inhibition of a C. albicans strain, with the PMS/UVC assays being the most efficient, followed by H2O2/UVC, PDS/UVC, UVC light, PMS, PDS, and finally, H2O2Item Revisión sistemática sobre carotenoides producidos por hongos: Condiciones de cultivos y sus aplicaciones industriales(Universidad Santiago de Cali, 2025) Zuñiga Bañol, Juan José; Martínez Garay , CarlosCarotenoids are natural pigments with recognized antioxidant, anticancer, antimicrobial and neuroprotective properties, which make them compounds of high value for the food, cosmetic, pharmaceutical and aquaculture industries. Due to their increasing demand, filamentous fungi and yeasts have gained relevance as biotechnological platforms for their production, offering an alternative to synthetic pigments. This systematic review analyzed 70 studies published between 2017 and 2024, identifying carotenoids such as β-carotene, astaxanthin, torulene, torularhodin and lycopene, produced by fungal genera such as Rhodotorula, Phaffia and Saccharomyces, among others. The genus Rhodotorula was especially highlighted for its high biosynthetic capacity, mainly of β-carotene and astaxanthin. It was shown that the optimization of cultivation parameters such as pH, temperature, agitation and carbon source is essential to improve yield, as well as the use of agroindustrial residues (crude glycerol, sugarcane bagasse, lignocellulosic hydrolysates), which reduce production costs. Some studies reported yields higher than 800 mg/L of astaxanthin and 14,000 mg/100 g wet biomass of β-carotene in Blakeslea trispora, which validates certain technical and economic strategies for industrial scale-up. Overall, the findings of this review underline the potential of fungal carotenoids as a natural, efficient and environmentally friendly solution, although various technical, genetic and economic strategies still need to be refined to achieve fully cost-effective large-scale processesItem Infecciones hospitalarias bacterianas asociadas a pacientes tratados con Diálisis. Revisión sistemática(Universidad Santiago de Cali, 2025) Escobar Guzmán, Natalia; Duque, Juan DiegoNosocomial infections in patients undergoing dialysis treatment constitute a high-impact clinical complication, closely related to immunosuppression, the presence of comorbidities, and, especially, to the use of vascular access devices such as central venous catheters (CVCs). Despite advances in prevention and control, a high incidence of bacteremia and sepsis episodes associated with hospital care persists. To analyze this problem, a systematic review of scientific literature published between 2019 and 2024 was conducted, using databases such as PubMed, Scopus, Web of Science, and ScienceDirect. The PRISMA methodology was applied with the support of digital tools such as Rayyan and Zotero, employing Boolean operators and specific criteria that included vascular access type, microorganisms involved, and hospital practices. The main risk factors identified were vascular access type, noncompliance with hygiene protocols, patient immunological status, and inappropriate antimicrobial use. The most frequent microbiological profiles included Staphylococcus aureus, Escherichia coli, Klebsiella pneumoniae, and Pseudomonas aeruginosa. The evidence gathered supports the need to reduce the use of CVCs in favor of arteriovenous fistulas, as well as to strengthen aseptic protocols. Furthermore, ongoing training of healthcare personnel and active epidemiological surveillance are fundamental pillars for mitigating the risk of infections by multidrug-resistant pathogens, improving patient safety and the quality of care in dialysis unitsItem Revisión sistemática: Comparación de las condiciones fisicoquímicas y microbiológicas de los residuos utilizados en un biodigestor con el resultado de operación para la optimización de proceso(Universidad Santiago de Cali, 2025) Ramírez Tabares,Cristian; Bautista Carrillo, Jonathan Arturo; Julián Alonso Rojas BarretoAlthough the functioning of biodigesters has been extensively studied conceptually, technological advancements still rely on the interaction of microbial communities and the selection of conditions adaptable to the substrate. This study presents a systematic review aimed at comparing microbial populations, types of waste, and the physicochemical conditions of the process. Optimal physicochemical and microbiological conditions, such as temperature, pH, and inoculum types, were analyzed to identify how they impact biogas production efficiency. The findings highlight key substrates influencing microbial activity, such as corn residues and cattle manure, which are particularly effective in biogas generation. Other inoculums, such as algae and anaerobic sludge, also presented good methane yields, highlighting that each waste has its own conversion potential depending on the specific operating conditions. This analysis provides a basis for optimizing the use of biodigesters in sustainable waste managementItem Diversidad de la microbiota en vinaza: Población microbiana y desafíos para la sostenibilidad en la producción de etanol(Universidad Santiago de Cali, 2025) Castañeda Sánchez, Sebastián; Oñate Garzón, José FernandoIn the sugar sector, bioethanol production has become a key alternative to synthetic petroleum-derived ethanol, seeking to mitigate environmental impact. However, the increase in bioethanol production has led to an increase in the generation of vinasse (12 L of vinasse/1 L of ethanol), a byproduct that poses significant environmental challenges. During fermentation, raw materials such as honey and molasses are used, along with specific yeasts. The accumulation of vinasse has prompted the search for strategies to minimize its impact, such as recirculation and methods like Biostyle. Consequently, studies have been conducted to analyze the environmental impact of vinasse after distillation and concentration. Accordingly, an objective was set to review information from previous studies on the microbial diversity found in sugarcane vinasse after distillation. The presence of diverse microbial communities that influence process stability was evident, some of which can affect the yield of alcoholic fermentation, generating products of low value. Likewise, microorganisms with potential for utilizing vinasse in valorization strategies such as composting, recirculation in fermentation processes, and environmental mitigation were reported. These included fermentative (Lactobacillus), biogas-producing (Desulfotomaculum), denitrifying (Pseudomonas), and acidogenic (Caproiciproducens) bacteria. These findings highlight the importance of understanding the microbiota to optimize its management and contribute to the sustainability of the bioethanol production processItem Caracterización microbiológica y molecular de transconjugantes obtenidos a partir de aislados de Escherichia coli resistentes a cefalosporinas provenientes de la ciudad de Cusco, Perú(Universidad Santiago de Cali, 2025) Martinez Arroyabe, Daniela; Correa Bermúdez, Adriana; Falco Restrepo , Aura DayanaEscherichia coli (E. coli) is a gram-negative, facultative anaerobic bacillus that lives in the intestines of warm-blooded animals and in the environment. In recent years, there has been a worldwide increase in resistance to beta-lactam antibiotics, especially third-generation cephalosporins. This increase has been reported to be associated with the horizontal transfer of the plasmid genes blaTEM, blaSHV, and blaCTX-M, through the process of conjugation, which represents an epidemiological risk to global public health. The frequency of third-generation cephalosporin-resistant E. coli isolates is high in Latin American countries, including Peru. In a previous study, transconjugants of cephalosporin-resistant E. coli isolates from Cusco, Peru, were obtained; however, the genes transferred by conjugation were not characterized. Therefore, in this study, the microbiological and molecular characterization of E. coli transconjugants obtained from third-generation cephalosporin-resistant isolates from Cusco was performed. This allowed us to detect the presence of the blaTEM gene in 7.1% and the blaCTX-M gene in 64.2% of the strains evaluated, with 36% of genes unidentified. In addition, the antibiotic sensitivity profiles of the transconjugants were determined, identifying that 85.71% of the transconjugants showed changes in the MIC with respect to E. coli J53. Based on the results obtained, the implementation of guidelines regarding the donor strain is recommended. These results show that the plasmid conjugation process of E. coli carrying BLEE is more efficient with CTX-M than with other genes, which is associated with the widespread dissemination of this enzyme worldwideItem Caracterización de la capacidad lignolitica de bacterias presentes en el proceso de compostaje en el ingenio Incauca(Universidad Santiago de Cali, 2025) Arce Vargas, Nelson Antonio; Jaimes Loaiza, Danna Isabella; Fernández Daza, Fabian Felipe; Diaz Caicedo, Lizeth NataliaObjective: To characterize bacterial strains with ligninolytic capacity present in the composting process of The Incauca sugar mill. Methodology: Lignin was extracted from sugarcane bagasse and leaves using the Kraft method. Bacteria were isolated from nine 300 g samples collected from bagasse piles, material in process, and compost. Serial decimal dilutions were plated on MMS agar (minimal salt medium) supplemented with 5 mL of lignin. Colonies with the highest growth were selected, followed by Gram staining and species identification using the VITEK®2 system. Ligninolytic capacity was assessed by UV-Vis spectrophotometry at 260 nm. Results: A total of 18 bacterial isolates were obtained: 4 from bagasse, 6 from material in process, and 7 from compost. Of these, 76.5% were Gram-positive, exhibiting bacillus and coccus morphologies. Five isolates were identified as Enterobacter cloacae complex (n = 3) and Klebsiella pneumoniae (n = 2). The Enterobacter isolates showed higher lignin degradation, with transmittance values ranging from 0.038 to 0.041. Conclusion: Composting serves as a viable source for isolating ligninolytic bacterial species, which are characterized by their ability to colonize organic matter and environmental substratesItem Prevalencia y caracterización molecular de Staphylococcus pseudintermedius resistente a meticilina (MRSP) mediante detección del gen meca en animales domésticos: Una revisión sistemátic(Universidad Santiago de Cali, 2025) Prieto Durán, Sandra; Fernández Daza, Fabian FelipeThis systematic review analyzes the prevalence and molecular characterization of methicillin-resistant Staphylococcus pseudintermedius (MRSP) in domestic animals through the detection of the mecA gene as the main resistance marker. A total of 50 studies published between 2015 and 2025 were examined, retrieved from reputable databases such as PubMed, Scopus, and Web of Science, following PRISMA guidelines. The results reveal high variability in MRSP prevalence, with rates ranging from 0.2% to 100%, depending on country, species, and clinical setting. Brazil, Germany, and the United States reported the highest number of studies. The mecA gene was detected in 100% of MRSP strains in several studies and was frequently associated with resistance to multiple antibiotic classes, particularly β-lactams, macrolides, aminoglycosides, and fluoroquinolones. Molecular techniques, especially PCR, demonstrated high sensitivity and specificity for mecA detection, while the ST71 lineage was the most commonly identified worldwide. A significant link was found between prior antimicrobial use and the emergence of resistant strains. These findings highlight the need to strengthen epidemiological surveillance systems, optimize diagnostic methods, and promote the rational use of antibiotics in veterinary medicine as a control measure against the spread of multidrug-resistant pathogens with zoonotic potentialItem Epidemiología de H. pylori en Latinoamérica y su relación con el cáncer gástrico: Una revisión sistemática.(Universidad Santiago de Cali, 2025) Carabali Velasco, Karold Vanessa; Gafaro Montejo, AlexisH. pylori is a bacterium that colonizes the gastric tract of more than 50% of the world's population. It is characterized as a factor that predisposes individuals to develop gastric cancer through various virulence and pathogenicity mechanisms. Latin America represents one of the regions with the highest prevalence of this bacterium and gastric cancer; therefore, the present study focused on analyzing the distribution of H. pylori and its influence on the development of gastric cancer in Latin America, considering socioeconomic, environmental, and genetic risk factors. A bibliographic search was conducted in 5 databases, including ScienceDirect and Springer Link, obtaining a total of 454 articles, of which 50 met the inclusion criteria. These studies reported variable prevalences of H. pylori infection in Brazil, Argentina, Chile, Colombia, Honduras, and Cuba, with percentages ranging from 5% to 91%. In turn, gastric cancer incidences were found in Peru (15.2/100,000), Chile (13.1/100,000), Costa Rica, and Colombia (12.8/100,000). Furthermore, the virulence genes cagA and vacA were observed in the majority of positive cases of bacterial infection, establishing a positive relationship with cancer development. However, genetic factors and unhealthy lifestyles also strongly influenced the development of the disease. It is important to conduct similar analyses in other high-risk regions to allow comparison of the results obtained in this studyItem Caracterización del microbioma presente en la producción de vino de uva artesanal en Costa Rica, Ginebra, Valle del Cauca(Universidad Santiago de Cali, 2025) Rivera Quiñones, Angela Valentina; Fernández Daza, Fabian Felipe; Cuervo Mulet , Raúl AlbertoWine is a fermented beverage produced worldwide. In Colombia, the municipality of Ginebra, Valle del Cauca, is recognized for its semi-industrial and artisanal wine production, the latter being closely associated with the socioeconomic development of the community. However, these artisanal processes are not standardized, often resulting in flavor alterations. For this reason, a characterization of the microbiome present throughout the four stages of wine production was carried out, with the aim of generating training strategies to improve product quality and strengthen its market positioning. Samples were taken from the must, alcoholic fermentation, malolactic fermentation, and bottling stages. These were cultured using serial dilution up to 10⁻³ on GYC, MRS, DRBCA, and PDA agar media. Identification was performed through DNA sequencing and biochemical characterization of yeasts using the Pitt and Hocking key, which evaluates nutrient assimilation (urea, malt, arabinose, maltose, maltose-glucose, lactose, glucose, mannitol, xylose, and nitrate). Additionally, a flavor analysis was conducted by expert personnel to guide training efforts. Results showed that alcoholic fermentation was efficient, with a residual sugar content of 40 g/L. However, malolactic fermentation was incomplete, as the sensory profile revealed a high concentration of acetic acid, mainly attributed to Acetobacter pasteurianus. Despite this, the presence of Lactobacillus delbrueckii, Torulaspora delbrueckii, Streptococcus thermophilus, Hanseniaspora uvarum, Kluyveromyces lactis, and Saccharomyces cerevisiae contributed to the wine’s body, freshness, and fruity aromas, derived from esters, isoamyl acetate, exopolysaccharides, and other volatile compounds. These characteristics make this artisanal red wine a high-quality product representative of the Ginebra, Valle del Cauca regionItem Obtención de péptidos antimicrobianos a partir de la hidrólisis del suero de leche bovina por actinidina evaluados contra Escherichia coli y Staphylococcus aureus(Universidad Santiago de Cali, 2023) Daza Correa, Daniela Andrea; Rodríguez Perea, Valeria; Oñate Garzón, José Fernando; Liscano Martínez, YamilBacterial resistance is a growing problem worldwide in recent years for the successful treatment of infectious diseases, causing prolonged hospital stays, intensive care, high costs of care, unfavorable prognosis and increased mortality. Due to this situation, the search for new alternatives to conventional antibiotics available in the market has increased, such as antimicrobial peptides, which are found in different natural sources and can also be obtained from the enzymatic hydrolysis of natural proteins. Milk is characterized for being a food that contains nutritional elements, provides immunological protection and supplies active biological substances to both neonates and adults, composed of protein fragments classified as a-lactoalbumin (a-LA), b-lactoglobulin (b-LG), caseins (CN), immunoglobulins (Ig) and lactoferrin (LF), is a precursor of a great variety of bioactive peptides (BAP) generated by the enzymatic proteolysis of these fragments. The aim of the present work was to evaluate the antimicrobial from kiwi; for this purpose, the extraction of casein from milk by isoelectric precipitation was started and then the hydrolysis process was carried out with the enzyme according to the test conditions. The casein extracted and solubilized at 1% presented a concentration of 1.6 mg/mL. Once the hydrolysis was performed, it was determined that the degree of hydrolysis DH was 1.99 %, which indicated that the casein had a low degree of hydrolysis with actinidin under the conditions that were established. For the evaluation of the antimicrobial activity, the peptides were quantified by the Bradford method obtaining an estimated concentration of 0.3 mg/mL. From this concentration, double serial dilutions were performed, resulting in the inhibition of E. coli and S. aureus at concentrations of 300, 150 and 75 µg/mL of the peptide, determining that the minimum inhibitory concentration (MIC) is 75 µ/mL for both microorganismsItem Validación del método de muestreo de superficies por la técnica de contacto e hisopado (frotis) en la planta farmacéutica de Sanofi ubicada en la ciudad de Cali(Universidad Santiago de Cali, 2023) Sabogal Girón, Natalia Jhaidiris; Vargas Vargas, Juan José; Luengas Olave, Francy Soraya; Falco Restrepo, AuraThe objective of the research is to validate the surface sampling method by the contact and swab technique (smear) in the Sanofi pharmaceutical plant located in the city of Cali. The methodology was experimental, analyt-ical, microorganisms were used with ATCC certification. The results allowed to conclude that the results of the validation of the surface sampling technique showed that both techniques allowed the recovery of specific test organisms present at different sampling points that constituted the environmental monitoring program does not present statistically significant differences and trends , so both methods can be used for general monitoring of surface pollution in the plantItem Determinación de la actividad proteolítica y lipolítica de hongos filamentosos.(Universidad Santiago de Cali, 2023) Campos Nuñez, Diego Fernando; Gonzales Vargas, Iván Andrés; Fernández Daza, Fabian FelipeFungi, like living beings, are heterotrophic organisms. Throughout their evolution, fungi have developed survival strategies whose distribution extends in practically all ecosystems of our planet. The body of fungi is composed of filaments called hyphae, which bifurcate repeatedly to form networks or mycelia that grow on and within all types of living or inert organic materials, the hyphae through their walls secrete enzymes such as chitinases, proteases and lipases. In this study, proteolytic and lipolytic activity was evaluated in 70 filamentous fungi obtained from soils. Three agar preparations with different components were analyzed for each of the activities evaluated in order to determine which of them showed better resolution of the enzymatic activities. For the proteolytic activity, medium number two was used and for the lipolytic activity, medium number one was used since these allowed a better visualization of the halos. As a criterion for the evaluation of the enzymatic activity, the result was identified with the formation of hydrolysis halos around the fungus. The results showed that of the 70 fungi evaluated, 6 main genera were found which are Penicillium sp, Aspergillus sp, Geotrichum sp, Trichoderma sp, Fusarium sp, Trichosporon sp of which the genus Aspergillus sp was the fungus that had the highest prevalence in the tests of exclusively proteolytic activity as was the fungus 39-39, exclusively lipolytic represented by fungus N4 and also the genus that obtained the highest prevalence among the fungi that tested positive in both activities were fungi -12 for proteases and fungus 32LP4. These fungi can be selected for future enzyme kinetics analysis to be used as possible entomopathogenic fungiItem Evaluación de la actividad larvicida de Trichoderma harzianum y Bacillus thuringiensis sobre el gusano barrenador de la caña de azúcar Diatraea saccharalis.(Universidad Santiago de Cali, 2023) Ayala Ortega, Mabel Andrea; Perea, Esteban Murcia; Martínez Garay, Carlos AndrésThe pests present in crops are one of the biggest problems, which results in economic losses and possible diseases to the consumer. The larva of Diatraea saccharalis is identified as the main problem for sugarcane producers in Valle del Cauca, causing weight loss and sugars in the stem when the cane is ripe. The damage caused to the plant facilitates fungal and/or bacterial infections. For this reason, it is proposed to evaluate the bioinsecticidal activity of the bacterium Bacillus thuringiensis and the fungus Trichoderma harzianum on the larvae of the sugarcane borer Diatraea saccharalis. Three treatments (1x108 esp/mL, 1.25x106 esp/mL, 2x105 esp/mL) were evaluated for T. harzianum and two for B. thuringiensis (1x109 CFU/mL and 1x106 CFU/mL) in triplicate using 60 larvae for each treatment. Therefore, treatment 1 (1x108 esp/mL) of the fungus T. harzianum presented a mortality of 52.83% in 204 hours (8.5 days) and treatment 2 (1.25x106 esp/mL) a mortality of 37.74%, without showing a significant difference between the two treatments. Treatment 1 (1x109 CFU/mL) of B. thuringiensis presented a mortality rate of 96.23% at the same time. The results showed that Trichoderma harzianum does have an effect on the mortality of D. saccharalis larvae. when applied at a concentration of 1x108 esp/mL, but it is not as efficient compared to B. thuringiensis