Microbiología

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https://usc.scimago.es/handle/20.500.12421/93

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Desarrollo de un empaque biodegradable basado en almidón de papa y aceite esencial de orégano (Origanum vulgare) para la preservación de productos cárnicos
(Universidad Santiago de Cali, 2023) Ramírez Gutiérrez, Valentina; Falco Restrepo, Aura Dayana del Carmen; Álzate Calderón, Paola
This research focuses on addressing the environmental problems caused by the excessive use of plastic, proposing the development of biodegradable packaging to preserve meat and offer an alternative to petroleum- derived plastic packaging. Regarding the experimental part, biodegradables films were elaborated using potato starch, chitosan, and the effect of the addition of different concentrations of oregano essential oil (0%, 0.25%, 0.50%, and 1%) used as antimicrobial, in the formulation of the elaborated films was evaluated. The results showed that, in the physicochemical tests (solubility, humidity, and thickness), the films tended to increase these properties as the AEO content increased. Regarding the microbiological results, it was observed that the microbial inhibition halos are greater as the concentration of oregano essential oil increases and that the oil acts better against Gram- positive bacteria than against Gram-negative bacteria. As a general conclusion, it can be indicated that the films elaborated prove to be a viable alternative to conventional packaging, showing a promising future in this area of research
Estudio morfológico, estructural y microbiológico de películas delgadas de Ti-Ag para implantes dentales
(Universidad Santiago de Cali, 2023) Plaza Velasco, Natalia; Ramírez Calero, María Camila; Acosta, Franklin Bermeo; Garcés Constaín, Paula Andrea
The search for materials to produce dental implants has been of great interest in the fields of medicine, chemistry and biology. Generally, implants have complications due to bacterial infections or incompatibility with the human body, therefore titanium and silver stand out with great relevance due to their great capacities for harmlessness and coupling with the human body. The results of this study contributed to the investigation of what the ideal thicknesses of titanium and silver could be for the manufacture of thin films in order to make dental implants with greater antimicrobial activity. The films were structurally characterized, confirming the presence of Silver and Titanium; morphologically the roughness was characterized; The surface energy was characterized, the wettability analysis revealed that the contact angles were less than 90º, which corresponds to hydrophilic surfaces.. On the other hand, the antimicrobial activity was evaluated against Pseudomonas aeruginosa, Staphylococcus aureus and Candida albicans where the results obtained demonstrated that Ti/Ag thin films with Ti thicknesses of 180nm and 360nm have promising antimicrobial properties for dental coatings, inhibiting the adhesion of biofilms in P. aeruginosa (100%), S. aureus (100% and 96%) and C. albicans (80% and 90%) respectively, these responses are related to roughness and reflect different responses for bacteria and yeast
Evaluación de la actividad antimicrobiana de colistina encapsulada en nanopartículas de quitosano frente a bacterias extremadamente drogo resistentes
(Universidad Santiago de Cali, 2023) Barrera Vélez, Alejandro-Programa Química Farmacéutica ; Pacheco Sierra, Fabian Alexander-Programa Microbiología; Oñate Garzón, José Fernando; Polo Cerón, Dorian
Antibiotics are a crucial tool in the fight against bacterial infections, both in humans and animals. However, inappropriate use of these drugs has led to bacteria adapting and developing resistance to them, as is the case of P. aeruginosa bacteria, which has multiple ways of resisting even last-line antibiotics, such as colistin. This antimicrobial polypeptide is effective against gram-negative bacteria, but it has nephrotoxic side effects and its efficacy is decreasing against P. aeruginosa. To address this global problem, new techniques have been developed to improve the antimicrobial activity of existing antibiotics. One such technique is the encapsulation of colistin in a natural polymer called chitosan, which improves drug dispersion and increases its activity against bacteria. Recent studies evaluated the performance of chitosan nanoparticles loaded with antibiotics to treat bacterial resistance. The results indicated a significant decrease in bacterial antimicrobial activity, suggesting that the chitosan encapsulation technique could be a promising alternative for the treatment of antibiotic-resistant bacterial infections. To determine this, the performance of chitosan nanoparticles loaded with colistin was synthesized, characterized and evaluated against 2 strains of P. aeruginosa, one sensitive and the other extremely resistant to colistin; obtaining as a result a decrease in the microbial activity (going from growth at colistin concentration of 16 µ/mL to 4 µ/mL) of extremely resistant P. aeruginosa
Síntesis de nanopartículas poliméricas asociadas a imipenem para enfrentar la multidrogorresistencia frente a la bacteria Klebsiella pneumoniae productora de carbapenemasas tipo KPC
(Universidad Santiago de Cali, 2023) Bautista Rincón, Angibet; Chalarca Salazar, Angie Yuliet; Oñate Garzón, José Fernando; Rivera, Sandra Patricia
Klebsiella pneumoniae is a Gram negative bacterium and is the main Enterobacterium isolated in hospital infections, since it plays an important role in nosocomial diseases. Klebsiella pneumoniae is becoming a public health problem worldwide because it has a type of enzyme called KPC-type carbapenemase that gives the bacteria resistance to carbapenem drugs such as Imipenem, Meropenem, Ertapenem and Doripenem. Imipenem is an antibiotic that is supplied in combination with another drug called cilastatin, which helps to prolong the effect of imipenem by protecting it from breakdown when ingested [1], however, the administration of this type of drug generates side effects. in patients becoming nephrotoxic. One of the promising strategies to combat resistant bacteria, decrease the rate of morbidity and mortality from nosocomial infections, and reduce the side effects generated by the administration of certain antibiotics, is the use of antibiotic-loaded chitosan nanoparticles. Chitosan is a biopolymer that is obtained from the partial deacetylation of chitin which is present in the exoskeleton of crustaceans. Due to the high biocompatibility of chitosan, it is currently used as a material for the production of nanoparticles. Chitosan nanoparticles have high potential for the loading, transport and controlled release of molecules [2]. The purpose of this study is to develop polymeric chitosan nanoparticles associated with imipenem to face the bacterial resistance of Klebsiella pneumoniae. The method consists of the production and characterization of highly deacetylated chitosan and imipenem-loaded chitosan nanoparticles obtained by ionic gelation assisted by high intensity sonication. These nanoparticles were analyzed and characterized in terms of particle size, Polydispersity Index, Potential Zeta (PZ) and encapsulation efficiency. Its antimicrobial activity was evaluated using the broth microdilution method according to the Clinical & Laboratory Standards Institute (CLSI) using carbapenem-sensitive and resistant Klebsiella pneumoniae strains. As a result, a particle size < 500 nm, positive Zeta potential values and a stable polydispersity index with values between 0.07 and 0.2 were obtained, obtaining a monodisperse population. The reported results were promising for Klebsiella pneumoniae demonstrating that imipenem-loaded chitosan nanosystems provided antibacterial efficacy compared to free imipenem against Gram-negative bacteria resistant to this antibiotic

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Browsing Microbiología by Subject "Actividad Antimicrobiana"

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