- 143298
Apresentação de Pôster
Favoritar este trabalho
Como citar esse trabalho?

Dermatophytoses are mycoses that affect the skin and its appendages, caused by keratinophilic fungi, with contagion occurring mainly through direct contact with infected humans, animals or exposure to contaminated soil. Relapses due to interruption of antifungal therapy have often been associated with dermatophytosis, increasing the incidence of antifungal resistance to available drugs, requiring the development of new antifungals and evaluation of their efficacy and toxicity. Nanoparticles are particles reduced to a nanometric scale, and with that, several physical, chemical and biological properties are altered. The use of metallic nanoparticles in clinical practice has been shown to be efficient due to their antimicrobial activity. Among the various processes of synthesis of metal nanoparticles, there are physical, chemical and biological methods. Biosynthesis occurs through enzyme-mediated reduction/oxidation reactions that act on various compounds to form nanoparticles, making fungi efficient at producing these nano-sized materials due to high enzyme secretion. The objective of this work was to synthesize silver nanoparticles (AgNPs) by a strain of Lichtheimia ornata and to evaluate the antimicrobial potential against the dermatophyte fungi Trichophyton rubrum and Microsporum gypseum. For production, the strain of L. ornata was cultivated in malt agar added with yeast extract. For the characterization of AgNPs, UV – Vis, FTIR, zeta potential, DLS and EDXRF methods were used. The MET of the AgNPs produced was performed to evidence their morphology and cluster formation. To assess the antimicrobial potential, broth microdilution tests were performed to obtain minimum inhibitory concentration (MIC) and minimum fungicidal concentration (MFC). Production monitoring was confirmed by peak formation in the 420 nm region. The particles had infrared spectral peaks of 3460 nm, 2370 nm and 1637 nm. In relation to the zeta potential, a surface charge of -17.9 mV was obtained, demonstrating stability. Regarding size, an average size of 93.8 nm, and spherical shape were observed. The concentration of AgNPs obtained was 6.3 mM. The MIC values for T. rubrum and M. gypseum were 2.65 μg/mL and 5.31 μg /mL, respectively. AgNPs showed fungicidal activity against T. rubrum, with MFC of 5.31 μg /mL and fungistatic activity against M. gypseum. Thus, AgNPs produced by L. ornata showed promising antifungal potential in the treatment of dermatophytoses caused by the microorganisms evaluated in in vitro tests. The continuity of the work is necessary in order to carry out tests using other dermatophyte species, and in-depth studies for the incorporation of AgNPs into a commercially viable product.

  • 1 Universidade Estadual de Londrina
  • 2 Departamento de Microbiologia / Centro de Ciências Biológicas / Universidade Estadual de Londrina
  • 3 Universidade Federal do Paraná
Eixo Temático
  • Inovação e Biotecnologia
Metallic nanoparticles;
Microsporum gypseum
Antimicrobial activity