masterThesis
Avaliação do potencial antimicrobiano e antiparasitário de oligossacarídeos de quitosana
Fecha
2020-07-31Registro en:
SILVA, Nayara Sousa da. Avaliação do potencial antimicrobiano e antiparasitário de oligossacarídeos de quitosana. 2020. 97f. Dissertação (Mestrado em Ciências Farmacêuticas) - Centro de Ciências da Saúde, Universidade Federal do Rio Grande do Norte, Natal, 2020.
Autor
Silva, Nayara Sousa da
Resumen
The increase in outbreaks of infectious diseases, the worldwide progression of
microbial resistance and the high impact of neglected tropical diseases reinforces the
search for new molecules with antimicrobial potential. Chitosan is a copolymer formed
of D-glucosamine and N-acetyl-glucosamine, obtained by partial deacetylation of
chitin. The chitosan hydrolysis generates chitosoligosaccharides (COS) and
monosaccharides. COS have a greater advantage over chitosan due to greater
solubility and lower viscosity. Allied to these parameters, research demonstrates the
vast biological potential of COS with antimicrobial, anti-inflammatory, antioxidant and
anti-tumor properties. Despite the knowledge of the biological effects of COS, the
antiparasitic activity of these molecules is poorly studied. Thus, the objectives of this
study were to obtain COS from the enzymatic hydrolysis of chitosan by chitosanases
from Bacillus toyonensis, to characterize the oligomers and to evaluate their cytotoxic,
antimicrobial and antiparasitic effects in vitro. The mixture of COS produced by
enzymatic hydrolysis in the 5- and 10-min reaction times were characterized by ¹H and
¹³C NMR, uni and bidimensional, and mass spectrometry. Both oligomers evaluated
did not demonstrate cytotoxicity on cancer cells and non-cancer cells up to 2 mg / mL.
The COS revealed an antimicrobial effect similar to chitosan against bacteria and
yeasts. In the antiparasitic assay, the COS showed time-dependent antiparasitic
activity on the Trypanosoma cruzi and Leishmania amazonensis with inhibition rates
of about 30% and above 50%, respectively. The possibility of obtaining a molecule of
high biotechnological interest from shrimp residues, resulting in a decrease in
ecological impact, highlights the importance of the study and use of
chitooligosaccharides to obtain new pharmacological agents.