Determinación de la actividad antimicrobiana y antioxidante de los extractos de la planta sunfo (Clinopodium nubigenum) frente a cepas de Staphylococcus

Abstract

Foodsborne illnesses cause symptoms such as: diarrehea, vomiting and stomach pains; the treatment is the use of antibiotics such as: cephalosporins, penicillin and aminoglycosides. Due to the bad use, resistance has occurred to bacteria such as: E. coli, L. monocytogenes, S. aureus, among others. In the present investigation, the bacteria used was S. aureus and Coagulase Negative Staphylococcus (CoNS), obtained in cheeses from markets in the City of Ambato, where searched for an alternative to the use of antibiotics through antimicrobial tests and its relationship with the antioxidant activity. For this purpose, an extract of the Sunfo (C. nubigenum) was obtained, where its main components are polyphenols such as: flavonoids and phenolic acids. Through the Soxhlet method, secondary metabolites were obtained together with the solvent ethanol. The identification of the bacteria was realized on Salted Mannitol Agar, a yellow colour indicated the presence of S. aureus and a red colour indicated the presence of CoNS. For the antimicrobial test, the Minimum Inhibitory Concentration (MIC) and Bactericidal Concentration (MBC) were used together with the resazurin indicator, observing a change in coloration; for antioxidant activity, a colorimetric assay was realized with 2,2-diphenyl-1-picrylhydrazyl (DPPH). Finally, it was determined that the C. nubigenum extract presented antimicrobial properties, due to the inhibition of the S. aureus and CoNS species, verifying the colour change with the MIC and MBC test. Likewise, the evaluated extract presented antioxidant properties by reading absorbances between DPPH and the extract.