EL DIÓXIDO DE CARBONO MODIFICA LA ACTIVIDAD ANTIMICROBIANA DE CIPROFLOXACINA Y LA GENERACIÓN DE ESTRÉS OXIDATIVO EN Escherichia coli

V CANO ARISTIZÁBAL, MA QUINTEROS, MG PARAJE, PL PÁEZ.

Asunción

Jornada; XXV Jornadas de Jóvenes Investigadores AUGM 2017; 2017

Organizado por la asociación de universidades grupo Montevideo y la universidad de Itapúa

Oxidative stress is defined as an imbalance betweenoxidants and antioxidants substances. Several compounds, including antibiotics,are capable of generating oxidative stress in bacteria. The aim of this workwas contribute to the understanding of action mechanism of ciprofloxacin (CIP) asgenerator of oxidative damage in Escherichiacoli by assessing oxidative stress in controlled atmospheres of CO2to evaluate their potential implications for human health. We determined theproduction of reactive oxygen species (ROS) mediated by CIP under two differentconditions of CO2 (50 and 50.000 ppm) by spectrofluorometry using H2-DCFDAas fluorescent probe in Escherichia coliATCC 25922. The ferrous reduction antioxidant potency (FRAP), SOD, CAT and GSHwere studied by spectrophotometry. It was observed that CO2 modifies CIP antibacterial activityagainst E. coli. CIP 0.5 µg/mL showeda reduction of 2 log10 in bactericidal effect for the two conditionstested of CO2. At lower concentration of CO2 (50 ppm),ROS production increases until 2 h 20.1 and 40.8 % with CIP 0.5 and 50 µg/mL;respectively. At higher concentration of CO2 (50.000 ppm), CIP 0.5 µg/mLgenerates a greater increase in ROS (26.2 %) than 50 µg/mL (14.6 %). Underatmospheric conditions and in the absence of CIP, an increase of the enzymaticand non-enzymatic antioxidant systems could be observed. As the concentrationof CIP and CO2 increased, a consumption of all the antioxidantsystems tested could be observed. This behavior observed in differentconditions of CO2 indicates that the activity of CIP mediated by ROSgeneration is modified not only by the presence of CO2, also by itsconcentration.