Reactive Oxygen Species Production from Hydroxamic Acid and their Iron (III) Complexes against Staphylococcus aureus and Escherichia coli

Abstract

The N-hydroxydodecanamide (HA12) and its complexes tri-hydroxamato-iron(III) and di-hydroxamto-iron(III) chloride (HA8Fe3 and HA12Fe3Cl, respectively) showed antibacterial and antimycobacterial activities. The proteomic analysis demonstrated that the targets of Hydroxamic Acid (HA) and their complexes were involved in the biosynthesis of mycobacterial cell walls. The Reactive Oxygen Species (ROS) is one of the key elements to cause oxidative stress, damaging DNA, and cell membranes impaired during the procedure to kill bacteria. Here, the ROS production was determined to evaluate the compounds HA12, HA8Fe3, HA12Fe3Cl, and ZnCl2 against bacteria using 2’,7’-dichlorofluorescein diacetate (DCFDA) by spectrofluorometric analysis. The low fluorescence was observed using the compounds HA12, HA8Fe3, HA12Fe3Cl, and ZnCl2 treating the S. aureus and E. coli, indicating that the ROS production could be observed using the compounds used at a dose higher than the Minimum Inhibitory Concentration (MIC). It was noted that the ROS determination could be performed with a concentration less than or equal to the MIC. This would enable the mechanism of action linked to the ROS production by HA and their metal complexes to be determined.