In vitro Antibacterial Activity of Blue Vitriol and Alum against Superficial Surgical Site Infection Pathogens

Abstract

Surgical site infection (SSI) is a threat to global health security. The unending search and demand for effective, non-toxic and readily available raw materials to treat surgical site infections is ineluctable. The study aimed at assessing the in vitro antibacterial activity of blue vitriol and alum against superficial surgical site infection pathogens. Seventy surgical wound swab specimens were aseptically and carefully collected from patients with superficial surgical wounds after abdominal surgery at a University Teaching Hospital in Southeastern Nigeria. The bacteria isolates were identified based on their morphological, physiological, biochemical and molecular characteristics. The antimicrobial activity of blue vitriol and alum was determined using the agar-well diffusion method; while their minimal inhibitory and bactericidal concentrations against the isolates were determined using the broth dilution method. The isolates include Staphylococcus xylosus, Pseudomonas aeruginosa, Staphylococcus aureus and Escherichia coli. The isolates showed varying sensitivity patterns to the test antimicrobials. The inhibition zones diameter (IZD) of the samples vary with concentration. Blue vitriol (200 mg/ml) gave the best inhibition (IZD 27.50±3.54 mm) against Staphylococcus aureus; while alum (200 mg/ml) exhibited the highest inhibition (IZD 25.00±0.00 mm) against Pseudomonas aeruginosa. The least inhibition was observed at 25 mg/ml; while no inhibition was observed at 12.5 mg/ml. Alum and blue vitriol exhibited similar MIC and MBC values (25 mg/ml) against all the isolates, though levofloxacin (positive control) gave a better MBC value of 12.5 mg/ml against all the isolates except E. coli (25 mg/ml). The study revealed that alum and blue vitriol showed good inhibition in vitro, against all the isolates. If clinically proven, they could serve as good alternative antibacterial agents in managing infections caused by these pathogens, especially surgical site infections.