Lycopene for wound infection: In-vitro susceptibility of drug-resistant clinical pathogens

Abstract

Wound infections caused by drug-resistant pathogens have limited treatment options, consequently the need to screen new antimicrobials. Phytochemicals have been adopted as sources for new antimicrobials. Consequently, the study aimed to estimate the antibacterial activity of lycopene phytochemical against drug-resistant wound pathogens: Staphylococcus aureus, Escherichia coli, Proteus mirabilis, Pseudomonas aeruginosa and Klebsiella pneumoniae. The antibiotic susceptibility profiles of all the resistant clinical isolates to commonly administered antibiotics were determined using disc diffusion method. The drug-resistant Gram-negative and Gram-positive bacteria (both groups) isolated from infected wounds were investigated for their in-vitro susceptibility to the lycopene extracted from tomato (Lycopersicon esculentum) by agar-well diffusion assay and broth dilution method. Differences of mean zone of inhibitions (ZOIs), minimum inhibitory concentrations (MICs) and minimum bactericidal concentrations (MBCs) values among the drug-resistant wound isolates were considered significant where P ˂ 0.05. All isolates were resistant to Augmentin, Gentamicin, Ciprofloxacin and Streptomycin. In-vitro susceptibility to lycopene revealed the mean and standard deviation of the ZOIs for all isolates as 7.6 ± 3.49 mm. The studied lycopene showed bactericidal effects against all the drug-resistant bacteria tested. The MICs and MBCs of the wound isolates ranged from 50 and 125 μg/mL. The difference between the mean ZOIs, MICs/MBCs of both groups were not significant. This study demonstrated that lycopene has antibacterial activity against some drug-resistant wound isolates thus, offers a good alternative to existing treatment options for wound infections.