A Susceptibility Screen of Phytochemicals Against Staphylococcus aureus

Abstract

Given the current and emerging levels of bacterial resistance to existing antimicrobic agents, evaluative assessment of plant‐derived compounds for antibacterial potential was deemed important and timely. The focus of this research was to determine the effect of phytochemicals on Staphylococcus aureus using the Kirby‐Bauer susceptibility assay, a method widely used in clinical laboratories as standard operating procedure for determination of bacterial susceptibility to antibiotics. Whatman filter disks were saturated with phytochemical and placed onto a Mueller Hinton agar plate swabbed with bacteria using the standard 3‐way streak method. Bacterial plates were incubated and then susceptibility was determined by measurement of resultant zones of inhibition. Antibiotic disks were assessed in parallel with phytochemical‐impregnated disks. The hypothesis was that specific phytochemicals inhibit bacterial growth. S. aureus (n=4 ATCC strains) displayed large zones of inhibition for cinnamaldehyde (31±12 mm: mean±SD), epigallocatechin gallate (14±1 mm) and plumbagin (16±3 mm). Inclusion of cinnamaldehyde, epigallocatechin gallate or plumbagin as anti‐Staphylococcus agents as direct therapeutic agents or as combination treatment strategies with current antimicrobial drugs may offer treatment options for patients with multi‐drug resistant bacterial infections.Support or Funding InformationFinancial support for VPM was received from the DeNardo Education and Research Foundation.This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.