Direct and indirect antimicrobial effects of α-mangostin on pathogenic microorganisms

Objective:To test direct and indirect antimicrobial properties of α-mangostin towards a number of bacteria and fungi.Methods:Activity of α-mangostin paired with an antibiotic was studied by calculating its fractional inhibitory concentration(FIC).Results:The experiment was carried out using broth microdilution and checkerboards methods.tetracycline showed no interaction with the combination withα-mangostin where the FIC indexes were between the range of 0.5<FIC_(index)>4.Activity of doxycycline on Pseudomonas aeruginosa fell into other set of range,FIC_(index)≥4 which is an antagonism.The activity of all four bacteria towards ampicillin,penicillin G,streptomycin and Conclusions:The FIC index is far away in the range.The coupled antibiotic andα-mangostin is considered synergy in action if it lies in FIC_(index)≤0.5 and it was found that the isolated compound,α-mangostin revealed very low synergistic antimicrobial effects when coupled with antibiotics.