In this study, it can be concluded that: Cinnamaldehyde and
carvacrol not only exhibit high antibacterial activities and have
concentration (FIC) index which was combined with the
checkerboard method (Pei, Zhou, Ji, & Xu, 2009) for each combination
using the following formula. The FIC was used to interpret
the test results as follows: FIC 0.5, synergy; FIC ¼ 0.5e4, no
synergistic antimicrobial activities at least for most of the test
bacteria, but also are safe as food preservatives. The results indicated
that cinnamaldehyde and carvacrol may serve as promising
naturally sourced composite food preservatives. Additionally,
further studies are needed to investigate the mechanism and
relationship between the antibacterial activity and chemical
structure of cinnamaldehyde and carvacrol