Synergistic antimicrobial effects of allyl isothiocyanate and cinnamaldehyde on Pseudomonas fluorescens and their application in chilled beef

In this study, the synergistic antimicrobial effect of allyl isothiocyanate (AITC) and cinnamaldehyde (CAL) against Pseudomonas fluorescens ( P. fluorescens ) was investigated. The fractional inhibitory concentration index (FICI) value of 0.5 in the combination of AITC and CAL indicated the synergistic effect on P. fluorescens by reducing their dosages. Compared with the individual AITC and CAL, the combined treatment group increased protein leakage concentration and intracellular reactive oxygen species content, as well as significantly inhibited the motility of P. fluorescens ( P < 0.05), with a reduction of 6.3 and 10.3 mm in swimming diameter, respectively. Meanwhile, this combination resulted in a 93.4 % reduction in biofilm formation compared to the untreated group. Moreover, combined treatment with AITC and CAL significantly inhibited the growth of P. fluorescens and delayed the increase of total volatile base nitrogen in chilled beef. Therefore, this study provides a reference for the application of a combination of AITC and CAL for beef preservation.