百里香酚和肉桂醛联用对沙门氏菌的协同抑菌效应及其应用

Synergistic Inhibitory Effect of Thymol and Cinnamaldehyde against Salmonella and Applications of the Combination

研究了百里香酚和肉桂醛联用对沙门氏菌的抑菌效果,并将两者作为复配抗菌剂应用于盐焗鸡中以探究其保鲜效果。采用微量稀释法确定了百里香酚和肉桂醛对沙门氏菌的最小抑菌浓度及联合抑菌效果,结果显示百里香酚和肉桂醛的最小抑菌浓度均为0.25 mg/mL、最小杀菌浓度均为0.5 mg/mL;此外,两者联用时的分级抑菌浓度指数为0.75,表明百里香酚和肉桂醛具有较好的协同抑菌效应;该结论同样被时间-杀菌曲线、扫描电子显微镜、PI染色实验的结果所证实,百里香酚和肉桂醛联用可以显著地破坏沙门氏菌细胞膜的完整性,改变细菌形态,从而导致胞内物质泄漏、最终菌体裂解死亡,表明其具有一定的防腐保鲜应用潜力。因此,该研究以盐焗鸡作为食品模型从微生物和脂质氧化两方面探究了百里香酚和肉桂醛的防腐保鲜效果,结果显示百里香酚和肉桂醛联用可以显著地抑制盐焗鸡中细菌的增殖和脂质的氧化,表明百里香酚和肉桂醛联用可以作为一种天然复配抗菌剂应用于盐焗鸡等熟肉制品的保鲜中。

The antibacterial effect of the combined use of thymol and cinnamaldehyde against Salmonella was examined in this study,and the preservation effects of their combinations on salt-baked chickens were also evaluated.The minimum inhibitory concentrations(MICs)and the combined anti-bacterial effect of thymol and cinnamaldehyde against Salmonella were determined by the microdilution method.The results showed that the MICs and minimum bactericidal concentrations(MBCs)of thymol and cinnamaldehyde against Salmonella were 0.25 mg/mL and 0.5 mg/mL,respectively.In addition,the fractional inhibitory concentration index(FICI)of thymol and cinnamaldehyde in combination against Salmonella was 0.75,indicating that the combination of thymol and cinnamaldehyde exhibited a significant synergistic antibacterial effect.The above results were further confirmed by the time-kill curves,SEM analysis and PI staining experiments.That the combined use of thymol and cinnamaldehyde could destroy the integrity of the cell membranes of Salmonella and alter its morphology,causing the leakage of the cell contents and eventually cell lysis and death.These results indicated the potential of the combination as an antiseptic agent and preservative.Therefore,salt-baked chicken was used a model food to examine the antiseptic and preservation effects of thymol and cinnamaldehyde in combination from two aspects,microorganisms and lipid oxidation.The results showed that the combination of thymol and cinnamaldehyde could significantly inhibit the proliferation of bacteria and lipid oxidation in salt-baked chicken.Accordingly,thymol and cinnamaldehyde in combination can be used as a natural compound antibacterial agent for preserving salt-baked chicken and other cooked meat products.