HNU-HSF Collaborative Innovation Laboratory, College of Food Sciences & Engineering, Hainan University, 58 People Road, Haikou 570228, PR China.
HNU-HSF Collaborative Innovation Laboratory, College of Food Sciences & Engineering, Hainan University, 58 People Road, Haikou 570228, PR China; Chunguang Agro-product processing institute, Wenchang 571333, China.
Food Res Int. 2022 Jul;157:111407. doi: 10.1016/j.foodres.2022.111407. Epub 2022 May 25.
This work aimed to explore the antibacterial ability and potential mechanism of linalool against Brochothrix thermosphacta (B. thermosphacta), providing knowledge of the preservation of chilled beef with linalool. The results found that linalool had an encouraging inhibitory effect on B. thermosphacta with a minimum inhibitory concentration (MIC) of 1.5 mL/L. Results of FESEM and zeta potential combined with probe labeling confirmed that linalool destroyed the cell structure thereby causing the leakage of intracellular components (AKP, protein, nucleic acid and ion). In addition, linalool caused respiratory disturbance by measuring the key enzyme activities including PK, SDH, MDH and ATPase. Energy limitation also appeared under linalool stress as seen from changes in ATP content (decreased by 56.06% and 69.24% in MIC and 2MIC groups, respectively). The respiratory inhibition rate of linalool to B. thermosphacta was 23.58% and the superposing rate with malonic acid was minimal (35.52%), suggesting that respiratory depression was mainly caused by the TCA cycle. Furthermore, accumulation of ROS and increase in MDA content (increased by 71.17% and 78.03% in MIC and 2MIC groups, respectively) accompanied by decreased activities of detoxification enzymes CAT and POD suggested that oxidative stress contributed to the bactericidal mechanism. Finally, linalool has been shown to effectively inhibit quality deterioration of chilled beef during storage by measuring pH, TVB-N and TVC without affecting sensory acceptability. All these highlight the great promise of using linalool as natural preservative for food industry.
本研究旨在探索芳樟醇对热杀索丝菌（B. thermosphacta）的抗菌能力及其潜在机制，为利用芳樟醇保鲜冷却牛肉提供理论依据。结果表明，芳樟醇对 B. thermosphacta 具有良好的抑制作用，其最小抑菌浓度（MIC）为 1.5ml/L。FESEM 和 ζ 电位结合探针标记结果证实，芳樟醇破坏了细胞结构，导致细胞内成分（AKP、蛋白质、核酸和离子）泄漏。此外，通过测量关键酶活性（PK、SDH、MDH 和 ATPase），发现芳樟醇引起了呼吸紊乱。在芳樟醇胁迫下，还出现了能量限制，表现为 ATP 含量的变化（MIC 和 2MIC 组分别下降了 56.06%和 69.24%）。芳樟醇对 B. thermosphacta 的呼吸抑制率为 23.58%，与丙二酸的叠加率最低（分别为 35.52%），表明呼吸抑制主要是由 TCA 循环引起的。此外，ROS 积累和 MDA 含量增加（MIC 和 2MIC 组分别增加了 71.17%和 78.03%），同时解毒酶 CAT 和 POD 的活性降低，表明氧化应激参与了杀菌机制。最后，通过测量 pH 值、TVB-N 和 TVC，发现芳樟醇在不影响感官可接受性的情况下，能有效抑制冷却牛肉在贮藏过程中的品质劣变。综上所述，芳樟醇有望作为一种天然防腐剂应用于食品工业。
