肉桂精油纳米乳的制备及抗菌活性研究

Preparation and Antibacterial Activity of Cinnamon Essential Oil Nanoemulsion

肉桂精油具有良好的抗菌和抗氧化特性,由于存在挥发性强、水溶性差等问题,制约了其在食品保鲜领域的应用。研究证实,纳米乳化技术能够有效提高精油的水溶性及稳定性。文章以壳聚糖与果胶为壁材制备肉桂精油纳米乳(cinnamon essential oil nanoemulsion,CON),并评价了其抗菌活性。结果表明,超声波法制备CON的最优参数:肉桂精油添加量为1%~2%,壳聚糖与果胶的体积比为1∶1,超声波处理时间为7.5 min,超声波功率为450 W;制备的纳米乳粒径分布在10~150 nm,分散性及稳定性最好;CON对大肠杆菌O157:H7(Escherichia coli O157:H7)、单增李斯特菌(Listeria monocytogenes)和假单胞菌CM2(P.deceptionensis CM2)的最小抑菌浓度分别为0.500,0.250,0.125μL/mL,表明CON具有较好的抑菌活性。该研究结果将为CON在食品保鲜中的应用提供理论依据和技术支撑。

Cinnamon essential oil has excellent antibacterial and antioxidant properties.The application of cinnamon essential oil in the field of food preservation is restricted because of its strong volatility and poor water solubility.Studies have confirmed that nano emulsification technology could effectively improve the water solubility and stability of essential oil.In this paper,cinnamon essential oil nanoemulsion(CON) is prepared with chitosan and pectin as the wall materials,and its antibacterial activity is evaluated.The results show that the optimal parameters for preparing CON by ultrasonic method are as follows:the addition amount of cinnamon essential oil is 1%~2%,the volume ratio of chitosan to pectin is 1∶1,the ultrasonic treatment time is 7.5 min,and the ultrasonic power is 450 W.The particle size distribution of the prepared nanoemulsion is 10~150 nm with the best dispersivity and stability.The minimum inhibitory concentrations of CON against Escherichia coli O157:H7,Listeria monocytogenes and P.deceptionensis CM2 are 0.500,0.250,0.125 μL/mL respectively,indicating that CON has good antibacterial activity.The results will provide theoretical basis and technical support for the application of CON in food preservation.