苍耳叶提取物与生物抑菌剂对几种常见食品污染菌的体外协同抑菌作用及其作用机理

Synergistic mechanism of Xanthium sibiricum leaf and biological antimicrobial agents against several common microorganisms causing food contamination

测定了苍耳叶乙醇提取物和3种生物抑菌剂(ε-聚赖氨酸、乳酸链球菌素和纳他霉素)对6种常见食品污染菌的抑菌效果;分析了苍耳叶乙醇提取物与生物抑菌剂联用时的协同抑菌效果(FICI值)。结果表明,联用组对不同菌株表现出协同或者相加抑菌效果,其中苍耳叶乙醇提取物与纳他霉素联用对扩展青霉协同作用显著(FICI=0.375),这种协同作用的机理可能是通过增强菌体细胞膜透性,促进纳他霉素渗透入菌体,增加有效浓度累积,造成细胞膜的破裂,导致菌体死亡。

Ethanol extracts of Xanthium sibiricum leaf and three biological antimicrobial agents （ ε-poly lysine, nisin and natamycin） were investigated for their single and combined antibacterial activities against six common pathogenic microorganisms. Results showed that the combined treatments revealed remarkable synergistic and/or additive antibacterial activities against these six pathogens. Among them, the ethanol extracts of Xanthium sibiricum leaf and natamycin exhibited the strongest synergistic interaction in inhibiting Penicillium expansum （FIC1 = 0. 375）. Furthermore, this mechanism of antibacterial synergism might be attributed to their ability to enhance the permeability of cell membrane, and thereby facilitate the penetration and effective accumulation of natamycin in the bacteria,then cause the rupture of cell membrane, finally lead to the death of bacteria.