复合生物保鲜剂对金黄色葡萄球菌的抑菌作用研究

研究了壳聚糖、溶菌酶与茶多酚配制而成的复合保鲜剂对金黄色葡萄球菌的抑菌作用。采用琼脂平板打孔法确定复合保鲜剂对金黄色葡萄球菌的最小抑菌浓度(MIC)与最小杀菌浓度(MBC),结合抑菌率、抑菌活力、细菌生长曲线、膜完整性、AKP活性与细菌超微结构,综合评价复合保鲜剂对金黄色葡萄球菌的影响。结果得出,复合保鲜剂对金黄色葡萄球菌的MIC与MBC分别为0.8 mg/mL与1.6 mg/mL,随着作用时间的延长,复合保鲜剂对金黄色葡萄球菌的生长抑制明显,菌体的细胞壁与细胞膜完整性受到破坏,菌体细胞中的AKP量增多,影响菌体细胞的代谢循环,菌体内部的核酸与蛋白质外泄,抑制其正常生长。由细菌超微结构观察发现,菌体细胞经复合保鲜剂处理后,造成菌体扭曲变形,细胞壁破裂,细胞质外渗。表明复合保鲜剂可破坏菌体的细胞壁,影响胞膜稳定性与胞内环境,最终导致菌体死亡。

Antibacterial Effect of Composite Natural Preservatives Against Staphylococcus aureus

In this paper, antibacterial activity of composite natural preservatives with chitosan, lysozyme, and tea polyphenols against Staphylococcus aureus were investigated. Minimal inhibitory concentration(MIC) and minimal bactericidal concentration(MBC) of composite natural preservatives were determined by stiletto method. The damage of Staphylococcus aureus which treated with composite natural preservatives were studied by cell damage experiment, such as bacteriostatic rate, antibacterial kinetics, growth curve, integrity of cell membrane, alkaline phosphatase(AKP) activity and ultra microstructure of bacteria. It concluded that the MIC and MBC of composite natural preservatives were 0.8mg/mL and 1.6mg/mL. With the extension of time, composite natural preservatives could inhibit the growth of Staphylococcus aureus, increase the quantity of AKP, and destroy the metabolic circulation, make the nucleic acid and protein leaked in cells. When treated with composite natural preservatives, Staphylococcus aureus was distorted, the cell wall was ruptured, the cytoplasm was spilled out, the stability of cell membrane and intracellular environment was destroyed, which led to the death of Staphylococcus aureus.