We evaluated the bactericidal efficacy of the simultaneous application of ultraviolet-A (UV-A) irradiation and fumaric acid (FA) against Escherichia coli O157:H7, Salmonella enterica serovar Typhimurium, and Listeria monocytogenes in apple juice and as well as investigated the effects of this treatment on product quality. Further, we elucidated the mechanisms underlying their synergistic bactericidal action. Simultaneous UV-A light irradiation and 0.1% FA treatment for 30 min resulted in 6.65-, 6.27-, and 6.49-log CFU/ml reductions in E. coli O157:H7, S. Typhimurium, and L. monocytogenes, respectively, which involved 3.15, 2.21, and 3.43 log CFU reductions, respectively, and these were attributed to the synergistic action of the combined treatments. Mechanistic investigations suggested that the combined UVA-FA treatment resulted in significantly greater bacterial cell membrane damage and intracellular reactive oxygen species (ROS) generation. UVA-FA treatment for 30 min did not cause significant changes to the color, nonenzymatic browning index, pH, and total phenolic content of apple juice. These results suggest that combined UVA-FA treatment can be effectively used to control foodborne pathogens in apple juice without affecting its quality.

中文翻译：

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通过富马酸和紫外线-A光联合处理灭活苹果汁中食源性病原体及其协同杀菌作用的机制。

我们评估了同时应用紫外线-A（UV-A）照射和富马酸（FA）对苹果汁中的大肠杆菌O157：H7，肠炎沙门氏菌血清型鼠伤寒杆菌和单核细胞增生性李斯特菌的杀菌功效，并研究了其效果处理对产品质量的影响。此外，我们阐明了其协同杀菌作用的机制。同时进行30分钟的UV-A光照射和0.1％FA处理导致大肠杆菌O157：H7，鼠伤寒沙门氏菌和单核细胞增生李斯特菌的CFU / ml降低了6.65、6.27和6.49 log log / fu。分别导致CFU降低3.15、2.21和3.43，这归因于联合治疗的协同作用。机理研究表明，UVA-FA联合处理导致细菌细胞膜损伤和细胞内活性氧（ROS）的产生显着增加。UVA-FA处理30分钟并没有引起苹果汁的颜色，非酶褐变指数，pH和总酚含量的显着变化。这些结果表明，UVA-FA联合处理可以有效地控制苹果汁中食源性病原体，而不会影响其质量。