Lee In-Hwan, Kim Soo-Hwan, Kang Dong-Hyun
Department of Agricultural Biotechnology, Center of Food and Bioconvergence, Research Institute of Agriculture and Life Sciences, Seoul National University, Seoul, 08826, Republic of Korea.
Institutes of Green Bio Science and Technology, Seoul National University, Pyeong-Chang, Gangwon-do, 25354, Republic of Korea.
Curr Res Food Sci. 2022 Dec 30;6:100428. doi: 10.1016/j.crfs.2022.100428. eCollection 2023.
Interest in using an antimicrobial photodynamic treatment (aPDT) for the microbial decontamination of food has been growing. In this study, quercetin, a substance found ubiquitously in plants, was used as a novel exogenous photosensitizer with 405 nm blue light (BL) for the aPDT on foodborne pathogens, and the inactivation mechanism was elucidated. The inactivation of O157:H7 and in PBS solution by the quercetin and BL combination treatment reached a log reduction of 6.2 and more than 7.55 at 80 J/cm (68 min 21 s), respectively. When EDTA was added to investigate the reason for different resistance between two bacteria, the effect of aPDT was enhanced against O157:H7 but not . This result indicated that the lipopolysaccharide of Gram-negative bacteria operated as a protective barrier. It was experimentally demonstrated that quercetin generated the superoxide anion and hydrogen peroxide as the reactive oxygen species that oxidize and inactivate cell components. The damage to the bacterial cell membrane by aPDT was evaluated by propidium iodide, where the membrane integrity significantly ( < 0.05) decreased from 40 J/cm compared to control. In addition, DNA integrity of bacteria was significantly ( < 0.05) more decreased after aPDT than BL treatment. The inactivation results could be applied in liquid food industries for decontamination of foodborne pathogens, and the mechanisms data was potentially utilized for further studies about aPDT using quercetin.
使用抗菌光动力疗法（aPDT）对食品进行微生物去污处理的关注度一直在不断提高。在本研究中，槲皮素这种在植物中普遍存在的物质，被用作一种新型的外源性光敏剂，结合405纳米蓝光（BL）对食源性病原体进行aPDT处理，并阐明了其灭活机制。在80 J/cm²（68分21秒）时，槲皮素与蓝光联合处理对磷酸盐缓冲盐溶液（PBS）中的O157:H7和的灭活对数减少量分别达到6.2和超过7.55。当添加乙二胺四乙酸（EDTA）以探究两种细菌耐药性差异的原因时，aPDT对O157:H7的效果增强，但对则不然。这一结果表明革兰氏阴性菌的脂多糖起到了保护屏障的作用。实验证明，槲皮素产生超氧阴离子和过氧化氢作为活性氧物种，氧化并使细胞成分失活。通过碘化丙啶评估aPDT对细菌细胞膜的损伤，与对照组相比，在40 J/cm²时膜完整性显著（P < 0.05）降低。此外，aPDT处理后细菌的DNA完整性比蓝光处理后显著（P < 0.05）降低更多。灭活结果可应用于液体食品工业中食源性病原体的去污处理，而这些机制数据有可能用于关于使用槲皮素的aPDT的进一步研究。
