Gong Chen, Li Yujin, Gao Ruichang, Xiao Feng, Zhou Xiaodong, Wang Haiyan, Xu He, Wang Ruihong, Huang Pan, Zhao Yuanhui
College of Food Science and Engineering, Ocean University of China, 5 Yushan Road, Shinan District, 266003 Qingdao, China.
School of Food and Bioengineering, Jiangsu University, Zhenjiang 212013, Jiangsu, China.
Photodiagnosis Photodyn Ther. 2020 Sep;31:101827. doi: 10.1016/j.pdpdt.2020.101827. Epub 2020 May 21.
The present study aimed to measure the inactivation effect and mechanism of curcumin-mediated photodynamic inactivation (PDI) on the specific spoilage organism (Pseudomonas) of the sturgeon. The conditions of PDI used were as follows: 30 μM curcumin, 15 W LED light (470 nm) power and 90 s irradiation time. Under these conditions, the high-throughput sequencing was used to study the microbiota of sturgeon. The method of aerobic plate colony count (APC) was used to determine the viability of Pseudomonas after PDI. Sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE), the propidium iodide (PI) single staining method, and agarose gel electrophoresis were used to study the inactivation mechanism of PDI on Pseudomonas. The results showed that Pseudomonas was the specific spoilage organism of sturgeon, and PDI significantly inhibited the growth of Pseudomonas. The in-vitro inactivation rate of Pseudomonas was 99.9% with counts decreased by 3.19 ± 0.15 log CFU/mL. The mechanism of PDI to inactivate Pseudomonas is as follows. Firstly, the high-level structure of membrane protein was destroyed, and the cell membrane permeability was increased, which caused leakage of cellular content. Then the nucleic acid inside the cell was destroyed, which eventually caused the death of bacteria. These findings demonstrate that curcumin-mediated PDI can be utilized as an effective way to inactivate the specific spoilage organism (Pseudomonas) of the sturgeon.
本研究旨在测定姜黄素介导的光动力灭活（PDI）对鲟鱼特定腐败菌（假单胞菌）的灭活效果及机制。所用PDI条件如下：30 μM姜黄素、15 W发光二极管灯（470 nm）功率和90 s照射时间。在此条件下，采用高通量测序研究鲟鱼的微生物群。采用好氧平板菌落计数（APC）法测定PDI处理后假单胞菌的活力。利用十二烷基硫酸钠聚丙烯酰胺凝胶电泳（SDS-PAGE）、碘化丙啶（PI）单染法和琼脂糖凝胶电泳研究PDI对假单胞菌的灭活机制。结果表明，假单胞菌是鲟鱼的特定腐败菌，PDI能显著抑制假单胞菌的生长。假单胞菌的体外灭活率为99.9%，菌数减少3.19±0.15 log CFU/mL。PDI灭活假单胞菌的机制如下。首先，膜蛋白的高级结构被破坏，细胞膜通透性增加，导致细胞内容物泄漏。然后细胞内的核酸被破坏，最终导致细菌死亡。这些研究结果表明，姜黄素介导的PDI可作为一种有效方法来灭活鲟鱼的特定腐败菌（假单胞菌）。
