Peng Liying, Chen Zongtao, Hei Yanting, Wei Wenyan, Chen Defang
Department of Aquaculture, College of Animal Science and Technology, Sichuan Agricultural University, Chengdu, China.
Institute of Fisheries Research, Chengdu Academy of Agricultural and Forestry Sciences, Chengdu, China.
Foodborne Pathog Dis. 2025 Jun;22(6):422-429. doi: 10.1089/fpd.2024.0072. Epub 2024 Oct 9.
The emergence of Motile Aeromonas Septicemia (MAS) caused by in sturgeon farming has become a significant concern due to its high mortality impact on the aquaculture industry. The threat posed by MAS highlights the urgent need for effective control measures to combat bacterial infections in sturgeon populations. Tea polyphenol (TP) has demonstrated promising antibacterial properties against livestock and poultry bacterial infections. However, its antibacterial efficacy and mechanism in bacterial diseases of aquatic animals remain largely unexplored. This study aimed to investigate the antibacterial effect and mechanism of TP on fish-borne drug-resistant TH0426 by assessing the impact of TP on TH0426 cell growth, antibiofilm activity, morphology, as well as measuring electrical conductivity, DNA extravasation, lactate dehydrogenase (LDH) activity, protein, and DNA contents. Results demonstrated that the minimum inhibitory concentration and the minimum bactericidal concentration of TP on TH0426 were 1024 and 2048 μg/mL, respectively. After a 4 h treatment, the growth of TH0426 was completely inhibited at the concentration of 1024 and 2048 μg/mL of TP. Meanwhile, TP exhibited a significant antibiofilm activity. Both scanning electron microscope and transmission electron microscope analyses revealed disrupted cell membrane structure, irregular cell morphology, and loss of intracellular contents following TP treatment. Moreover, increased cell membrane permeability induced by TP led to intracellular ion and DNA leakage, resulting in elevated electrical conductivity and DNA extravasation. Furthermore, TP decreased LDH activity, protein concentration and content, DNA fluorescence intensity, and density in a time-dependent manner, indicating inhibition of protein metabolism and DNA synthesis. In conclusion, TP exhibits potent antibacterial properties by inhibiting biofilm formation, disrupting cell membrane integrity, and interfering with protein metabolism and DNA synthesis in drug-resistant TH0426 .
在鲟鱼养殖中，由嗜水气单胞菌引起的运动性气单胞菌败血症（MAS）的出现，因其对水产养殖业的高死亡率影响而成为一个重大问题。MAS构成的威胁凸显了采取有效控制措施以对抗鲟鱼种群细菌感染的迫切需求。茶多酚（TP）已显示出对畜禽细菌感染具有有前景的抗菌特性。然而，其在水生动物细菌性疾病中的抗菌效果和机制在很大程度上仍未得到探索。本研究旨在通过评估TP对TH0426细胞生长、抗生物膜活性、形态的影响，以及测量电导率、DNA外渗、乳酸脱氢酶（LDH）活性、蛋白质和DNA含量，来研究TP对鱼源耐药菌TH0426的抗菌作用及其机制。结果表明，TP对TH0426的最小抑菌浓度和最小杀菌浓度分别为1024和2048μg/mL。经过4小时处理后，在TP浓度为1024和2048μg/mL时，TH0426的生长被完全抑制。同时，TP表现出显著的抗生物膜活性。扫描电子显微镜和透射电子显微镜分析均显示，TP处理后细胞膜结构破坏、细胞形态不规则以及细胞内物质流失。此外，TP诱导的细胞膜通透性增加导致细胞内离子和DNA泄漏，从而使电导率和DNA外渗升高。此外，TP以时间依赖性方式降低LDH活性、蛋白质浓度和含量、DNA荧光强度以及密度，表明对蛋白质代谢和DNA合成有抑制作用。总之，TP通过抑制生物膜形成、破坏细胞膜完整性以及干扰耐药菌TH0426的蛋白质代谢和DNA合成而表现出强大的抗菌特性。
