School of Food Science and Engineering, Shaanxi University of Science and Technology, Xi'an 710021, China.
Biofouling. 2023 Feb;39(2):157-170. doi: 10.1080/08927014.2023.2199932. Epub 2023 Apr 11.
Selenium nanoparticles (SeNPs) can be biosynthesized by most Lactic acid bacteria thereby converting toxic sodium into SeNPs. However, few studies have reported the antimicrobial activity of biogenic SeNPs against which are the main species of psychrotrophic bacteria in raw milk. This study reported the synthesis and characterization of SeNPs from ZK-AS 1.1482, and the antimicrobial mechanism against ATCC 13525. The synthesized SeNPs were amorphous with sizes ranging from 52 to 103 nm. Fourier transform infrared spectroscopy (FT-IR) spectra showed the presence of proteins, polysaccharides, and lipids on the surface of particles, which evidently stabilized the SeNPs structure and morphology. Energy-dispersive X-ray (EDX) analysis revealed that the nanoparticles contained selenium. In addition, the minimal inhibitory concentration (MIC) of SeNPs against ATCC 13525 was 0.1 mg ml and the biofilm inhibition rate was 43.52 ± 0.26%. SeNPs decreased the number of living bacteria observed by confocal laser scanning microscopy (CLSM). Meanwhile, after SeNPs treatment, the intracellular adenosine triphosphate (ATP) concentration and antioxidant enzyme activity decreased, the content of reactive oxygen species (ROS) and the malondialdehyde (MDA) content increased, and lipid peroxidation intensified. Real-time fluorescence quantitative PCR (RT-qPCR) assay showed that the expression of , , , , , , , and gene were down-regulated after SeNPs treatment. The and gene were significantly up-regulated, indicating that SeNPs could destroy the integrity of cell membrane and thus play an antimicrobial role. Biogenic SeNPs are expected to be developed as an efficient and novel antimicrobial agent for application in the food industry.
硒纳米粒子（SeNPs）可以被大多数乳酸菌生物合成，从而将有毒的钠转化为 SeNPs。然而，很少有研究报道过生物合成的 SeNPs 对生乳中主要的低温菌的抗菌活性。本研究报道了从 ZK-AS 1.1482 合成和表征 SeNPs，以及其对 ATCC 13525 的抗菌机制。合成的 SeNPs 为无定形，粒径为 52-103nm。傅里叶变换红外光谱（FT-IR）图谱显示，粒子表面存在蛋白质、多糖和脂质，这显然稳定了 SeNPs 的结构和形态。能量色散 X 射线（EDX）分析表明，纳米粒子含有硒。此外，SeNPs 对 ATCC 13525 的最小抑菌浓度（MIC）为 0.1mg/ml，生物膜抑制率为 43.52±0.26%。SeNPs 减少了共聚焦激光扫描显微镜（CLSM）观察到的活菌数量。同时，SeNPs 处理后，细胞内三磷酸腺苷（ATP）浓度和抗氧化酶活性降低，活性氧（ROS）含量和丙二醛（MDA）含量增加，脂质过氧化加剧。实时荧光定量 PCR（RT-qPCR）检测显示，SeNPs 处理后 、 、 、 、 、 、 基因的表达下调。 、 基因显著上调，表明 SeNPs 可以破坏细胞膜的完整性，从而发挥抗菌作用。生物合成的 SeNPs 有望作为一种高效、新颖的抗菌剂，应用于食品工业。
