Essghaier Badiaa, Hannachi Hédia, Nouir Rihem, Mottola Filomena, Rocco Lucia
Laboratory of Biochemistry and Biotechnology LR01ES05, Department of Biology, Faculty of Sciences of Tunis, University Tunis El-Manar, Tunis 2092, Tunisia.
Laboratory of Vegetable Productivity and Environmental Constraint LR18ES04, Department of Biology, Faculty of Sciences, University Tunis El-Manar II, Tunis 2092, Tunisia.
Nanomaterials (Basel). 2023 Jun 28;13(13):1964. doi: 10.3390/nano13131964.
Novel silver nanoparticles were synthesized based on a simple and non-toxic method by applying the green synthesis technique, using, for the first time, the aqueous extract of an extremophile plant belonging to the subsp. species. AgNP characterization was performed via UV-Visible, front-face fluorescence spectroscopy, and FTIR and XRD analyses. AgNP formation was immediately confirmed by a color change from yellow to brown and by a surface plasmon resonance peak using UV-Vis spectroscopy at 420 nm. The biosynthesized AgNPs were spherical in shape with a size ranging from approximatively 14.13 to 21.26 nm. The presented silver nanoparticles exhibited strong antioxidant activity following a DPPH assay compared to ascorbic acid, with IC50 values of about 0.089 µg/mL and 22.54 µg/mL, respectively. The AgNPs showed higher antidiabetic capacities than acarbose, by inhibiting both alpha amylase and alpha glucosidase. The silver nanoparticles could affect various bacterial mechanisms of virulence, such as EPS production, biofilm formation and DNA damage. The silver nanoparticles showed no lysozyme activity on the cell walls of Gram-positive bacteria. The AgNPs also had a strong inhibitory effect on the virulence factor (extracellular enzymes, biofilm formation). The microscopic observation showed abnormal morphogenesis and agglomeration of exposed to AgNPs. The AgNPs showed no cytotoxic effect on human cells in an MTT assay. The use of novel silver nanoparticles is encouraged in the formulation of natural antimicrobial and antidiabetic agents.
基于一种简单且无毒的方法，采用绿色合成技术首次利用属于亚种物种的嗜极植物的水提取物合成了新型银纳米颗粒。通过紫外可见光谱、正面荧光光谱以及傅里叶变换红外光谱（FTIR）和X射线衍射（XRD）分析对银纳米颗粒进行了表征。通过颜色从黄色变为棕色以及在420 nm处使用紫外可见光谱观察到表面等离子体共振峰，立即确认了银纳米颗粒的形成。生物合成的银纳米颗粒呈球形，尺寸范围约为14.13至21.26 nm。与抗坏血酸相比，通过二苯基苦味酰基自由基（DPPH）测定法，所呈现的银纳米颗粒表现出较强的抗氧化活性，其半数抑制浓度（IC50）值分别约为0.089 µg/mL和22.54 µg/mL。银纳米颗粒通过抑制α淀粉酶和α葡萄糖苷酶，显示出比阿卡波糖更高的抗糖尿病能力。银纳米颗粒可影响多种细菌毒力机制，如胞外多糖（EPS）产生、生物膜形成和DNA损伤。银纳米颗粒对革兰氏阳性细菌细胞壁没有溶菌酶活性。银纳米颗粒对毒力因子（细胞外酶、生物膜形成）也有很强的抑制作用。显微镜观察显示，暴露于银纳米颗粒的细胞出现异常形态发生和聚集。在MTT测定中，银纳米颗粒对人细胞没有细胞毒性作用。鼓励在天然抗菌和抗糖尿病药物制剂中使用新型银纳米颗粒。
