Department of Biotechnology, University of Malakand, Khyber Pakhtunkhwa, Pakistan.
Department of Food Science and Technology, College of Agriculture and Life Sciences, Jeonbuk National University, Jeonju, Republic of South Korea.
PLoS One. 2023 Oct 26;18(10):e0287080. doi: 10.1371/journal.pone.0287080. eCollection 2023.
Multi-drug resistant bacteria sometimes known as "superbugs" developed through overuse and misuse of antibiotics are determined to be sensitive to small concentrations of silver nanoparticles. Various methods and sources are under investigation for the safe and efficient synthesis of silver nanoparticles having effective antibacterial activity even at low concentrations. We used a medicinal plant named Salvia moorcroftiana to extract phytochemicals with antibacterial, antioxidant, and reducing properties. Three types of solvents; from polar to nonpolar, i.e., water, dimethyl sulfoxide (DMSO), and hexane, were used to extract the plant as a whole and as well as in fractions. The biosynthesized silver nanoparticles in all extracts (except hexane-based extract) were spherical, smaller than 20 nm, polydispersed (PDI ranging between 0.2 and 0.5), and stable with repulsive force of action (average zeta value = -18.55±1.17). The tested bacterial strains i.e., Klebsiella pneumoniae, Pseudomonas aeruginosa, Staphylococcus aureus, and Enterococcus faecalis were found to be sensitive to even small concentrations of Ag-NPs, especially P. aeruginosa. The antibacterial effect of these Ag-NPs was associated with their ability to generate reactive oxygen species. DMSO (in fraction) could efficiently extract antibacterial phytochemicals and showed activity against MDR bacteria (inhibition zone = 11-12 mm). Thus, the antibacterial activity of fractionated DMSO extract was comparable to that of Ag-NPs because it contained phytochemicals having solid antibacterial potential. Furthermore, Ag-NPs synthesized from this extract owned superior antibacterial activity. However, whole aqueous extract-based Ag-NPs MIC was least (7-32 μg/mL) as compared to others.
多药耐药细菌有时被称为“超级细菌”,它们是由于抗生素的过度和滥用而产生的,被确定对小浓度的银纳米粒子敏感。正在研究各种方法和来源,以安全有效地合成具有有效抗菌活性的银纳米粒子,即使在低浓度下也是如此。我们使用一种名为鼠尾草的药用植物来提取具有抗菌、抗氧化和还原特性的植物化学物质。使用三种溶剂;从极性到非极性,即水、二甲基亚砜(DMSO)和己烷,提取整株植物以及各部分。在所有提取物(基于己烷的提取物除外)中合成的银纳米粒子都是球形的,小于 20nm,多分散性(PDI 在 0.2 和 0.5 之间),并且具有斥力(平均 zeta 值=-18.55±1.17)。测试的细菌菌株,即肺炎克雷伯菌、铜绿假单胞菌、金黄色葡萄球菌和粪肠球菌,即使对小浓度的 Ag-NPs 也很敏感,特别是铜绿假单胞菌。这些 Ag-NPs 的抗菌作用与其生成活性氧的能力有关。DMSO(在馏分中)能够有效地提取具有抗菌作用的植物化学物质,并对 MDR 细菌表现出活性(抑菌圈=11-12mm)。因此,馏分 DMSO 提取物的抗菌活性与 Ag-NPs 相当,因为它含有具有坚实抗菌潜力的植物化学物质。此外,从该提取物合成的 Ag-NPs 具有优越的抗菌活性。然而,基于全水提取物的 Ag-NPs MIC 最低(7-32μg/mL)。