ABSTRACT

In this study, the biosynthesis of extracellular silver nanoparticles (AgNPs) was obtained using Pseudomonas aeruginosasupernatant integrated with gamma radiation. The biosynthesis was confirmed by UV-Vis Spectrophotometer. The Atomic Force Microscopy (AFM) recorded the spherical nanoparticle sizes of 10 nm, while the Dynamic Light Scattering (DLS) recorded the size range of 6.7 to 12.1 nm (84.2%) and the particles were monodispersed. The Gas Chromatography/Mass Spectroscopic analysis of the bacterial filtrate suggested the presence of ethylene glycol derivatives, which may act as a reducing agent. In addition, the impact of synthesized AgNPs on the cell growth and metabolite contents of Chlorella vulgaris and Dictyochloropsis splendida was evaluated. The low AgNPs concentrations (1, 3, and 5 mg L^-1) enhanced the lipid production but at the expense of cell growth. All AgNPs concentrations however displayed negative effects on the carbohydrates content. The fatty acid profile of the microalgal species studied was significantly affected by the addition of AgNPs. The saturated fatty acids represented the highest composition (61–67%) of the total fatty acids, and palmitic acids (16:0) were dominant (43.06–46.57%). Lipids of this composition could withstand autoxidation during storage and are perfect feedstock for biodiesel and other lipid-based applications.Not StartedCompletedRejected

抽象的

在这项研究中，使用铜绿假单胞菌上清液与γ射线结合获得了细胞外银纳米颗粒（AgNPs）的生物合成。通过UV-Vis分光光度计确认生物合成。原子力显微镜（AFM）记录的球形纳米颗粒尺寸为10 nm，而动态光散射（DLS）的记录尺寸范围为6.7至12.1 nm（84.2％），颗粒被单分散。细菌滤液的气相色谱/质谱分析表明存在乙二醇衍生物，乙二醇衍生物可作为还原剂。此外，评估了合成的AgNPs对小球藻和小球藻的细胞生长和代谢产物含量的影响。低AgNPs浓度（1、3和5 mg L ^-1）增加了脂质的产生，但以细胞生长为代价。然而，所有AgNPs浓度均对碳水化合物含量显示负面影响。AgNP的添加显着影响了所研究的微藻物种的脂肪酸谱。饱和脂肪酸占总脂肪酸的最高组成（61–67％），而棕榈酸（16：0）占主导地位（43.06–46.57％）。这种成分的脂质在储存过程中可以承受自氧化作用，是生物柴油和其他基于脂质的应用的理想原料。