Microbial biosynthesis of metal nanoparticles has been extensively studied for the applications in biomedical sciences and engineering. However, the mechanism for their synthesis through microorganism is not completely understood. In this study, several culture media were investigated for their roles in the microbial biosynthesis of silver nanoparticles (AgNPs). The size and morphology of the synthesized AgNPs were analyzed by UV–vis spectroscopy, Fourier-transform-infrared (FT-IR), transmission electron microscopy (TEM), and dynamic light scattering (DLS). The results demonstrated that nutrient broth (NB) and Mueller-Hinton broth (MHB) among tested media effectively reduced silver ions to form AgNPs with different particle size and shape. Although the involved microorganism enhanced the reduction of silver ions, the size and shape of the particles were shown to mainly depend on the culture media. Our findings suggest that the growth media of bacterial culture play an important role in the synthesis of metallic nanoparticles with regard to their size and shape. We believe our findings would provide useful information for further exploration of microbial biosynthesis of AgNPs and their biomedical applications.

中文翻译：

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不同培养基中银纳米颗粒的微生物生物合成

金属纳米颗粒的微生物生物合成已被广泛研究用于生物医学和工程中。但是，通过微生物合成它们的机理尚不完全清楚。在这项研究中，研究了几种培养基在银纳米颗粒（AgNPs）的微生物生物合成中的作用。合成的AgNPs的大小和形态通过紫外可见光谱，傅立叶变换红外（FT-IR），透射电子显微镜（TEM）和动态光散射（DLS）进行了分析。结果表明，被测培养基中的营养肉汤（NB）和Mueller-Hinton肉汤（MHB）可有效还原银离子，形成具有不同粒径和形状的AgNP。尽管所涉及的微生物增强了银离子的还原，颗粒的大小和形状显示主要取决于培养基。我们的发现表明，细菌培养的生长培养基就其大小和形状而言，在金属纳米颗粒的合成中起着重要作用。我们相信我们的发现将为进一步探索AgNPs的微生物生物合成及其生物医学应用提供有用的信息。