Bacillus subtilis was used for biogenic of silver nanoparticles. Characterization of the prepared silver nanoparticles was done by UV–Vis spectroscopy, Transmission Electron Microscopy (TEM), and Fourier Transform Infrared Spectroscopy (FT-IR). The particle size of the prepared nanoparticles ranges from 3 to 20 nm with spherical or roughly spherical forms. The antimicrobial efficacy of the produced nanoparticles was investigated against five strains of multidrug resistant microorganisms including: Staphylococcus aureus (MRSA), Staphylococcus epidermidis, Klebsiella. pneumoniae, Escherichia coli and Candida albicans tested as yeast. During this study, the minimum inhibitory concentrations (MICs) and the minimum lethal concentrations (MLCs) of synthesized silver nanoparticles were detected using selected strains of the genus Bacillus by a broth dilution method. The rate of MIC of the prepared silver nano-particles versus the investigated clinical isolates exhibit a massive anti-microbial efficacy; (230 µgml⁻¹) for MRSA; 180 for Staphylococcus epidermidis, 200 for Escherichia coli and 100 µgml⁻¹ for Candida albicans. On the other hand, the lowest anti-microbial efficacy (300 µgml⁻¹) was appeared for Klebsiella pneumonia. The obtained results demonstrated the effectiveness of the biogenic nanoparticles and the possibility of using them as a new method in combating infectious diseases.

枯草芽孢杆菌用于银纳米颗粒的生物源。通过紫外-可见光谱、透射电子显微镜（TEM）和傅里叶变换红外光谱（FT-IR）对制备的银纳米颗粒进行表征。制备的纳米粒子粒径范围为3～20 nm，呈球形或近似球形。研究了所生产的纳米颗粒针对五种多重耐药微生物菌株的抗菌功效，包括：金黄色葡萄球菌(MRSA)、表皮葡萄球菌、克雷伯氏菌。肺炎链球菌、大肠杆菌和白色念珠菌被测试为酵母。在这项研究中，通过肉汤稀释法使用选定的芽孢杆菌属菌株检测了合成银纳米颗粒的最低抑菌浓度（MIC）和最低致死浓度（MLC）。所制备的银纳米颗粒与所研究的临床分离株的 MIC 比率表现出巨大的抗菌功效； (230 µgml ^-1 ) 对于 MRSA；表皮葡萄球菌为180，大肠杆菌为200，白色念珠菌为100 µgml ^-1 。另一方面，肺炎克雷伯菌的抗菌功效最低（300μgml ^-1 ）。获得的结果证明了生物纳米粒子的有效性以及将其用作对抗传染病的新方法的可能性。