In this study, biosynthesis of silver nanoparticles (AgNPs) by using Eurotium cristatum, isolated from Fuzhuan brick-tea and its antibacterial activity has been demonstrated. AgNPs were characterized at 425 nm as maximum absorbance peak by ultraviolet-visible spectrophotometry. The images of transmission electron microscopy revealed that AgNPs are spherical shape with at 15–20 nm in size. The X-ray diffraction pattern corresponding to planes (111), (200), (220), (311), and (222) demonstrated the crystalline nature of AgNPs. Fourier transform infrared spectrum showed that functional groups involved in reduction of silver ions to metal nanoparticles. For antibacterial application, AgNPs showed antibacterial activity against Pseudomonas aeruginosa, Escherichia coli, Staphylococcus aureus, Candida albicans, and Bacillus subtilis. It also acted synergistically with various antibiotics to inhibit growth of pathogenic strains, which produced an effect greater than the sum of their individual effects. For neomycin with no resistance to C. albicans, it combined with AgNPs, which had significant synergistic effect against C. albicans, with maximum inhibitory zone at 20.9 mm, which was 2.5-fold greater than that of AgNPs alone (8.2 mm). Other antibiotics combined with AgNPs also existed similar synergistic effect. Therefore, AgNPs-synthesized by E. cristatum could enhance antibacterial activity in combination with antibiotics against pathogenic strains through synergistic effects. It might provide a new strategy for treatment of resistant bacteria.

在这项研究中，通过使用生物合成的银纳米颗粒（的AgNPs）的散囊菌草，从茯砖茶及其抗菌活性已经证实分离。通过紫外可见分光光度法将AgNPs在425 nm处表征为最大吸收峰。透射电子显微镜的图像显示，AgNPs为球形，大小为15–20 nm。对应于平面（111），（200），（220），（311）和（222）的X射线衍射图证明了AgNP的晶体性质。傅立叶变换红外光谱表明，官能团参与将银离子还原为金属纳米颗粒。对于抗菌应用，AgNPs对铜绿假单胞菌，大肠杆菌，金黄色葡萄球菌，白色念珠菌和枯草芽孢杆菌。它也与多种抗生素协同作用以抑制病原菌株的生长，其产生的作用大于其各自作用的总和。对于对白色念珠菌无抗性的新霉素，它与AgNPs结合使用，对白色念珠菌具有明显的协同作用，最大抑制区在20.9 mm，比单独的AgNPs（8.2 mm）大2.5倍。其他与AgNPs结合的抗生素也存在相似的协同作用。因此，由E. cristatum合成的AgNPs通过协同作用，可与抗生素联合使用增强对病原菌株的抗菌活性。它可能为抗药性细菌的治疗提供新的策略。