Mishra Amrita, Tripathy Suraj Kumar, Yun Soon-Il
Department of Food Science and Technology, College of Agriculture and Life Sciences, Chonbuk National University, Jeonju 561-756, South Korea.
J Nanosci Nanotechnol. 2011 Jan;11(1):243-8. doi: 10.1166/jnn.2011.3265.
In the present study we investigated the extra cellular synthesis of gold and silver nanoparticles by using the yeast Candida guilliermondii. The formation of noble metal nanoparticles was monitored by the UV-Visible spectroscopy. As prepared gold and silver nanoparticles showed distinct surface plasmon peaks at 530 nm and 425 nm respectively. Phase and morphology of the as synthesized materials were investigated by X-ray diffraction and electron microscopy techniques respectively. XRD patterns confirmed the formation of gold and silver nanoparticles with face centered cubic structures. Bio-TEM images showed the formation of near spherical, well dispersed gold and silver nanoparticles in the size range of 50-70 nm and 10-20 nm respectively. The biosynthesized nanoparticles were tested for their antimicrobial activity against five pathogenic bacterial strains. The highest efficiency for both gold and silver nanoparticles was observed against Staphylococcus aureus. A comparative study was also done to find the effect of chemically synthesized noble metal nanoparticles against the above test strains. Chemically synthesized particles had no antimicrobial activity against any of the pathogenic strains. The results obtained suggest that biosynthesized gold and silver nanoparticles can be used as effective antimicrobial agents against some of the potential harmful pathogenic microorganisms.
在本研究中，我们利用季也蒙毕赤酵母研究了金和银纳米颗粒的胞外合成。通过紫外可见光谱监测贵金属纳米颗粒的形成。所制备的金和银纳米颗粒分别在530 nm和425 nm处显示出明显的表面等离子体峰。分别通过X射线衍射和电子显微镜技术研究了合成材料的相和形态。XRD图谱证实形成了具有面心立方结构的金和银纳米颗粒。生物透射电镜图像显示分别形成了尺寸范围为50 - 70 nm和10 - 20 nm的近球形、分散良好的金和银纳米颗粒。测试了生物合成的纳米颗粒对五种致病细菌菌株的抗菌活性。观察到金和银纳米颗粒对金黄色葡萄球菌的效率最高。还进行了一项比较研究，以发现化学合成的贵金属纳米颗粒对上述测试菌株的影响。化学合成的颗粒对任何致病菌株均无抗菌活性。所得结果表明，生物合成的金和银纳米颗粒可作为针对某些潜在有害致病微生物的有效抗菌剂。
