Kitching Michael, Ramani Meghana, Marsili Enrico
School of Biotechnology, Dublin City University, Dublin, Dublin 9, Ireland.
Center for Materials science and Nano Devices, Department of Physics, SRM University, Kattankulathur, India.
Microb Biotechnol. 2015 Nov;8(6):904-17. doi: 10.1111/1751-7915.12151. Epub 2014 Aug 26.
Gold nanoparticles (AuNPs) are a widespread research tool because of their oxidation resistance, biocompatibility and stability. Chemical methods for AuNP synthesis often produce toxic residues that raise environmental concern. On the other hand, the biological synthesis of AuNPs in viable microorganisms and their cell-free extracts is an environmentally friendly and low-cost process. In general, fungi tolerate higher metal concentrations than bacteria and secrete abundant extracellular redox proteins to reduce soluble metal ions to their insoluble form and eventually to nanocrystals. Fungi harbour untapped biological diversity and may provide novel metal reductases for metal detoxification and bioreduction. A thorough understanding of the biosynthetic mechanism of AuNPs in fungi is needed to reduce the time of biosynthesis and to scale up the AuNP production process. In this review, we describe the known mechanisms for AuNP biosynthesis in viable fungi and fungal protein extracts and discuss the most suitable bioreactors for industrial AuNP biosynthesis.
金纳米颗粒（AuNPs）因其抗氧化性、生物相容性和稳定性而成为一种广泛应用的研究工具。金纳米颗粒的化学合成方法常常会产生有毒残留物，引发环境问题。另一方面，利用活的微生物及其无细胞提取物进行金纳米颗粒的生物合成是一种环境友好且低成本的过程。一般来说，真菌比细菌能耐受更高的金属浓度，并且能分泌大量细胞外氧化还原蛋白，将可溶性金属离子还原为不溶性形式，最终形成纳米晶体。真菌拥有尚未开发的生物多样性，可能会提供用于金属解毒和生物还原的新型金属还原酶。为了缩短生物合成时间并扩大金纳米颗粒的生产规模，需要深入了解真菌中金纳米颗粒的生物合成机制。在这篇综述中，我们描述了活真菌和真菌蛋白提取物中金纳米颗粒生物合成的已知机制，并讨论了最适合用于工业金纳米颗粒生物合成的生物反应器。
