Green synthesis of nanoparticles by probiotics and their application

Nanoparticles (NPs), which have unique properties due to their extremely small size and high surface area to volume ratio, have attracted considerable attention and become an important tool for innovation in various fields. Traditionally, NPs are synthesized by physical and chemical processes, but these methods have high capital costs and energy demand, and involve the use of toxic and hazardous chemicals, which are prone to secondary pollution of the environment. In recent years, the use of microorganism-mediated methods has emerged as an alternative to traditional physical and chemical methods. The synthesis of NPs by microorganism has the advantages of non-toxicity, eco-friendliness, low-cost, reproducibility in production, easy amplification, and well-defined morphology. Probiotics are a kind of active microorganisms beneficial to the host. Compared with other microorganisms, probiotics are characterized by non-pathogenicity, rapid growth and regulation of gene expression, and produce a variety of proteins and enzymes involved in the synthesis of NPs. Therefore, the production of NPs using probiotics is an environmentally friendly and commercially attractive method, which provides new ideas and approaches for the application of NPs in the fields of biomedicine, agriculture and environmental remediation. This review aims to summarize the literature on the biosynthesis of NPs by probiotics and their synthetic mechanisms and applications.