Biogenesis of Bacterial and Fungal Endophytic Mediated Silver Nanoparticles

Abstract

Aim: Nanoparticles play an important role to develop materials that are light, effective and ecofriendly with diverse applications. In this study, Bacterial and Fungal endophytes were screened for the synthesis of AgNPs.Materials and Methods: Endophytes for biogenesis of nanoparticles was isolated from various explants. Selected bacterial and fungal endophytes were identified by 18s rRNA and 16s rRNA sequencing. Endophyte mediated silver nanoparticles were characterized using different techniques like UV/Visible spectroscopy, XRD, HRTEM, DLS, EDX and FTIR.Results:Optimization of AgNP synthesis by endophytic bacterial isolate Bacillus cereus showed optimum 5 mM silver nitrate concentration, reaction mixture temperature 37-40°C, reaction time 30 min and PVP as stable surfactant. Characterization carried out using advanced analytical instrumentation showed sharp peak at 424 nm by UV/Visible spectroscopy. According to XRD and HR-TEM data analyzed it was observed that average size of AgNP was 12.4 and 12.9 nm respectively. DLS and zeta potential showed nanoparticles are dispersed evenly, FTIR analysis confirmed coating with primary and secondary amino acids which is responsible or stability of nanoparticles. EDX confirmed elemental composition of silver nanoparticles.Conclusion:Synthesized nanoparticles are uniform in size, ecofriendly, good bio compatibility, easy processing and stable. We can further study potential biological activity like plant growth promotion, nano pesticide encapsulations, antifungal, anti-bacterial, anti-oxidant and cytotoxicity of these synthesised AgNPs.

Keywords: DLS; FTIR; HRTEM; Silver nanoparticles; XRD