Biosynthesis of silver nanoparticles using pre-hydrolysis liquor of Eucalyptus wood and its effective antimicrobial activity

Herein, we described for the first time, biosynthesis of silver nanoparticles (AgNPs) using pre-hydrolyzed liquor of Eucalyptus wood under ambient conditions. The pre-hydrolyzed liquor containing a high amount of metabolites such as polyphenols, hemicelluloses and its derivatives are mainly assisted for the reduction and stabilization process of Ag+ ions to AgNPs. The formation of AgNPs is monitored by recording the UV-vis spectrophotometer for surface plasmon resonance (SPR) peak observed at 415 nm. The intensity of SPR increased linearly with increasing the reaction time at ambient condition. X-ray diffraction (XRD) pattern of AgNPs reveals the formation of face-centered cubic structure. Field emission electron microscopy (FESEM) and transmission electron microscopy (TEM) images show the spherical shaped particles and narrow size distribution with an average diameter of 25-30 nm. The elemental analysis by energy dispersive X-ray (EDAX) analysis confirms the presence of Ag as the major amount and is found to be 82%. Analysis of the fourier transform infrared (FT-IR) spectra of the NPs revealed the presence of phytoconstituents from pre-hydrolyzed liquor adsorbed on the surface of AgNPs. Moreover, in vitro, antimicrobial activity is found to be effective for as -synthesized AgNPs on tested bacteria (viz., P. aeruginosa, S. aureus and E. coli) followed by fungus (C. oxysporum, P. chrysogenum, C albicans and A.niger). Thus, these results suggest the use of biosynthesized AgNPs as effective growth inhibitors for various biomedical applications. (C) 2016 Elsevier Inc. All rights reserved.