Synthesis of bioderived silver nanoparticles from Tn antigen specific lectin from Butea monosperma seeds and its antimicrobial activity.

Silver nanoparticles, have a variety of biological properties including antimicrobial effects, due to their high surface-to-volume ratio. Lectins are carbohydrate binding proteins of non-immune origin. Since few legume lectins are known for their antibacterial activity at higher concentrations, in the present study we demonstrated the synthesis of bio derived Tn antigen specific lectin coated silver nanoparticles (AgNPs) to verify the increase in efficacy of lectin against pathogenic bacterial strains. A legume lectin from Butea monosperma was purified from seeds in a single step to six-fold, by affinity chromatography through galactose coupled seralore-4B column and purity was homogenized by SDS-PAGE. The preceding study was expanded by synthesizing BML coated AgNPs and characterisation using UV-Vis spectroscopy, XRD, FTIR, SEM-EDX, TEM-EDX and DLS analysis. UV-spectra revealed a broad absorption around 400 nm. XRD peaks confirmed the formation of AgNPs and crystalline nature respectively. FTIR analysis showed the presence of O-H/N-H, CO, C-O/C-N as functional groups and a peak at wavenumber 955 cm-1 indicates the presence Ag-O/Ag-N bond, revealing the interaction of BML was successful with silver. The SEM and TEM images display bioderived AgNPs were spherical, and rough with mean particle size of 153.9 nm as validated by DLS. Antimicrobial assay showed inhibiting activity against uropathogenic Escherichia coli (UPEC) and infectious Salmonella typhi. Our results highlight the bio-synthesis and enhanced inhibition of bacterial growth by lectin coated AgNPs. The study confirms the increase in efficiency of lectin coated AgNPs against infectious bacteria which makes it a potential candidate for the development of bio-based antimicrobial agents.