Guar gum cinnamate ouzo nanoparticles for bacterial contact killing in water environment

Herein we report the synthesis of newer guar gum cinnamate esters (GGC) following a Hofmeister cation guided homogeneous phase reaction. High degree of substitution (DS) guar gum cinnamate was obtained using, cinnamic acid halide reactant at a 1:3 M ratio. The biopolymer was fully characterized in FT-IR,¹³C NMR, XRD and thermal analysis. Nanoparticles were further developed in a facile ouzo solvent diffusion technique. SEM studies confirmed quasi spherical shape of the nanoparticles (GGCN) with an average size of 200 nm. Nanoparticles GGCN, expressed antibacterial activity against water borne gram negative and gram positive bacteria. The MIC was recorded at 300 μg mL^-1against Escherichia coli and 500 μg mL^-1against Staphylococcus aureus. Bacterial contact killing was confirmed from the bacterial morphology studies in SEM. Thus, nanoparticles from GGC may be employed for bacterial killing and water decontamination.