Synthesis and characterization of silver nanoparticles developed using a novel lipopeptide(s) biosurfactant and evaluating its antimicrobial and cytotoxic efficacy.

Abstract

Novel bacterial lipopeptide(s) (LPs) biosurfactant obtained from Pseudomonas sp. OXDC12 were used to synthesizeLPs silver nanoparticles (LPs-Ag-NPs). LPs provided excellent colloidal stability by acting as a stabilizing/capping agent. The LPs-Ag-NPswere characterized using Field-Emission Scanning Electron Microscopy, Ultraviolet-visible spectroscopy,Fourier-transform infrared, Atomic force microscopy andX-Ray Diffraction. The formulation exhibited the production of monodisperse NPs with spherical morphology withan average diameter of 42.43 ± 5.2 nm.The metallic NP (LPs-Ag-NPs) formulation displayed remarkable antimicrobial/antifungal activity against Candida albicans (22.0 ± 1.3 mm), Fusarium oxysporum (28.0 ± 1.4 mm),Mucor sp. (26.0 ± 1.6 mm),Staphylococcus aureus MTCC96 (05.0 ± 0.6 mm), Salmonella typhimurium NCTC 74 (11.0 ± 0.2 mm), Klebsiellapneumnoniae (14.0 ± 0.3 mm) and Escherichiacoli MTCC1687 (12.6 ± 0.7 mm). The minimum inhibitory concentration (MIC) value was very less for LPs-Ag-NPs formulation when compared to purified LPs biosurfactant. LPs-Ag-NPs formulations showed cytotoxic activity against cancerous cells (L20B and RD; 80–94% at 80 µg/ mL) and were significantly less toxic against normal cells (PMC) showing only 22% cell reduction at 80 µg/ mL.In all, itwas concluded that capping the LPs on Ag-NPs successfully enhanced its antimicrobial and anti-cytotoxic properties.