Anti-bacterial and anti-cancerous potential of medicinal plant mediated biofabricated nanoparticles: A question to its selective cytotoxicity?

Introduction: Physical, chemical and biological methods are the widely available approaches for nanoparticle synthesis. The common problems associated with nanoparticles assembly are control of crystal growth, stability, size,... [ view full abstract ]

Introduction: Physical, chemical and biological methods are the widely available approaches for nanoparticle synthesis. The common problems associated with nanoparticles assembly are control of crystal growth, stability, size, shape, and aggregation. Plants are the most exploited biological platform for safe, eco-friendly, precise morphology and large-scale production of nanoparticles. Nanoparticles fabricated using medicinal plant extract have advance potential in the area of nanomedicine. High surface to volume ratio of nanoparticle enhances the local active biomolecules concentration, leading to many folds increase in the medicinal potentials. Despite the remarkable development of nanotechnology, relatively little is known about the biomolecules characterized over nanoparticles in green synthesis and its fate inside the biological system.

Methods: Hence, we fabricated the silver nanoparticles (AgNPs) using different indigenous medicinal plants of India, Syzygium cumini (1:1.5), Azadirachta indica (1:3), Acorus calamus (1:10) and Pongamia pinnata (1:10). The biofabricated AgNPs were purified through size exclusion chromatography using sodiumhexametaphosphate buffer. Biofabrication of AgNPs was characterized using different spectroscopic and microscopic techniques. The significant effect of biofabricated AgNPs was studied on the viability of prokaryotic and eukaryotic cells.

Results: Henceforth, the cytotoxic propensity of spherical biofabricated AgNP formulations were screened against Gram-positive (Bacillus subtilis), Gram-negative (Escherichia coli), cancerous (fibrosarcoma, HT1080) and non-cancerous (human embryonic kidney, HEK293) cell lines. The nanoparticle formulations showed relatively higher cytotoxic propensity against cancerous cell lines than non cancerous one.

Discussion: The surface roughness and reactive oxygen species (ROS) measurements indicated that AgNP formulations modulate the cell viability predominantly by ROS-mediated change in cytoskeleton assembly and/or disruptive change in membrane morphology upon direct interaction with membrane. The internalization assay of biofabricated AgNPs shows the nuclear associated co-localization leads to its genotoxicity. Furthermore, the nanoparticle formulations obtained upon purification showed higher monodispersivity and enhanced selective cytotoxic propensity towards Gram-positive bacteria and cancerous cell lines. Hence, the overall study emphasizes the biofabrication of AgNP using medicinal plants with multifaceted biomedical application may find its significant role in nanomedicine.