Basilla alba (Indian Spinach) fruit derived green fluorescent pigment mediated rapid, one step synthesis and biological potential of silver nanoparticles

Introduction: Due to the adverse effects of chemically synthesized nanoparticles on both the environment and biological systems, there is a pressing need to discover a safe and environmentally friendly approach. The present study presents a rapid, one-step and, environmentally friendly method for producing silver nanoparticles (AgNPs) using a green fluorescent pigment (GP) extracted from Indian spinach fruits (Basella alba).

Methods: The GP exhibited pink fluorescence, and its fluorescence mechanism was investigated using spectrofluorophotometry and computational design. The GP-mediated synthesis of AgNPs (GP-AgNPs) was rapid, occurring within just 30 minutes under sunlight. The characteristics of GP-AgNPs, including size and topography, were precisely defined using various sophisticated analytical techniques. The antimicrobial, antioxidant, and SPF enhancing potential of GP and GP-AgNPs) was explored.

Results: The average size of the AgNPs was 102 nm, zeta potential of -12.1 mV, and a polydispersity index of 0.251, indicating stability and dispersion. The biocidal efficacy of GP-AgNPs was assessed against bacterial pathogens: Pseudomonas aeruginosa, Escherichia coli, Staphylococcus aureus, and Bacillus sp. Additionally, the potential of GP-AgNPs to enhance the sun protection factor (SPF) of commercial sunscreens was explored including additive effects. The antioxidant potential of GP-AgNPs and GP was133.87% and 140.01%, respectively, in comparison with 37.61% for L-Ascorbic acid.

Conclusion: This study highlights the fluorescent green pigment derived from a common leafy vegetable for the environmentally friendly, and rapid synthesis of silver nanoparticles without additional energy, and toxic chemical reducing agents. Furthermore, their promising biological applications were studied.