Bioactive Nanoparticles from Cassia fistula L. Seed Aqueous Extract: Assessment of Multiple Biological Activities

Cassia fistula L., a flowering plant of the leguminous family (Fabaceae), has been explored for its potential in synthesizing silver nanoparticles. This plant is known for its medicinal properties, making it a promising candidate for applications in nanobiotechnology.

The researchers employed a combination of hot and cold extraction procedures to synthesize silver nanoparticles using seed extracts of C. fistula . The identity and characteristics of these nanoparticles were verified through various techniques, including chromatography, imaging microscopy, X-ray diffraction and scanning electron microscopy. Biological activities such as antioxidant and antibacterial properties were tested. For antioxidant activity, a reaction mixture consisting of 50 μl of seed extract and 5 ml of a 0.04% (w/v) DPPH solution was used. Antibacterial activity was evaluated against Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus and Streptococcus pyogenes at concentrations of 0.125, 0.25, 0.5 and 1 mg/ml of AgNPs. Additionally, the antibiofilm effect and hemolysis impact were studied.

The synthesized silver nanoparticles demonstrated significant biological activities, including antioxidant and antibacterial effects. The diameters of the zones of inhibition for P. aeruginosa at a concentration of 1 mg/ml were 20 mm for cold extract and 18 mm for E. coli using hot extract. These findings highlight the potential of C. fistula as a sustainable source for environmentally friendly nanomaterials, contributing to advancements in medical and environmental sciences. Finally, the use of silver nanoparticles from Cassia fistula encourages sustainable and productive agricultural practices, by improving plant health and yield, potentially revolutionizing agricultural methods.