Abstract

The antibacterial activity of synthetically prepared gold nanoparticles is well-known. In this unique study, the Suvarna bhasma containing the incinerated gold particles was tested for its bactericidal activity against Pseudomonas aeruginosa. The microanalysis of Suvarna bhasma was done through scanning electron microscopy, which revealed that, the gold particles' size ranged from 28 nm to 8.1 µm, forming particle agglomerates of a spherical shape with rough surfaces and heterogeneous distribution. The transition electron microscopy revealed that the particle size ranged between 2.2 to 18.96nm after the sonication of Suvarna bhasma. The energy dispersed X-ray analysis of the Suvarna bhasma sample revealed that it contained 86.3% gold, 3.1% oxygen, and 10.5% carbon. The X-ray diffraction findings of Suvarna bhasma showed four intense peaks of pure gold nanoparticles at (1 1 1), (2 0 0), (2 2 0), and (3 1 1) depicting that gold existed in a face-centered cubic crystalline lattice phase with an average particle size of 27.58 nm.
The Minimum Inhibitory Concentration of Suvarna bhasma, through the broth microdilution method, was seen to be 312µg / mL against Pseudomonas aeruginosa ATCC 27853 grown in brain-heart infusion. In contrast, the Minimum Bactericidal Concentration was 1250 µg / mL. This result was substantiated by scanning electron microscopy analysis of the P. aeruginosa (10 x 6 colony forming units) treated with 1000 µg/mL of Suvarna bhasma, showing cellular structural damage as membrane rupture, cell shrinking and death. Hence, Suvarna bhasma may be one of the futuristic antipseudomonal agents.

Key words: Suvarna bhasma, Microanalysis, incinerated gold nanoparticles, bactericidal, bacteriostatic