ANTIBACTERIAL EFFICACY OF SOME STANDARD ANTIBIOTICS DISCS COATED WITH BIOLOGICALLY SYNTHESIZED SILVER NANOPARTICLES FROM Cassia occidentalis LEAVES

Biologically produced silver nanoparticles are being used extensively in the area of medicine. Extracellular biosynthesis of silver nanoparticles was carried out by using Cassia occidentalis leaves extracts for the reduction of aqueous silver ions in short phase. This research is aimed at determining the antibacterial efficacy of some standard antibiotics discs coated with biologically synthesized silver nanoparticles from Cassia occidentalis leaves. Preliminary phytochemical analysis of aqueous extracts revealed the presence tannins, flavonoids, saponins, glycosides and triterpenoids. The silver nanoparticles formation was confirmed by the colour change of plant extracts from yellow to dark brown. Standard antibiotics discs were coated with Phytosynthesized silver nanoparticles at various concentrations and tested for antibacterial activity using disc diffusion method. The test cultures include S. typhi, P. aeruginosa, K. pneumoniae and E. coli. The antibacterial activity of standard antibiotics discs coated with Phytosynthesized silver nanoparticles was analyzed by measuring the zone of inhibition. The result indicated that S. typhi, K. pneumoniae, P. aeruginosa and E. coli are sensitive; similarly the MIC result shows that S. typhi and E. coli are sensitive at 250µg/ml concentration whereas K. pneumoniae and P.aeruginosa are sensitive at 500 µg/ml; the MBC result indicated that E. coli, S. typhi and K. pneumoniae are sensitive at 250 µg/ml, 500 µg/ml, 1000 µg/ml respectively while P. aeruginosa was resistant. Antibiotics discs coated with phytosynthesized AgNPs showed higher antibacterial effects against the bacterial isolates when compared with standard antibiotics alone.