ANTIBACTERIAL ACTIVITIES OF CRUDE EUDRILUS EUGENIAE EXTRACT - MEDIATED SILVER NANOPARTICLES ON ISOLATES FROM DIABETIC PATIENTS WITH FOOT INFECTIONS

Abstract

Diabetic foot infection pose a significant challenge to health care system because of its tremendous utilization of resources.The antibacterial activities of crude extract of Eudrilus eugeniae and extract-mediated silver nanoparticles were investigated against isolates from patients with diabetic foot infection using agar well diffusion method. Saponins, proteins, terpenoids, phenols and steroids were detected in the crude extract and fractions. Crude ethanol, ethyl-acetate and aqueous fractions at 4mg and 8mg showed very weak inhibitory zone in diameter (mm) on Psuedomonas aeruginosa, Staphylococcus aureus, Streptococcus pyogenes, Klebsiella pneumoniae and Escherichia coli. Dark brown aqueous extract-mediated silver nanoparticles (AAgNPs) was formed which gave maximum absorbance at 408nm. The synthesized particles were spherical, less aggregated and contained alkanes, esters and alcohol functional groups. The zones of inhibition produced by AAgNPs (at 1:4 dilution) were 15.33±0.58 mm and 17.67±0.58 mm against E. coli and P aeruginosa while at 1:5 dilution, 12.33±2.08 mm, 14.67±0.58 mm and 15.33±1.16 mm were zones of inhibition produced against E. coli, K. pneumoniae and P aeruginosa respectively. The minimum inhibitory concentration ( MIC) of AAgNPs against P. aeruginosa was at 1.25mg/ml while it was at 2.5mg/ml against E. coli and K. pneumoniae. The extract was bacteriostatic on the test isolates. Significant (P<0.05) wound closure was observed in rats from groups 1-6, which were topically treated with AAgNPs from Day 0 (1.00±0.44mm to 1.20±0.25 mm) to Day 14 (0.30±0.00 mm to 0.73±0.25 mm) compared to group 7 (1.21±0.10mm to 1.47±0.21mm). The administration of ointment of AAgNPs on the rats did not show skin irritation, rashes and other allergic reactions. The results of the finding showed the potential of AAgNPs as a safe topical therapeutic agent.