Antimicrobial effect of biosynthesis of selenium nanoparticles by Pseudomonas aeruginosa on bacteria isolated from wounds and burns

Abstract

Abstract: background: In recent decades, the rise of antibiotic resistance as critical global health challenges, necessitating innovative approaches to address these pressing issues. The Center of Disease Control (CDC) estimates that antibiotic resistance is responsible for  nearly 5 million deaths in 2019  Objective: This study aims to biosynthesise selenium nanoparticles and the possibility of using as antimicrobal. Methods:  Samples were collected from Al-Diwaniyah Teaching Hospital in Al-Diwaniyah Governorate - Iraq , period from April 1, 2023 to June 1, 2023. Bacterial samples were collected from wounds and burns, then they were diagnosed using (Vitek-2 compact system- Biomerieux-France), then all the collected bacterial species were tested to produce selenium nanoparticles and the best bacteria capable of producing them were selected.  The synthesis process involved incubation, centrifugation, and purification. The antimicrobal activity of SeNPs was evaluated .Results :   Pseudomonas aeruginosa was the predominant pathogen accounting for 30%, followed by Bacillus (24%), Staphylococcus (16%), Escherichia coli (8%), and Candida albicans (12%). Mixed infections are found in 10%. Statistical analysis showed (chi-square = 40.32, p < 0.0001). The bacilli showed high sensitivity to ciprofloxacin (Cip) with a mean diameter of 28 ± 1.02, while amoxicillin (AX), ceftoxime (CTX), doxycycline (DO), and carbenicillin (PY) had no inhibitory effect (0 ± 0). Staphylococci showed sensitivity to ciprofloxacin (18 ± 0.64), amoxicillin (13 ± 0.22), cefatoxime (12 ± 0.4), doxycycline (12 ± 0.4), nitrofuranthone (THAT) (11 ± 1), and neomycin (17.2 ± 1.1). Escherichia coli showed sensitivity to ciprofloxacin (28 ± 1.02) and doxycycline (19 ± 1.4), while Candida albicans showed resistance to all antibiotics tested. Antimicrobial activity was measured using concentrations of 125, 250, 500, and 1000 μg/mL. Results show a concentration-dependent increase in inhibitory effects. Antibiofilm activity ranges from 2 to 1048 μg/mL.Discussion:  Lower concentrations (125 µg/ml), minimal inhibition was observed, but as the concentration increased, a clear trend of enhanced inhibition emerged. Notably, at 250 µg/ml, significant growth inhibition was evident, with a concentration-dependent response. The highest concentration (1000 µg/ml) exhibited the most substantial inhibitory effects. The absence of inhibition in the negative control confirms the specificity of nano selenium's impact.conclusion. : The results demonstrate concentration-dependent inhibitory effects of nano selenium on various bacterial species.