Antibacterial Effects of Green Synthesized Silver Nanoparticles Using Anise (Pimpinella anisum L.) Against Pseudomonas aeruginosa

Abstract

Background: Pseudomonas aeruginosa is a ubiquitous and opportunistic pathogen that has garnered significant attention in the medical community due to its remarkable ability to develop resistance to a wide range of antibiotics.

Aim: This study was conducted to identify the antibacterial activity of both the synthesized AgNPs-Anise (Pimpinella anisum L.) and the traditional antibiotics against P. aeruginosa.

Materials and methods: After Anise (P. anisum L.) extraction, AgNPs was prepared, validated through the UV spectrophotometer, transmission electron microscopy (TEM) and Fourier transform infrared spectroscopy (FTIR); and then, used to prepare the AgNPs-Anise solution. Finally, P. aeruginosa isolates were re-cultured on Muller-Hinton agar (MHA) plates to examine the antibacterial activity of the four different concentrations of the AgNPs-Anise (50, 100, 200 and 400 μg/ml) solution as well as five traditional antibiotics including Gentamicin (GEN), Ceftazidime (CAZ), Amikacin (AK), Levofloxacin (LE), and Ciprofloxacin (CIP).

Results: Based on values of inhibition zone (mm), significant elevation (p≤0.0001) in antibacterial activity of different concentrations of AgNPs-Anis solution was seen at 50 μg/ml (20.83 ± 1.08 mm) while reduction was observed at 200 μg/ml (17.17 ± 0.79) when compared to other concentrations; 100 μg/ml (18.17 ± 0.79) and 400 μg/ml (19.83 ± 1.11). In comparison with traditional antibiotics, values of antibacterial activity of all AgNPs-Anis concentrations were significantly lowered than detected by AK (22.21 ± 1.1 mm), CAZ (18.14 ± 2.14 mm), CIP (29.3 ± 1.73 mm), GEN (22.5 ± 0.78 mm), and LEV (24.78 ± 2.08 mm). Among the selected antibiotics, antibacterial activity were increased significantly in CIP and decreased in CAZ comparing to others AK, GEN, and LEV.

Conclusion: The findings of the current study revealed that AgNPs-Anise was significantly having less antibacterial effects than conventional antibiotics. However, it's important to double-check specific applications and formulations, as the effectiveness can vary based on the type of nanoparticles and antibiotics used. Also, the use of NPs with antibiotics enhances the antibacterial effects while reducing the required dosage of antibiotics. This combination improves treatment efficacy and can help combat antibiotic resistance, as nanoparticles can deliver antibiotics more effectively to target pathogens.