Silver nanoparticles encapsulation, characterisation, antimicrobial and antioxidant effects of Fritillaria Imperialis extracts of Sason origin

The increasing drug resistance in recent years has revived interest in the discovery of traditional medicines from natural sources. Plants of the Fritillaria genus are attracting attention every day with their rich bioactive components. These plants contain various compounds with anti-inflammatory, antitussive, neuroprotective, and antitumor activities. Designed nanoparticles (NPs) have emerged as a potential alternative in infection treatment due to their antibacterial effects. The antimicrobial activity of silver nanoparticles is based on their ability to bind to bacterial surfaces and induce oxidative stress. However, there are insufficient studies on the activities of AgNP-synthesized forms of the Fritillaria imperialis L. plant. In this study, the characterization of AgNPs synthesized with the bulb, stem, and flower extracts of the F. imperialis plant originating from Batman/Sason and the investigation of their antimicrobial effects and antioxidant capacities were aimed. The flower (water and ethanol extract), stem, and bulb were homogenized into four groups. The extracts were then divided into two parts, with half left in their pure form and half encapsulated with AgNP. Thus, the study consisted of a total of eight groups. After optimization, XRD, FTIR, and SEM analyses were performed for characterization. Then, antimicrobial activity tests were conducted on Candida utilis, Neisseria meningitidis, Listeria monocytogenes, Klebsiella pneumoniae, Acinetobacter baumannii, Salmonella paratyphi, Aspergillus niger, MRSA and Escherichia coli bacteria. Additionally, the synergistic application of antibiotics and extracts was compared with the combined application of penicillin antibiotic disks and extracts. Furthermore, antioxidant capacities (DPPH, ABTS, FRAP), phenolic, and flavonoid contents were determined. According to the results obtained in the agar well diffusion test, the highest value was observed in the onion extract of the plant against Neisseria meningitidis bacteria (19.2 mm zone diameter). No antimicrobial effect was observed in the flower and stem. All AgNP-coated extracts generally showed antimicrobial activity. The highest effect was again detected in Neisseria meningitidis in the onion-AgNP extract (15.4 mm zone diameter). The analysis performed with the penicillin combination of the extracts showed the highest antimicrobial effect in Pseudomonas aeruginosa (26.26 mm zone diameter). According to the antioxidant capacity results, the highest value was determined in the flower (ethanol)-AgNP extract in the DPPH analysis, and in the flower ethanol extract in the ABTS and FRAP analyses. The highest value for total phenolic and flavonoid content was again found in the flower (ethanol)-AgNP extract. In conclusion, coating F. imperialis extract with AgNP has increased its antimicrobial and antioxidant effects, eliminated resistant bacteria, and been found to support the drug with a synergistic effect when antibiotics are insufficient, as well as having beneficial effects on health. More preclinical studies are needed to thoroughly investigate the other effects of this plant on human health.