Synthesis of silver nanoparticles from summer snowflake plant (Leucojum aestivum L.) and determination of biological activities

Türkmen N, Synthesis of Silver Nanoparticles from Summer Snowflake Plant (Leucojum aestivum L.) and Determination of Biological Activities, Van Yüzüncü Yıl University, Institute of Health Sciences, Department of Basic Pharmacy Sciences, Master of Sciences Thesis, Van, 2024. The aim of this study was to obtain silver nanoparticles (La-AgNPs) from Leucojum aestivum L. (summer snowflake) plant by green synthesis method, characterization and investigation of their biological activities. In the study, La-AgNPs were synthesized using the infusion obtained from L. aestivum bulbs. Synthesis parameters (temperature, silver nitrate concentration, extract concentration, pH and time) were optimized. The obtained nanoparticles were characterized by UV-Vis spectrophotometry, FTIR, SEM and Zeta Sizer analysis. The phenolic content of the plant was analyzed by HPLC. The antimicrobial activity of La-AgNPs was evaluated by minimum inhibition concentration (MIC) and bactericidal activity tests against gram-positive and gram-negative bacteria. Cytotoxicity and anticancer effects were studied on MRC-5 and CaCo-2 cell lines. The results showed that the optimum synthesis conditions of La-AgNPs were 2 mM AgNO3, 15% extract concentration, 40°C reaction temperature, pH 9 and 10 min reaction time. Characterization studies revealed that the nanoparticles had spherical morphology and the average size was 74.7 nm. HPLC analysis showed the presence of phenolic compounds such as gallic acid, catechin, ascorbic acid and quercetin in the extract. La-AgNPs exhibited varying degrees of antimicrobial activity against all tested bacterial species. In cytotoxicity tests, La-AgNPs showed minimal effect on normal cells in the tested concentration range (1.5-12 μg/mL), but no significant anticancer effect at the tested concentrations. This study demonstrated that silver nanoparticles from L. aestivum plant can be used as potential antimicrobial agents, but further research is required for anticancer applications.