Master’s Discussion
The College of Science for Women at the University of Baghdad examined a master’s thesis entitled “In- Vitro, Evaluation the Effect of Silver Nanoparticles Capping by pyocyanin as Anticandida Agents Against Clinical Isolates Of Candida Species” presented by the postgraduate student Huda Ali Hameed, as a requirement for the degree of Master of Science in Biology/Microbiology. The study was supervised by Asst. prof.Dr. Nada Sabah Razouqi.
This study involved obtaining clinical isolates of Candida albicans from various samples collected from both genders and different age groups. Isolates of Pseudomonas aeruginosa were also isolated and identified. Two types of nanoparticles were used: silver nanoparticles (AgNPs) and AgNPs coated with pyocyanin extract (PCN-AgNPs) obtained from a highly productive P. aeruginosa isolate, where pyocyanin production reached 10.7 μg/ml under optimal production conditions.
The effect of the colloidal solutions of both AgNPs and PCN-AgNPs was evaluated separately against C. albicans using the Agar Well Diffusion method and the Microtiter Plate (MTP) method. The minimum inhibitory concentration (MIC) of PCN-AgNPs was determined to be 2.33 μg/ml against resistant isolates, compared to the effect of non-coated pyocyanin (PCN), which recorded 3.44 μg/ml. This indicates the effectiveness of the prepared nanoparticles in inhibiting the growth of C. albicans and reducing its virulence factors, such as protease production and biofilm formation, in tests performed on seven isolates. The results showed varying degrees of reduction in protease production and biofilm formation before and after treatment with the nanoparticles. Additionally, the extracted pyocyanin was characterized and its biological activity tested before being used in subsequent experiments through GC-MS analysis. To characterize pyocyanin, the prepared silver nanoparticles, and the pyocyanin-coated silver nanoparticles, several analytical techniques were employed, including TEM, XRD, FE-SEM, FTIR, UV–vis, and AFM. The results showed that the pyocyanin-coated silver nanoparticles were chemically stable, highly crystalline, spherical in shape, and had a maximum grain size of 80.72 nm.
The study recommends conducting future experiments to determine the effect of these synthesized nanoparticles combined with pyocyanin dye on the gene expression of virulence factors in resistant Candida albicans. It also recommends exploring the possibility of using purified active compounds of pyocyanin in other nanotechnology applications, such as food preservation.
Very Good.
