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bioRxiv · 10.1101/2025.01.21.634070

Green Synthesis of Silver Nanoparticles Using Sudanese Candida parapsilosis: A Sustainable Approach to Combat Antimicrobial Resistance

Ibrahim, N. A. A.·Saeed, H. A.·Saeed, S. M.·Mohamed, O.·Ibrahim, S. A. E.·Mohamed, S. B.
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Abstract

BackgroundAntimicrobial resistance (AMR) is a major global health threat, particularly in Sudan, where the overuse and misuse of antibiotics have led to the emergence and spread of multidrug-resistant (MDR) pathogens. Traditional methods to address AMR often fail to provide sustainable solutions. Nanotechnology offers promising alternatives, with silver nanoparticles (AgNPs) demonstrating broad-spectrum antimicrobial properties. This study aims to develop an eco-friendly synthesis of AgNPs using Candida parapsilosis isolated from Sudanese soil, leveraging untapped fungal biodiversity to combat AMR. ResultsThe Candida parapsilosis-mediated synthesis of AgNPs was successfully characterized using UV-Vis spectroscopy, X-ray diffraction (XRD), and high-resolution transmission electron microscopy (HRTEM), confirming the formation of well-defined nanoparticles. The biosynthesized AgNPs exhibited potent antimicrobial activity against Gram-positive and Gram-negative MDR pathogens. Medium concentrations of AgNPs demonstrated optimal activity, with inhibition zones up to 29 mm for Pseudomonas aeruginosa (ATCC27853). MIC and MBC assays revealed AgNPs bactericidal efficacy, particularly against Escherichia coli and Klebsiella pneumoniae at 0.3125 mg/mL. Synergistic effects with antibiotics, such as ceftazidime and colistin, significantly enhanced antimicrobial activity, with fold increases up to 9.46. AgNPs disrupted bacterial membranes, as evidenced by increased permeability and leakage of nucleic acids. ConclusionsThis study presents a novel and sustainable approach to combating AMR by utilizing Sudanese fungal strains for the green synthesis of AgNPs. The findings highlight the potential of AgNPs as an effective antibacterial agent, particularly in combination with conventional antibiotics, to combat multidrug-resistant pathogens. This research not only offers a cost-effective and environmentally friendly solution to AMR but also underscores the significant potential of integrating microbiology and nanotechnology to address global health challenges. The results could pave the way for future applications in both public health and environmental sustainability.

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Ibrahim, N. A. A., Saeed, H. A., Saeed, S. M., Mohamed, O., Ibrahim, S. A. E., Mohamed, S. B.. 2025-01-22. Green Synthesis of Silver Nanoparticles Using Sudanese Candida parapsilosis: A Sustainable Approach to Combat Antimicrobial Resistance. https://doi.org/10.1101/2025.01.21.634070

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