Biogenic synthesis of different forms of bio-caped silver nanoparticles using Microcystis sp. and its antimicrobial activity

aims: Isolation of cyanobacterium from local habitat, molecular identification, synthesis of nanoparticles with different forms, antimicrobial estimation background: Nanobiotechnology is the most advanced and cutting-edge discipline of biotechnology; creating nanoparticles using cyanobacteria is a highly efficient and reliable method. Researchers are looking forward to synthesizing new antimicrobials due to the high resistance bacteria obtain against antibiotics daily objective: This study focused on the biosynthesis of silver nanoparticles by different biological methods from the isolated Microcystis sp. from the Beni-Suef area to be utilized as an antimicrobial agent. method: Microcystis sp. demonstrated a greater efficiency in metal reduction, specifically using the direct strain powder method, ethanolic extract pellets, and ethanolic extract. result: The biogenic AgNPs were found in different forms as cubic, spherical, and rod-shaped. UV-Vis detected the peak at a range of 420 nm, while FTIR was utilized to detect the bio-functional groups of the reduction Ag+ especially phenolic. Furthermore, Zeta-sizer detected the size and potential of polydisperse particles. SEM detected the morphological characteristics of AgNPs with the bio-caped layers at the range of 40-130nm. Antibacterial activity was tested against Gram-positive and Gram-negative bacteria and antifungal activity. Staphylococcus sp. showed a best clear zone of 32 mm with AgNPs from the pellet method. The less active one is the larger cubic AgNPs prepared by the powder method, implying that the larger particles are less effective as antibacterial agents. conclusion: Silver nanoparticles were produced using eco-friendly techniques. To prevent aggregation, the cyanobacterium Microcysts sp. powder, pellets, and ethanol extract were utilized as reducing and capping agents. Cubic, spherical, and rod shapes with diameters ranging from 40nm to 130nm were discovered using SEM. According to our research, cubic nanoparticles are more effective in killing germs than spherical ones. Our AgNPs had a broad spectrum of antibacterial action, but they were particularly effective against fungi and Gram-positive bacteria, particularly those belonging to the genera Staphylococcus sp. other: NA