MICROBIAL SYNTHESIS OF SILVER NANOPARTICLES (AG-NP) AND THEIR BIOLOGICAL ACTIVITIES

Nanobiotechnology, which deals with

nanoparticles (NPs), has been one of the most popular topics in recent years. NPs

are small materials ranging between 1 to 100 nanometers (nm) in size. They have

higher surface reactivity than their bulk materials and therefore, have

different properties and application areas. Although NPs

can also be synthesized by physical and chemical means, their biological

synthesis is preferred due to their toxicity and incompatibility issues. Green

synthesis of nanoparticles by bacteria offers a simple, cheap, and ecologically

friendly ways. <o:p></o:p>

Antibiotic resistance

of pathogenic bacteria is a serious problem worldwide and novel

and potent bactericidal agents is of great importance.

In this study, silver nanoparticles (Ag-NPs) were synthesized by Pseudomonas aeruginosa

strain OG1 strain in nutrient broth medium containing 1 mM AgNO3.

They were analyzed by SEM, TEM and XRD and were found to be 30 nm in size. <o:p></o:p>

Ag-NPs were used

for their antibacterial, antibiofilm and antiurease activities. Growth

inhibition zones of 0,8 mm and 1.1 mm with 100 µg/mL and 200 µg/mL Ag-NPs,

respectively, were obtained against Streptococcus

salivarius. While 100 and 200 µg/mL Ag-NP caused complete urease inhibition

(100%) in S. salivarius in the first

5 hours and 24 h incubation. 86 % and 90% inhibitions in biofilm formation were

observed with 100 µg/mL and 200 µg/mL Ag-NP, respectively. As a result, this

study showed that Ag-NPs can be used as effective antibacterial, antibiofilm

and antiurease agents against microorganisms that may be harmful to humans.<o:p></o:p>