Antibacterial Activities of Biosynthesized Silver-Nanoparticles from Three Species of Mushroom

Abstract

Nanoparticles are particles of less than 100 nm in diameter that exhibit new or enhanced size-dependent properties compared
with bigger particles of similar material. In this study, AgNPs were synthesized using three mushroom species- Lentinus
squarrosulus, Ganoderma lucidum, and Pleurotus tuberregium. The formation of AgNPs was observed using a UV-light
spectrophotometer. The functional groups present were identified by Fourier transform infrared spectroscopy; while size and
surface morphology were also analyzed using scanning electron microscopy. The study revealed that the AgNPs were highly
aggregated crystalline spherical nanoparticles with most of them irregular in shape. The cubic structure of AgNPs was identified
using the X-ray Diffraction analysis with peaks for Lentinus squarrosulus at 2θ = 28.5o and 21.8o, 8o and 44o for Ganoderma
lucidum, and 39o and 26o for Pleurotus tuberregium (corresponding to the planes of silver 111, 200 respectively). Antibacterial
analyses from the three mushrooms showed that the biosynthesized AgNPs possess antibacterial activity (against Staphylococcus
aureus, Escherichia coli, Bacillus sp, and Pseudomonas aeruginosa). The antibacterial activities of each mushroom species were
compared with three antibiotics- Chloramphenicol, Ciprofloxacin and Streptomycin. The study revealed that the AgNPs of
Pleurotus tuber-regiumexhibited a broader antibacterial activity compared to the Lentinus squarrosulus and Ganoderma lucidum.