Biosynthesis of Silver Nanoparticles using Edible Mushrooms and It’s Bactericidal Activities

Mushrooms are called "Food of God" by the Romans. It contain about 85-95% water, 3% protein, 4% carbohydrates, 0.1% fats, 1% minerals, vitamins and appreciable amount of potassium, phosphorus, copper and iron but low level of calcium. Silver nanoparticles play a significant role in the field of biology and medicine by Drug and gene delivery, Bio detection of pathogens, Detection of proteins, Probing of DNA structure, Tissue engineering, Tumour destruction via heating (hyperthermia), Separation and purification of biological molecules and cells. Biosythesis of silver nanoparticles (AgNPs) by using mushrooms are eco-friendly and non-toxic. In the present study, we have reported the biological synthesis of silver nanoparticles (AgNPs) by using edible mushrooms extract such as Agaricusbisporus, Calocybaeindica, Pleurotusflorida, and Pleurotusostreatusas a bioreductant and antibiotic against some bacteria. The fresh and dry mushroom species were screened for the production of silver nanoparticles and it was confirmed from color change from light yellow to reddish brown by challenging the mushroom extract with 1mm silver nitrate within few minutes of photo-irradiation (exposed to light). UV visible studies indicated the surface Plasmon resonance at 300nm which depicts the formation of silver nanoparticles. FTIR studies showed the presence of functional groups involved in the reduction of silver nitrate to silver ions. The anti-bacterial activity was studied in Agaricusbisporus, Calocybaeindica, Pleurotusflorida, and Pleurotusostreatus against Escherichia coli, Staphylococcus aureus, and Pseudomonas aeruginosa along with standard antibiotic such as streptomycin, ampicillin and tetracycline. The silver nanoparticles of Agaricusbisporus, Calocybaeindica, Pleurotusflorida, and Pleurotusostreatus was found to have wider antibacterial activity in all bacterial cultures. The maximum zone of inhibition was observed in Staphylococcus aureus (21mm and 19mm) by the mushroom Agaricusbisporusand Pleurotusflorida. In positive and negative control there was no zone formation in all bacterial strains. The high bactericidal activity is certainly due to the silver cations released from AgNP's that act as reservoirs for the Ag+ bactericidal agent.