Green Synthesis of Silver Nanoparticles from Macrocybe gigantea and its Effect Against Food Borne Pathogens

Abstract

Objectives: To evaluate the efficacy of edible mushroom, Macrocybe gigantea for the biosynthesis of silver nanoparticles, antioxidant property and antibacterial property. Methods: M. gigantea pure culture was isolated using tissue culture in a petri-plate comprising potato dextrose agar (PDA) medium, spawn was prepared using sorghum grains and mushrooms were grown indoors using paddy straw in an uniquely designed environment for mushroom growth. The green synthesis of silver nanoparticles with AgNO 3 , antioxidant activity and antibacterial potential against a few food-borne bacteria were all investigated. The formation of AgNPs was further confirmed using a UV-Visible spectrophotometer. The silver nanoparticles were examined using Fourier-transform infrared spectroscopy (FTIR) and Scanning Electron Microscopy (SEM). The disc diffusion method was used to test the bacteriostatic and bactericidal activity of synthesised silver nanoparticles against selected food-borne bacteria such as Escherichia coli, Bacillus subtilis and Streptococcus mutans. Findings: The existence of phytochemicals such as alkaloids, terpenoids, phenols, flavonoids, proteins, and carbohydrates was revealed. Furthermore, the AgNPs produced from M.gigantea demonstrated absorbance at 420nm in a UV-Visible spectrophotometer. According to the SEM pictures, AgNPs appear spherical with diameters ranging from 50 to 70nm. At 100g/mL, the DPPH antioxidant assay exhibited the maximum percentage of inhibition of 67.94%, with an IC50 value of 57.07g/mL. The produced AgNPs also inhibited bacterial growth significantly. Green synthesised AgNPs from M.gigantea were produced in an environmentally friendly, quick and simple technique that functions as an antibacterial agent against certain food-borne pathogens such as E. coli, Bacillus subtilis, and Streptococcus mutans. The antibacterial screening demonstrates the biocidal ability of AgNPs from M.gigantea, which could be employed in the food processing and packaging industries. Novelty: This study is regarded as the first attempt to synthesise AgNPs from M.gigantea for use against food-borne bacteria.