Exploring the biosynthesized gold nanoparticles for their antibacterial potential and photocatalytic degradation of the toxic water wastes under solar light illumination

Gold NPs were biosynthesized using the extracellular cell free filtrate of fungus Glomus aureum and were used for their anti-bacterial potential and photocatalytic degradation of methyl orange dye. Different types of analytical techniques were employed for determination of purity, composition and morphology of the biosynthesized gold NPs. The functional groups and elemental contents of the biosynthesized gold NPs were determined through FTIR and EDX, respectively. The biosynthesized gold NPs exhibited significant antibacterial activity with zones of inhibition of 20 and 19 mm against Acinetobacter baumannii and Proteus mirabilis, respectively. The minimum inhibitory concentration (MICs) values of the biosynthesized gold NPs against A. baumannii and P. mirabilis were 32 and 28 μg/mL, respectively. The increased leakage of the intracellular constituents from the bacterial cells suggested that the biosynthesized gold NPs probably acted upon the cell membrane by interaction with the membrane lipid and protein. The biosynthesized gold NPs could be used as a photo catalyst for the degradation of methyl orange dye under solar light illumination showing excellent photocatalytic activity of 45% for methyl orange dye in 6 h. These findings suggested that biosynthesized gold NPs could be used as a promising candidate for the clinical development of treatment of bacterial pathogenesis and as an efficient photo catalyst for the removal of toxic water pollutants. [Display omitted] •Cell free filtrate of Glomus aureum has greater ability to biosynthesized AuNPs.•Biosynthesized AuNPs have outstanding antibacterial potential.•The MIC values of the biosynthesized AuNPs were also very significant.•Bactericidal action of AuNPs was due to damaging the bacterial membrane.•Biosynthesized AuNPs have ability to degrade methyl orange under solar illumination.