Gold has a rich coordination and organometallic chemistry,
Haruta et al. (1987) first reported on the oxidation of CO at low
temperature using supported gold nanoparticles (3–5 nm).
Supported gold nanoparticles are also used as heterogeneous catalysts
in the degradation and mineralization of the harmful organic
pollutants in the water, air and some advantageous reactions
(Ayati et al., 2014). Methylene blue (MB) is a blue cationic azo
dye, which absorbs light at visible spectrum around 664 nm in
an oxidizing environment
(XRD) analysis. This facile intracellular synthesis of gold nanoparticles by a mushroom without using
any toxic chemicals or technologically expensive processes is used as a heterogeneous catalyst in the
reduction of organic pollutants methylene blue (MB) and 4-nitrophenol (4NP). The reduction reaction follows
pseudo-first order kinetics with a reaction rate constant of 0.0529 min1 and 0.1236 min1 for MB
and 4NP, respectively. This biological process of biomatrixing of metal nanoparticles for heterogeneous
catalytic reactions is simple, nontoxic, environmentally benign, and economically viable compared to
the chemical synthetic routes.