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E. A. Adebayo et al.
size and density of dislocation. Also, in the XRD analysis, strain increased with
increase in P. ostreatus extract concentration. Furthermore, P. ostreatus-mediated
zinc sulphide nanoparticles have found applications in several industrial processes
mainly in coating surfaces. Iron nanoparticles have been produced using mushrooms,
most especially diverse species of Pleurotus with the secretion of the nanoparticles
detected at wavelength of 226–276 nm where siderophore was important in the
transportation of iron within the mycelium (Mazumdar and Haloi 2011). Other fungi
have been employed in iron nanoparticles synthesis; however, there is no recent
information on mushroom-mediated iron nanoparticles; hence, this is an emerging
field of mushroom nanobiotechnology requiring more research. Faraji et al. (2010)
reported the potentials of synthesizing more metallic nanoparticles from mushrooms
and in the world today. The synthesis of copper oxide, aluminium oxide, magnesium oxide nanoparticles among others is gradually gaining attentions in mushroom
nanobiotechnology (Table 1).
5 Mechanism of Mushroom-Mediated Nanoparticles
Synthesis
Light sensitivity and water solubility are the two important criteria in the green
synthesis of nanoparticles, and interestingly, mushrooms contain compounds such
as riboflavin that possess these characteristics. Mushroom riboflavin acts as enzyme
in redox reactions when in the form of flavin adenine dinucleotide (FAD) and as
bound coenzyme when in form of flavin mononucleotide (FMN). Furthermore, the
common result of degradation of riboflavin and its derivatives in FMN and FAD
in the presence of light is lumiflavin. Thus, in mushroom nanobiotechnology, ions
of metals are reduced to nanoparticles due to the presence of flavo proteins, also
known as flavin in the mushroom extracts. In the process of nanoparticles synthesis
with mushroom, photons of energy are absorbed in the presence of sunlight which
consequently excite the flavin which is abundant in several mushroom species to
donate electrons or act as oxidizing agent important in nanoparticles production (Bhat
et al. 2011) (Fig. 2). Flavonoids have been demonstrated for the green synthesis of
nanoparticles (Sathishkumar et al. 2018).
Generally, several studies have strongly linked the mechanism of mushroom
nanoparticles biosynthesis to the presence of important metal-reducing enzymes in
mushroom species that catalyse the production of nanometric elemental metal from
metal ions. According to Ahmad et al. (2003), biosynthesis of mushroom-mediated
nanoparticles is marked with clear colour change and optical properties alteration as
determined by resonance bands of surface plasmon in UV–vis spectroscopy. In addition, several factors have been known to influence mushroom nanoparticles biosynthesis and some of these factors that have been extensively discussed in literature
include the species of the mushroom and certain characteristics of the mushroom
such as capping, temperature, medium of dispersion and pH (Khandel and Shahi
E. A. Adebayo et al.
size and density of dislocation. Also, in the XRD analysis, strain increased with
increase in P. ostreatus extract concentration. Furthermore, P. ostreatus-mediated
zinc sulphide nanoparticles have found applications in several industrial processes
mainly in coating surfaces. Iron nanoparticles have been produced using mushrooms,
most especially diverse species of Pleurotus with the secretion of the nanoparticles
detected at wavelength of 226–276 nm where siderophore was important in the
transportation of iron within the mycelium (Mazumdar and Haloi 2011). Other fungi
have been employed in iron nanoparticles synthesis; however, there is no recent
information on mushroom-mediated iron nanoparticles; hence, this is an emerging
field of mushroom nanobiotechnology requiring more research. Faraji et al. (2010)
reported the potentials of synthesizing more metallic nanoparticles from mushrooms
and in the world today. The synthesis of copper oxide, aluminium oxide, magnesium oxide nanoparticles among others is gradually gaining attentions in mushroom
nanobiotechnology (Table 1).
5 Mechanism of Mushroom-Mediated Nanoparticles
Synthesis
Light sensitivity and water solubility are the two important criteria in the green
synthesis of nanoparticles, and interestingly, mushrooms contain compounds such
as riboflavin that possess these characteristics. Mushroom riboflavin acts as enzyme
in redox reactions when in the form of flavin adenine dinucleotide (FAD) and as
bound coenzyme when in form of flavin mononucleotide (FMN). Furthermore, the
common result of degradation of riboflavin and its derivatives in FMN and FAD
in the presence of light is lumiflavin. Thus, in mushroom nanobiotechnology, ions
of metals are reduced to nanoparticles due to the presence of flavo proteins, also
known as flavin in the mushroom extracts. In the process of nanoparticles synthesis
with mushroom, photons of energy are absorbed in the presence of sunlight which
consequently excite the flavin which is abundant in several mushroom species to
donate electrons or act as oxidizing agent important in nanoparticles production (Bhat
et al. 2011) (Fig. 2). Flavonoids have been demonstrated for the green synthesis of
nanoparticles (Sathishkumar et al. 2018).
Generally, several studies have strongly linked the mechanism of mushroom
nanoparticles biosynthesis to the presence of important metal-reducing enzymes in
mushroom species that catalyse the production of nanometric elemental metal from
metal ions. According to Ahmad et al. (2003), biosynthesis of mushroom-mediated
nanoparticles is marked with clear colour change and optical properties alteration as
determined by resonance bands of surface plasmon in UV–vis spectroscopy. In addition, several factors have been known to influence mushroom nanoparticles biosynthesis and some of these factors that have been extensively discussed in literature
include the species of the mushroom and certain characteristics of the mushroom
such as capping, temperature, medium of dispersion and pH (Khandel and Shahi