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activities like dehydrogenase, phosphates, urease, nitrogen fixation, and ammonia
oxidation. Therefore, we reviewed the effect of different types of engineered nanomaterials such as silver, zinc oxide, copper oxide, titanium oxide, iron, and carbonbased nanomaterial on the microbial community structure, which is needed for the
harmonization of soil and water ecosystem. Silver, copper, and carbon-based nanomaterial have been studied broadly in terms of toxicity to microbial communities.
The toxicity level of various nanomaterials depends on nanomaterial concentration
and structure of exposed microbial community. The mechanism of nanomaterial
toxicity to microbial enzymatic activities, role of nanomaterials in reactive oxygen
species generation, and their impact on microbial reduction have been discussed in
the chapter.
Keywords Microbial community · Nanomaterial · Nano-toxicity · ROS · Enzyme
4.1 Introduction
Microbes are the most important component of ecosystem, which play a significant
role in different biogeochemical cycles, climate regulation, and plant productivity.
The diversity of microbial community disturbed by changes in the surrounding
environment such as increasing in organic or inorganic components, temperature,
pH and water, which effect the expression of enzyme and their activity.
In the current decade, the application of metal nanoparticles is expanding in agriculture, medicine, food industry, electrical and electronics, and nanotechnologybased consumer products are increasing. Simultaneously, the demand of
nanomaterial production increased with time. It was predicted that about 58,000
tons of engineered nanomaterials have been produced by 2020 (Maynard et al.
2006). The synthesized nanomaterials are released into environment from various
industries or through anthropogenic activities, for example, zinc oxide (ZnO) and
titanium oxide (TiO 2 ) nanoparticles have been released indirectly through the use of
ZnO- and TiO 2 -containing sunscreens and cosmetic products. Similarly, silver
nanoparticles are released from washing textile industries, and TiO 2 nanoparticles
are released from paint industries. Uses of nanoparticle-containing fertilizer and
pesticides also contaminate the soil and water bodies (Osmond and Mccall 2010;
Kaegi et al. 2010; Lorenz et al. 2012; Nowack et al. 2012).
The release of excess nanomaterial in the environment affects the different components of the ecosystem, and microbes are one of them. The shape, size, surface
chemistry of nanoparticles, and chemical composition are the major characteristics
of metal nanoparticles which are responsible for biological interactions (Sinha and
Khare 2013). Characteristics such as nanoscale size and high surface to volume
ratio of nanomaterials make them highly active on the basis of their ionization
nature. The released nanomaterials interact with the microbial communities residing in different habitats such as soil, water, and air and show toxicity to them.
Different types of nanomaterials have been reported, such as silver nanoparticles
H. Chhipa
activities like dehydrogenase, phosphates, urease, nitrogen fixation, and ammonia
oxidation. Therefore, we reviewed the effect of different types of engineered nanomaterials such as silver, zinc oxide, copper oxide, titanium oxide, iron, and carbonbased nanomaterial on the microbial community structure, which is needed for the
harmonization of soil and water ecosystem. Silver, copper, and carbon-based nanomaterial have been studied broadly in terms of toxicity to microbial communities.
The toxicity level of various nanomaterials depends on nanomaterial concentration
and structure of exposed microbial community. The mechanism of nanomaterial
toxicity to microbial enzymatic activities, role of nanomaterials in reactive oxygen
species generation, and their impact on microbial reduction have been discussed in
the chapter.
Keywords Microbial community · Nanomaterial · Nano-toxicity · ROS · Enzyme
4.1 Introduction
Microbes are the most important component of ecosystem, which play a significant
role in different biogeochemical cycles, climate regulation, and plant productivity.
The diversity of microbial community disturbed by changes in the surrounding
environment such as increasing in organic or inorganic components, temperature,
pH and water, which effect the expression of enzyme and their activity.
In the current decade, the application of metal nanoparticles is expanding in agriculture, medicine, food industry, electrical and electronics, and nanotechnologybased consumer products are increasing. Simultaneously, the demand of
nanomaterial production increased with time. It was predicted that about 58,000
tons of engineered nanomaterials have been produced by 2020 (Maynard et al.
2006). The synthesized nanomaterials are released into environment from various
industries or through anthropogenic activities, for example, zinc oxide (ZnO) and
titanium oxide (TiO 2 ) nanoparticles have been released indirectly through the use of
ZnO- and TiO 2 -containing sunscreens and cosmetic products. Similarly, silver
nanoparticles are released from washing textile industries, and TiO 2 nanoparticles
are released from paint industries. Uses of nanoparticle-containing fertilizer and
pesticides also contaminate the soil and water bodies (Osmond and Mccall 2010;
Kaegi et al. 2010; Lorenz et al. 2012; Nowack et al. 2012).
The release of excess nanomaterial in the environment affects the different components of the ecosystem, and microbes are one of them. The shape, size, surface
chemistry of nanoparticles, and chemical composition are the major characteristics
of metal nanoparticles which are responsible for biological interactions (Sinha and
Khare 2013). Characteristics such as nanoscale size and high surface to volume
ratio of nanomaterials make them highly active on the basis of their ionization
nature. The released nanomaterials interact with the microbial communities residing in different habitats such as soil, water, and air and show toxicity to them.
Different types of nanomaterials have been reported, such as silver nanoparticles
H. Chhipa