Environmental Nanobiotechnology: Microbial-Mediated …
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Also, these cellulose-rich materials could be used as feedstock for the production
of many beneficial products such as biofuel, single cell protein, chemicals, organic
fertilizers and animal feeds (Hasanin et al. 2019). Successful degradation of celluloserich wastes using cellulases into fermentable sugars is the basis for further conversion into beneficial products (Darwesh et al. 2020b). However, production of celluloses could be a cost-effective process especially when the enzymes could not be
reused for further degradation cycles. Given that, the immobilization of enzymes,
including celluloses, enables the multiple utilization of enzymes in several cycles;
so the improvement of immobilization process will enhance the overall process.
Nanomaterials especially magnetic NPS are considered as the most promising
materials for enzymes immobilization due to enabling the recycling of enzymes,
enhancement of enzyme stability and storage efficiency. Sustainability behind the
second biofuel generation from lignocellulosic biomass could be increased with the
sustainability of degrading enzymes stability and reusing with the aid of magnetic
nanoparticles. Furthermore, nanoparticles could be applied as catalyst for pretreatment for enzyme reaction related to waste recycling, e.g., the application of iron oxide
nanoparticle and acidic pretreatment for corn stover and subsequent degradation into
fermentable sugars (Srivastava et al. 2017; Darwesh et al. 2019b).
4.4 Application of Biogenic NPs as Nanocatalysts
Catalysts accelerate the chemical reaction by forming bonds with the molecules of
reactants to form the “product(s)” and detached from the final product to be available for another reaction cycle(s). Catalysts could be atoms, molecules and solid
surfaces as well as biological enzymes. Catalysts are very important for industrial
chemical transformations (considered as the workhorses in many industries) where
about 85–90% of chemical industry products are produced by catalytic reactions.
Without catalysts, many medical and essential chemical products “would not be
feasible” while another products will cost more time, reaction temperature and reactants as well as generate more wastes (Singh and Tandon 2014; Chorkendorff and
Niemantsverdriet 2017). This may mean, in other words, that “without catalysts,
humanity and the environment together will cost more.”
Nanocatalysts are catalytic materials that “have at least nanoscale dimension,
either externally or in terms of internal structures” (Saoud 2018). Hence, application of nanotechnology in catalysts could be either by manufacturing nano-sized
particles as “heterogeneous catalysis” or incorporation of synthetic nanoparticles
with enzymes to enhance or keep their activities or enable its reuse (e.g., magnetic
NPs). For instance, the esterification reaction to convert fatty acids using methanol
into fatty acid methyl ester (biodiesel) could be performed in the presence of an
homogeneous catalyst (either acidic, alkaline or enzyme) or with the aid of heterogeneous solid catalyst (El-Baz et al. 2016; Saoud 2018). Some magnetic nanocatalysts such as CaO/KOHFe 3 O 4 and KF/KOH-Fe 3 O 4 have been reported by Farrokheh
et al. (2020) as promising heterogeneous nanocatalysts to produce biodiesel from
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Also, these cellulose-rich materials could be used as feedstock for the production
of many beneficial products such as biofuel, single cell protein, chemicals, organic
fertilizers and animal feeds (Hasanin et al. 2019). Successful degradation of celluloserich wastes using cellulases into fermentable sugars is the basis for further conversion into beneficial products (Darwesh et al. 2020b). However, production of celluloses could be a cost-effective process especially when the enzymes could not be
reused for further degradation cycles. Given that, the immobilization of enzymes,
including celluloses, enables the multiple utilization of enzymes in several cycles;
so the improvement of immobilization process will enhance the overall process.
Nanomaterials especially magnetic NPS are considered as the most promising
materials for enzymes immobilization due to enabling the recycling of enzymes,
enhancement of enzyme stability and storage efficiency. Sustainability behind the
second biofuel generation from lignocellulosic biomass could be increased with the
sustainability of degrading enzymes stability and reusing with the aid of magnetic
nanoparticles. Furthermore, nanoparticles could be applied as catalyst for pretreatment for enzyme reaction related to waste recycling, e.g., the application of iron oxide
nanoparticle and acidic pretreatment for corn stover and subsequent degradation into
fermentable sugars (Srivastava et al. 2017; Darwesh et al. 2019b).
4.4 Application of Biogenic NPs as Nanocatalysts
Catalysts accelerate the chemical reaction by forming bonds with the molecules of
reactants to form the “product(s)” and detached from the final product to be available for another reaction cycle(s). Catalysts could be atoms, molecules and solid
surfaces as well as biological enzymes. Catalysts are very important for industrial
chemical transformations (considered as the workhorses in many industries) where
about 85–90% of chemical industry products are produced by catalytic reactions.
Without catalysts, many medical and essential chemical products “would not be
feasible” while another products will cost more time, reaction temperature and reactants as well as generate more wastes (Singh and Tandon 2014; Chorkendorff and
Niemantsverdriet 2017). This may mean, in other words, that “without catalysts,
humanity and the environment together will cost more.”
Nanocatalysts are catalytic materials that “have at least nanoscale dimension,
either externally or in terms of internal structures” (Saoud 2018). Hence, application of nanotechnology in catalysts could be either by manufacturing nano-sized
particles as “heterogeneous catalysis” or incorporation of synthetic nanoparticles
with enzymes to enhance or keep their activities or enable its reuse (e.g., magnetic
NPs). For instance, the esterification reaction to convert fatty acids using methanol
into fatty acid methyl ester (biodiesel) could be performed in the presence of an
homogeneous catalyst (either acidic, alkaline or enzyme) or with the aid of heterogeneous solid catalyst (El-Baz et al. 2016; Saoud 2018). Some magnetic nanocatalysts such as CaO/KOHFe 3 O 4 and KF/KOH-Fe 3 O 4 have been reported by Farrokheh
et al. (2020) as promising heterogeneous nanocatalysts to produce biodiesel from