Nanotechnology in Bioprocess Development …
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application of biocatalysts such as nano-sized biocatalysts (Kim et al. 2016; Faloye
et al. 2014; Sewsynker et al. 2015; Sewsynker-Sukai and Gueguim-Kana 2018).
The use of nano-sized materials has attracted significant attention in the recent
decades due to intrinsic properties that promote its application in several biotechnological fields such as bioprocessing, agriculture, biosensor, biopharmaceuticals and
medicine (Lateef et al. 2018; Elegbede and Lateef 2019a, b; Sekoai et al. 2019). More
specifically, nanotechnology has been employed in various bioprocesses to improve
the microbial metabolic activities by their integration with metabolic intermediates
and key enzyme activities. Consequently, increased glycolytic rates, cell-substrate
affinity, growth rate, mass transfer rate, modulation of oxidation–reduction potential (ORP) enhanced process performance and ultimately high product yields. This
chapter focuses on the recent progress made in the application of nanotechnology
for the enhancement of biofuel production processes. Furthermore, the impacts
of nanoparticles as biocatalytic additives in biodiesel, bioethanol, biohydrogen,
biomethane and biogas production are reviewed. Finally, the current challenges and
future outlook on the application of nanotechnology in biofuel production processes
are highlighted.
2 The Use of Nanotechnology in Biofuel Production
In the recent years, nanoparticles have attracted significant attention due to its distinctive physical and chemical nature that has shown to stimulate microbial and enzymatic biochemical activities in biofuel production. Previous studies have indicated
that the stimulatory and catalytic properties of nanoparticles are majorly influenced
by their shape, size, concentration, surface coating and operating conditions (Resham
and Priyabrata 2008). The use of biocompatible and bioactive nanomeric additives
such as NiO, Fe 3 O 4 and AgO nanoparticles in biofuel production processes that could
significantly improve bioprocess performance and productivity is being implemented
(Abdelsalam et al. 2016). Nanoparticle surface properties can regulate stability, solubility and targeting of specific cellular receptors (Howarth et al. 2008). Moreover,
the suitability of nanoparticle additives is strongly dependent on other factors such
as operating parameters, the type of substrate and additive type (Abdelsalam et al.
2016). For instance, monovalent and functionalized nanomaterial might be used to
stimulate or regulate the activities of individual proteins or enzymes (Fu et al. 2004;
Howarth et al. 2008). More specifically, for biological applications, the surface property is generally polar, which gives high aqueous solubility that prevents nanoparticles
aggregation and ultimately, their performance (Prime and Whitesides 1991; Liu et al.
2010).
Nanomaterials can also play a vital role to improve the thermal and pH stability
of enzymes (Pandurangan and Kim 2015). Furthermore, a coated nanoparticle
that is multivalent or polymeric confers high stability. Multivalent nanoparticles,
bearing multiple targeting groups, can cluster receptors, which could activate cellular
167
application of biocatalysts such as nano-sized biocatalysts (Kim et al. 2016; Faloye
et al. 2014; Sewsynker et al. 2015; Sewsynker-Sukai and Gueguim-Kana 2018).
The use of nano-sized materials has attracted significant attention in the recent
decades due to intrinsic properties that promote its application in several biotechnological fields such as bioprocessing, agriculture, biosensor, biopharmaceuticals and
medicine (Lateef et al. 2018; Elegbede and Lateef 2019a, b; Sekoai et al. 2019). More
specifically, nanotechnology has been employed in various bioprocesses to improve
the microbial metabolic activities by their integration with metabolic intermediates
and key enzyme activities. Consequently, increased glycolytic rates, cell-substrate
affinity, growth rate, mass transfer rate, modulation of oxidation–reduction potential (ORP) enhanced process performance and ultimately high product yields. This
chapter focuses on the recent progress made in the application of nanotechnology
for the enhancement of biofuel production processes. Furthermore, the impacts
of nanoparticles as biocatalytic additives in biodiesel, bioethanol, biohydrogen,
biomethane and biogas production are reviewed. Finally, the current challenges and
future outlook on the application of nanotechnology in biofuel production processes
are highlighted.
2 The Use of Nanotechnology in Biofuel Production
In the recent years, nanoparticles have attracted significant attention due to its distinctive physical and chemical nature that has shown to stimulate microbial and enzymatic biochemical activities in biofuel production. Previous studies have indicated
that the stimulatory and catalytic properties of nanoparticles are majorly influenced
by their shape, size, concentration, surface coating and operating conditions (Resham
and Priyabrata 2008). The use of biocompatible and bioactive nanomeric additives
such as NiO, Fe 3 O 4 and AgO nanoparticles in biofuel production processes that could
significantly improve bioprocess performance and productivity is being implemented
(Abdelsalam et al. 2016). Nanoparticle surface properties can regulate stability, solubility and targeting of specific cellular receptors (Howarth et al. 2008). Moreover,
the suitability of nanoparticle additives is strongly dependent on other factors such
as operating parameters, the type of substrate and additive type (Abdelsalam et al.
2016). For instance, monovalent and functionalized nanomaterial might be used to
stimulate or regulate the activities of individual proteins or enzymes (Fu et al. 2004;
Howarth et al. 2008). More specifically, for biological applications, the surface property is generally polar, which gives high aqueous solubility that prevents nanoparticles
aggregation and ultimately, their performance (Prime and Whitesides 1991; Liu et al.
2010).
Nanomaterials can also play a vital role to improve the thermal and pH stability
of enzymes (Pandurangan and Kim 2015). Furthermore, a coated nanoparticle
that is multivalent or polymeric confers high stability. Multivalent nanoparticles,
bearing multiple targeting groups, can cluster receptors, which could activate cellular