Application of Microbial-Synthesized Nanoparticles …
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UV light) (Vilela et al. 2018; Yildirim et al. 2018), but some active food packaging
systems are developed to act in both forms (Table 1). The following sections comprise
the main applications of nanoparticles in AP systems.
3.2.2 Active Emitters
The antimicrobial properties of AP materials are widely studied due to the negative impacts of uncontrolled microbial growth in food. Antimicrobial packaging
systems are generally used in meat, seafood, fresh and processed vegetables and
fruits, cereals, grains, bakery, and dairy products to inhibit cell growth and extend
shelf life (Yildirim et al. 2018). In antimicrobial AP system, antimicrobial agents,
such as essential oils, plant extracts, organic acids, metals, enzymes, biopolymers,
bacteriocins (antimicrobial proteins), proteins, and other antimicrobial agents, are
added into the package system (Khaneghah et al. 2018b). Likewise, antioxidants
emitters packaging systems are used for improving the oxidative stability of meat,
seafood, nuts, high-oil-content food, and oils, while CO 2 emitters prevent microbial
growth and extend shelf life of meat (Yildirim et al. 2018).
Natural compounds can be associated with metal-based nanoparticles either for
their biosynthesis or as a matrix, improving their antimicrobial and antioxidant activities. Essential oils are extracted from aromatic plants and present several medicinal
properties. These compounds are widely explored in the food industry due to antimicrobial properties; in addition, terpenoids, phenols, and aldehydes are their main
components and their hydrophobicity contributes to the damage of microbial cells
(Khaneghah et al. 2018a). Mohammadi et al. (2020) produced an AP film based on
whey protein isolate associated with cinnamon essential oil and chitosan nanofiber.
In this study, cinnamon oil (a natural antimicrobial and antioxidant) and chitosan
nanofiber were both structured as lipid nanocarriers, and the use of chitosan nanofiber
improved the film mechanical properties, while cinnamon oil increased antibacterial activity against the common food pathogens Escherichia coli, Staphylococcus
aureus, and Pseudomonas aeruginosa.
Biopolymers and amino acids are among the most studied compounds in AP
systems due to their antimicrobial properties. Ibrahim et al. (2019) evaluated the use
of lysine amino acid conjugated with a nano-biodegradable polymer (polystyrene
sulfate) as an edible coat in paper sheets and observed an enhancement of the
antimicrobial activity against several bacteria and yeast pathogens, as well as the
improvement of its mechanical and physical properties. Pandey et al. (2020) studied
chitosan, a natural polymer, in the form of nano-layers in AP systems for meat packaging and demonstrated an effective antimicrobial activity against Listeria monocytogenes and Escherichia coli bacteria. In another study, Liu et al. (2020) produced
nanocomposite films using a soybean soluble polysaccharide, zinc nanoparticles, and
micro-fibrillated cellulose, exhibiting an efficient antibacterial activity.
Among nanomaterials, AgNPs are widely studied for their antimicrobial properties, and their production using plant extracts is an alternative green method of
411
UV light) (Vilela et al. 2018; Yildirim et al. 2018), but some active food packaging
systems are developed to act in both forms (Table 1). The following sections comprise
the main applications of nanoparticles in AP systems.
3.2.2 Active Emitters
The antimicrobial properties of AP materials are widely studied due to the negative impacts of uncontrolled microbial growth in food. Antimicrobial packaging
systems are generally used in meat, seafood, fresh and processed vegetables and
fruits, cereals, grains, bakery, and dairy products to inhibit cell growth and extend
shelf life (Yildirim et al. 2018). In antimicrobial AP system, antimicrobial agents,
such as essential oils, plant extracts, organic acids, metals, enzymes, biopolymers,
bacteriocins (antimicrobial proteins), proteins, and other antimicrobial agents, are
added into the package system (Khaneghah et al. 2018b). Likewise, antioxidants
emitters packaging systems are used for improving the oxidative stability of meat,
seafood, nuts, high-oil-content food, and oils, while CO 2 emitters prevent microbial
growth and extend shelf life of meat (Yildirim et al. 2018).
Natural compounds can be associated with metal-based nanoparticles either for
their biosynthesis or as a matrix, improving their antimicrobial and antioxidant activities. Essential oils are extracted from aromatic plants and present several medicinal
properties. These compounds are widely explored in the food industry due to antimicrobial properties; in addition, terpenoids, phenols, and aldehydes are their main
components and their hydrophobicity contributes to the damage of microbial cells
(Khaneghah et al. 2018a). Mohammadi et al. (2020) produced an AP film based on
whey protein isolate associated with cinnamon essential oil and chitosan nanofiber.
In this study, cinnamon oil (a natural antimicrobial and antioxidant) and chitosan
nanofiber were both structured as lipid nanocarriers, and the use of chitosan nanofiber
improved the film mechanical properties, while cinnamon oil increased antibacterial activity against the common food pathogens Escherichia coli, Staphylococcus
aureus, and Pseudomonas aeruginosa.
Biopolymers and amino acids are among the most studied compounds in AP
systems due to their antimicrobial properties. Ibrahim et al. (2019) evaluated the use
of lysine amino acid conjugated with a nano-biodegradable polymer (polystyrene
sulfate) as an edible coat in paper sheets and observed an enhancement of the
antimicrobial activity against several bacteria and yeast pathogens, as well as the
improvement of its mechanical and physical properties. Pandey et al. (2020) studied
chitosan, a natural polymer, in the form of nano-layers in AP systems for meat packaging and demonstrated an effective antimicrobial activity against Listeria monocytogenes and Escherichia coli bacteria. In another study, Liu et al. (2020) produced
nanocomposite films using a soybean soluble polysaccharide, zinc nanoparticles, and
micro-fibrillated cellulose, exhibiting an efficient antibacterial activity.
Among nanomaterials, AgNPs are widely studied for their antimicrobial properties, and their production using plant extracts is an alternative green method of