ratio of α-chymotrypsin slightly decreased from 7.6 Æ 0.2 to 6.0 Æ 0.1 Â 10
5 1/(M s)
comparing the native and the coated enzymes, the stability of the coated enzymes
increased drastically retaining ca 90% of its initial activity after 3 days of the use,
whereas the activity of native enzymes at that point was only about 10%. A similar
strong stabilization effect was observed for lipase (Hong et al. 2017).
In addition to artificial nanoparticles, Ng et al. (2015) investigated the production
of natural nanoparticles with multiple enzymatic activities by algae Shewanella
(Ng et al. 2015). Shewanella xiamenensis BC01 produced nanoparticles with oxidoreductases including catalase, manganese peroxidase, laccase, NADH dehydrogenase, flavin reductase, azoreductase, and Fe reductase that were generally
spherical in shape with a particle size of 7–8 nm (Ng et al. 2015).
Engineered enzymes as well as their producers are a rapidly expanding field of
research allowing for production of large quantities of more stable, active, and/or
selective enzymes, yielding cheaper products with a higher utility value (Zhang et al.
2016b).
24.3.4 Enzymes in Prevention and Detection
of Contamination
Enzymes, e.g., chitinases, proteases, and lipases, can be used as eco-friendly
biopesticides because of their anti-insect and anti-fungal potential. Chitinases–bacterial, fungal, or plant–are promising agents for controlling harmful fungi and plants
owing to the presence of chitin in the exoskeletal and intestinal linings of insects and
in the fungal cell walls (Yan et al. 2008; Liu et al. 2002). Binod et al. (2007) reported
that chitinase of Trichoderma harzianum negatively affects the growth and the
metamorphosis of Helicoverpa armigera larvae, with up to 70% mortality rate.
Proteases cleaving the peptide bonds of proteins are naturally produced by insect
and nematode pathogens in order to penetrate cuticles made up of 70% of protein
(Goettel et al. 1989). Serine proteases isolated from a nematophagous fungus,
Lecanicillium psalliotae, were able to eradicate nematode Panagrellus redivivus
with 81–100% efficiency (Yang et al. 2005).
On a similar token, lipases may be used for insect control by hydrolyzing ester
bonds of lipoproteins, fats, and waxes in the interior parts of the insect body. A purified
extracellular lipase from a fungus applied for biocontrol, Nomuraea rileyi MJ, was
used, as a single agent, to both promote the fungus spore germination and enhance the
mortality of an agricultural pest, Spodoptera litura (Supakdamrongkul et al. 2010).
Currently, synergistic effects of enzymes and toxin-derived biopesticides, e.g.,
δ-endotoxins of Bacillus thuringiensis, are investigated when these agents are applied
in combination. Protease and chitinase of Paecilomyces lilacinus were studied by
512
M. Halecký and E. Kozliak
5 1/(M s)
comparing the native and the coated enzymes, the stability of the coated enzymes
increased drastically retaining ca 90% of its initial activity after 3 days of the use,
whereas the activity of native enzymes at that point was only about 10%. A similar
strong stabilization effect was observed for lipase (Hong et al. 2017).
In addition to artificial nanoparticles, Ng et al. (2015) investigated the production
of natural nanoparticles with multiple enzymatic activities by algae Shewanella
(Ng et al. 2015). Shewanella xiamenensis BC01 produced nanoparticles with oxidoreductases including catalase, manganese peroxidase, laccase, NADH dehydrogenase, flavin reductase, azoreductase, and Fe reductase that were generally
spherical in shape with a particle size of 7–8 nm (Ng et al. 2015).
Engineered enzymes as well as their producers are a rapidly expanding field of
research allowing for production of large quantities of more stable, active, and/or
selective enzymes, yielding cheaper products with a higher utility value (Zhang et al.
2016b).
24.3.4 Enzymes in Prevention and Detection
of Contamination
Enzymes, e.g., chitinases, proteases, and lipases, can be used as eco-friendly
biopesticides because of their anti-insect and anti-fungal potential. Chitinases–bacterial, fungal, or plant–are promising agents for controlling harmful fungi and plants
owing to the presence of chitin in the exoskeletal and intestinal linings of insects and
in the fungal cell walls (Yan et al. 2008; Liu et al. 2002). Binod et al. (2007) reported
that chitinase of Trichoderma harzianum negatively affects the growth and the
metamorphosis of Helicoverpa armigera larvae, with up to 70% mortality rate.
Proteases cleaving the peptide bonds of proteins are naturally produced by insect
and nematode pathogens in order to penetrate cuticles made up of 70% of protein
(Goettel et al. 1989). Serine proteases isolated from a nematophagous fungus,
Lecanicillium psalliotae, were able to eradicate nematode Panagrellus redivivus
with 81–100% efficiency (Yang et al. 2005).
On a similar token, lipases may be used for insect control by hydrolyzing ester
bonds of lipoproteins, fats, and waxes in the interior parts of the insect body. A purified
extracellular lipase from a fungus applied for biocontrol, Nomuraea rileyi MJ, was
used, as a single agent, to both promote the fungus spore germination and enhance the
mortality of an agricultural pest, Spodoptera litura (Supakdamrongkul et al. 2010).
Currently, synergistic effects of enzymes and toxin-derived biopesticides, e.g.,
δ-endotoxins of Bacillus thuringiensis, are investigated when these agents are applied
in combination. Protease and chitinase of Paecilomyces lilacinus were studied by
512
M. Halecký and E. Kozliak