Applications of Microbe-Based Nanoparticles …
363
mycogenic SeNPs synthesized from T. atroviride showed exceptional in vitro antifungal property against Pyricularia grisea and further inhibited the infection of
Colletotrichum capsici and Alternaria solani on chili and tomato leaves, respectively.
Nanofibrous mats were prepared using fungal chitosan and Trichoderma viride.
At 28 °C, T. viride multiplies rapidly and competes for space and nutrients against
phytopathogens such as Fusarium sp. and Alternaria sp. (Spasova et al. 2011). Penicillium duclauxii-mediated AgNPs (concentration ranging from 50 to 200 ppm) were
used to test antifungal activity against Bipolaris sorghicola. Results showed that
maximum percentage of inhibition was found to be 70% at 200 ppm AgNPs concentration (Almaary et al. 2020). Ibrahim et al. (2020) biosynthesized AgNPs from
endophytic bacterium Pseudomonas poae strain CO, isolated from Allium sativum
which inhibited the mycelium growth, spore germination, the length of the germ
tubes and the mycotoxin production of the wheat Fusarium head blight pathogen
Fusarium graminearum. Biosynthesized AgNPs from endophytic bacterium Bacillus
siamensis strain C1 inhibited Xanthomonas oryzae pv. oryzae (Xoo) strain LND0005,
a rice bacterial leaf blight and Acidovorax oryzae (Ao) strain RS-1, bacterial brown
stripe pathogen effectively and promoted the plant growth (Ibrahim et al. 2019). In
another study, different concentrations of AgNPs (2, 4 and 10 μg/ml) synthesized
using Serratia sp. BHU-S4 completely inhibited germination of conidia in Bipolaris
sorokiniana and encouraged plant growth in pathogen challenged plant (Mishra et al.
2014a).
Antibacterial activity of different concentrations of AgNPs (0.1–0.3 mM) obtained
from Spirulina platensis was effective against various plant pathogens such as Pseudomonas solanocearum, P. syringae, Xanthomonas malvacearum and X. campestris.
Further, it was also reported that addition of 1 μg of ciprofloxacin in conjunction
with 0.2 mM AgNPs enhanced the antibacterial activity against the tested bacterial
pathogens (Mala et al. 2012). Silver nanoparticles synthesized from Pseudomonas
rhodesiae have also been reported to inhibit Dickeya dadantii, a soft rot pathogen
at 50 μg/mL AgNPs concentration (Hossain et al. 2019). It is clearly evident that
nanoparticles that were produced by microbes could be exploited for nanocontrol
of plant pathogens to forestall disease outbreak, spoilage and loss of agricultural
produce.
3.2 Microbial Nano-biosensor
Wang et al. (2010) synthesized SeNPs using Bacillus subtilis. The results indicated
that bacterial proteins served as templates and eventually converted selenium from
monoclinic nano-sphere to trigonal nanowires. The biosensor thus developed had
high sensitivity and affinity for H 2 O 2 , and the detection limit for H 2 O 2 was found
to be 8 × 10
−8 M. Similarly, studies on Bacillus pumilus sp. BAB-3706 resulted
in the synthesis of SeNPs biosensor. The detection limit was found to be 3.00 μM
(Prasad et al. 2015). In another study, yeast cells were used to synthesize Au-Ag
alloy nanoparticles-based electrochemical sensor, which was highly sensitive toward
363
mycogenic SeNPs synthesized from T. atroviride showed exceptional in vitro antifungal property against Pyricularia grisea and further inhibited the infection of
Colletotrichum capsici and Alternaria solani on chili and tomato leaves, respectively.
Nanofibrous mats were prepared using fungal chitosan and Trichoderma viride.
At 28 °C, T. viride multiplies rapidly and competes for space and nutrients against
phytopathogens such as Fusarium sp. and Alternaria sp. (Spasova et al. 2011). Penicillium duclauxii-mediated AgNPs (concentration ranging from 50 to 200 ppm) were
used to test antifungal activity against Bipolaris sorghicola. Results showed that
maximum percentage of inhibition was found to be 70% at 200 ppm AgNPs concentration (Almaary et al. 2020). Ibrahim et al. (2020) biosynthesized AgNPs from
endophytic bacterium Pseudomonas poae strain CO, isolated from Allium sativum
which inhibited the mycelium growth, spore germination, the length of the germ
tubes and the mycotoxin production of the wheat Fusarium head blight pathogen
Fusarium graminearum. Biosynthesized AgNPs from endophytic bacterium Bacillus
siamensis strain C1 inhibited Xanthomonas oryzae pv. oryzae (Xoo) strain LND0005,
a rice bacterial leaf blight and Acidovorax oryzae (Ao) strain RS-1, bacterial brown
stripe pathogen effectively and promoted the plant growth (Ibrahim et al. 2019). In
another study, different concentrations of AgNPs (2, 4 and 10 μg/ml) synthesized
using Serratia sp. BHU-S4 completely inhibited germination of conidia in Bipolaris
sorokiniana and encouraged plant growth in pathogen challenged plant (Mishra et al.
2014a).
Antibacterial activity of different concentrations of AgNPs (0.1–0.3 mM) obtained
from Spirulina platensis was effective against various plant pathogens such as Pseudomonas solanocearum, P. syringae, Xanthomonas malvacearum and X. campestris.
Further, it was also reported that addition of 1 μg of ciprofloxacin in conjunction
with 0.2 mM AgNPs enhanced the antibacterial activity against the tested bacterial
pathogens (Mala et al. 2012). Silver nanoparticles synthesized from Pseudomonas
rhodesiae have also been reported to inhibit Dickeya dadantii, a soft rot pathogen
at 50 μg/mL AgNPs concentration (Hossain et al. 2019). It is clearly evident that
nanoparticles that were produced by microbes could be exploited for nanocontrol
of plant pathogens to forestall disease outbreak, spoilage and loss of agricultural
produce.
3.2 Microbial Nano-biosensor
Wang et al. (2010) synthesized SeNPs using Bacillus subtilis. The results indicated
that bacterial proteins served as templates and eventually converted selenium from
monoclinic nano-sphere to trigonal nanowires. The biosensor thus developed had
high sensitivity and affinity for H 2 O 2 , and the detection limit for H 2 O 2 was found
to be 8 × 10
−8 M. Similarly, studies on Bacillus pumilus sp. BAB-3706 resulted
in the synthesis of SeNPs biosensor. The detection limit was found to be 3.00 μM
(Prasad et al. 2015). In another study, yeast cells were used to synthesize Au-Ag
alloy nanoparticles-based electrochemical sensor, which was highly sensitive toward