Frontiers in Marine Science,
Год журнала:
2023,
Номер
10
Опубликована: Май 12, 2023
Ultraviolet
disinfection
is
an
important
method
for
controlling
the
large-scale
outbreaks
of
diseases
in
aquaculture.
As
a
novel
and
promising
light
source,
ultraviolet
light-emitting
diode
(UV-LED)
has
advantages
safety,
high
efficiency
no
environmental
pollution
risks.
However,
it
remains
unclear
whether
UV-LEDs
can
replace
traditional
UV
sources
aquaculture
water
treatment
processes.
Present
study
aimed
to
investigate
efficacy
UVC-LEDs
(265
nm)
on
pathogenic
bacteria,
specifically
Aeromonas
salmonicida
Escherichia
coli
.
The
effects
UVC-LED
dose,
conditions,
temperature
bacterial
reactivation
were
also
investigated.
results
showed
that
exposure
effectively
inactivated
both
types
bacteria.
To
achieve
4.5-log
inactivation
A.
E.
,
24
mJ/cm
2
28
irradiation
required,
rate
increased
with
increasing
fluence.
Both
revived
after
disinfection,
photoreactivation
was
significantly
higher
than
dark
reactivation.
Bacterial
due
high-dose
lower
low-dose.
After
72
h
reactivation,
rates
1
±
0.4%
2.2
0.2%for
0.02%
0%
respectively.
Besides,
two
bacteria
exhibited
different
correlations
temperature.
highest
68.7
4%
at
20°C,
while
53.98
2.9%
15°C
48
h.
This
reveals
rapid
efficient
by
UVC-LED,
elucidates
mechanism
influencing
factors
UVC-LED.
highlights
adequate
avoidance
visible
inhibit
Our
findings
form
reference
design
operation
Water,
Год журнала:
2024,
Номер
16(11), С. 1625 - 1625
Опубликована: Июнь 6, 2024
A
novel
heterotrophic
aerobic
denitrifying
Pseudomonas
hunanensis
strain
DC-2
was
screened
from
the
sediments
of
Lake
Dianchi
and
identified
with
high
nitrification/denitrification
ability.
Within
30
h,
removal
efficiency
ammonium-N
nitrate-N
could
reach
98.8%
88.4%,
respectively.
The
results
single-factor
experiments
indicated
that
exhibited
excellent
denitrification
ability
under
conditions
using
sodium
citrate
as
nitrogen
source,
an
initial
pH
7,
a
C/N
ratio
10,
temperature
°C.
Nitrogen
balance
suggested
this
removed
N
mainly
via
assimilation.
Moreover,
pathway
explored
by
genome
enzymatic
assays,
complex
metabolism
established,
including
nitrification-aerobic
(HN-AD),
assimilatory
reduction
nitrate
(ANRA),
ammonia
Additionally,
immobilized
into
particles
for
denitrification,
demonstrating
efficacy
in
continuous
total
(84.8%
TN).
Hence,
demonstrated
significant
potential
treating
real
aquaculture
wastewater.