Table 2 The mean bactericidal effect (log reduction) of PAA and H2O2 against  A. hydrophila.

From: In-vitro and in-vivo assessment of the bactericidal potential of peracetic acid and hydrogen peroxide disinfectants against A. hydrophila infection in Nile tilapia and their effect on water quality indices and fish stress biomarkers

  

Vc1

Vc2

N AND N0

 

Test-suspension (N and No):

107

118

124

N = 147.272 × 107, lg.N = 9.16N0 = N/10 = lg N0 = 8.16

 

108

40

42

  

EGY-VIROX 5% (PAA 1 mg / l)

Contact Time

VC1

VC2

NA

Na = 10c/n

lgNa

Lg R (M.E)

(No = 8.16)

1 min

>300

>300

1380

3.47

4.69

5 min

>300

>300

1380

3.47

4.69

30 min

170

<30

1000

3

5.16

AQUAPLUS 50% (H2O2 20 mg/l)

1 min

>300

> 300

1380

3.47

4.69

5 min

200

< 30

1150

3.06

5.1

30 min

130

< 30

1000

2.9

5.26

  1. N: Number of colony-forming units (CFUs) per ml of bacteria in the suspension used in the test. = C/ (n1 + 0.1n2)10−7, where: C is the sum of Vc values considered.
  2. n1 is the number of Vc values considered in the lower dilution, i.e. 10−7.
  3. n2 is the number of Vc values considered in the higher dilution, i.e. 10−8.
  4. N0: Number of CFUs per ml in the test mix., N0 = N/10.
  5. Na: The count of the survived bacteria after the treatment of disinfectant = 10c/n.
  6. c is the sum of Vc values considered; and n is the number of Vc values taken into account.
  7. The log reduction (R) = (LgN0 - lgNa) must be ≥ 5 to pass the test.
  8. VC: Number of viable CFU on plate.
Back to article page