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Table 1 Kinetics of E. coli O157:H7 and Salmonella survival in free-floating and particle-attached conditions in stream water (time is in minute)

From: Particle attached and free floating pathogens survival kinetics under typical stream and thermal spring temperature conditions

Temp. (°C) E. coli O157:H7 Salmonella
Free-floating Particle attached Free-floating Particle attached
  Equations of decay curves2
30 ay  = − 0.00066 × (time) + C0 ay = − 0.00065 × (time) + C0 ay = − 0.00055 × (time) + C0 ay = − 0.00062 × (time) + C0
40 by = − 0.00062 × (time) + C0 by = − 0.00044 × (time) + C0 by = − 0.00052 × (time) + C0 by = − 0.00072 × (time) + C0
50 cy = − 0.01448 × (time) + C0 dy = − 0.00308 × (time) + C0 ey = − 0.02000 × (time) + C0 fy = − 0.00454 × (time) + C0
60 gy = − 0.09910 × (time) + C0 hy = − 0.08188 × (time) + C0 iy = − 0.10908 × (time) + C0 jy = − 0.04308 × (time) +  C0
  First order rate constant [k]3 (min−1)
a30 0.00152 0.00150 0.00128 0.00143
b40 0.00143 0.00092 0.00120 0.00165
c50 0.03334 0.00709 0.04606 0.01044
d60 0.22822 0.18857 0.25120 0.09920
  Z-value4
  9.14746 8.65426 8.30772 11.32888
  1. Different letters in subscript of regression equations shows the line is significantly different at p < 0.05
  2. Similar letters in subscript of z-values show the values are not significantly different at p < 0.05
  3. Different letters in subscript of k-values show that these values were significantly different among temperature at p < 0.05
  4. 1C0 = initial pathogen concentration (CFU/mL)
  5. 2R2 values for decay curve varied between 0.75 and 0.99
  6. 3Rate constant (k) was estimated from D-values (k = 2.303/D)
  7. 4The Z-values were estimated based on slope (i.e., z-value = − 1/(slope between temperature and D-value)