HALOGENATED SPECIES - Oxidation of Amino Acids, Peptides, and Proteins: Kinetics and Mechanism - page 100

TABLE 3.6. Log Reductions Obtained by a Treatment with 0.08 ± 0.02 mg ClO 2 /L
for 1 Minute at RH 90 ± 0.5% and Room Temperature

log Reduction a (log cfu) Microorganism

Bacteria, gram-negative
Aeromonas hydrophila

2.6 ± 0.9

Enterobacter aeruginosa 3.4 ± 0.8

Escherichia coli 2.7 ± 0.6

Klebsiella oxytoca 3.1 ± 0.7

Pseudomonas fluorescens 0.5 ± 0.5

Salmonella typhimurium 3.2 ± 0.3

Shigella flexnii 3.4 ± 0.5

Yersinia entercolitica 3.5 ± 0.6

Bacteria, gram-positive
Brochotrix thermosphacta 1.4 ± 0.7

Lactobacillus sakei 2.6 ± 0.6

Leuconostoc mesenteroïdes 3.2 ± 0.4

Listeria monocytogenes 2.8 ± 0.6

Staphylococcus aureus 3.1 ± 0.5

yeasts
Candida lambica 1.1 ± 0.2

Pichia burtonii 2.0 ± 0.5

Saccharomyces cerevisiae 0.6 ± 0.1

Mold spores
Aspergillus niger 0.1 ± 0.1

Penicillium roqueforti 0.4 ± 0.5

Botrytis cinerea 0.9 ± 0.4

Bacterial spores
Bacillus cereus 0.2 ± 0.2

a Mean ± standard deviation, n = 6.
Adapted from Vandekinderen et al. [133] with the permission of Elsevier Inc.

were 3.5 and 2.6 log cfu/cm 2 (Table 3.6). yeasts were more resistant to ClO 2
than gram-negative bacteria and gram-positive bacteria. Significantly, ClO 2 has
been shown to be effective in deactivating Bacillus anthracis spores in govern-
mental and commercial buildings [134-137]; however, Bacillus cereus was little
affected by ClO 2 (Table 3.6).
The bactericidal capacity of ClO 2 was shown to be higher than that of liquid
chlorine [138]. The bactericidal rate of ClO 2 was found to be faster than that
of liquid chlorine. Significantly, Bacillus could be killed by ClO 2 in the pH range
from 3.0 to 8.0. However, the pH range in using liquid chlorine to achieve a
similar effect for killing was much narrower (6.8-8.5). Values of Ct are used to
express the level of disinfection, which is the concentration of disinfectant (in
milligram per liter) multiplied by the contact time (in minutes). Ct values for