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Figures index
From
The Origin of the Time Scale: A Crucial Issue for Predictive Microbiology
Alberto Schiraldi
Journal of Applied & Environmental Microbiology
.
2022
, 10(1), 35-42 doi:10.12691/jaem-10-1-4
Figure 1.
Sketch of the ideal growth curve according to the proposed model. The latency gap of the present model substantially differs from the lag phase, λ, considered in preexisting models [7]
Full size figure and legend
Figure 2.
Gathered growth curves from a variety of microbes (Lactobacillus delbrueckii subsp. bulgaricus, Streptococcus thermophilus, Salmonellae, C. jejuni, Pseudomonas fluorescens and Candida sake) adjusted from [18]. For further data, see also Figure 2 in [21]
Full size figure and legend
Figure 3.
The origin of the time scale of the microbial culture, θ, differs from that of the experimenter, t. The dashed line that allows calculation of θ
0
corresponds to the level –β
/8. For 0 < θ < θ
0
, the microbial culture experiences activities related to the incoming duplication (active latency gap). Plate count data come from a batch culture of Pseudomonas aeruginosa at 5°C [26]. Calculated values: t
start
= -20 h; t
0
= 12 h; θ
0
= 32 h
Full size figure and legend
Figure 4.
Growth curves from different N
0
inoculums, at the same temperature, aligned along the same straight line that corresponds to the same maximum specific duplication rate, μ
Full size figure and legend
Figure 5.
The width of the active latency gap, θ
0
, vanishes for log
2
(N
0
) = log
2
(N
max
)/9. At a given T, θ
0
increases on increasing log
2
(N
0
), but decreases on increasing T. Its upper limit, log
2
(N
max
)/μ, decreases on increasing T
Full size figure and legend
Figure
6
.
The maximum specific duplication rate increases with increasing temperature, while no significant changes concern the maximum population density, N
max
. Such a behavior occurs for the batch cultures of psychrotrophic bacteria [21]
Full size figure and legend
Figure
7
.
The change of the temperature from T
1
to T
2
or T
3
(T
2
> T
1
> T
3
) modifies the growth trend. θ
change
, is the new origin of the time scale for the culture and the corresponding level of the cell population is the new log
2
(N
0
). (θ
0,2
– θ
change
) and (θ
0,3
– θ
cha
nge
) are the intermediate latency gaps for the T
1
→ T
2
and T
1
→ T
3
temperature changes
Full size figure and legend