Smell generating devices using growth
phases of Eau d’coli-
Results and discussion-
Designed banana smell generating devices were genetically inserted into Escherichia Coli cells, these
modified cells are referred to as Eau d’coli. In Table.1, bacterial cell density measured using OD600
(optical density at wavelength 600 nm) setting in the spectrophotometer for four different strains is shown.
The data is presented with measurements made every 20 to 40-minute intervals, 20 minutes was the
approximate time required for the bacteria to double in the population size. In between measurements,
the bacteria were placed in incubator shakers to grow in closed test tubes. In addition to the OD600
values, a score on the banana smell strength was estimated by comparing the smell of the bacterial
sample solution with a set of six different standard solutions ranging between 0 to 5% concentrations of
isoamyl acetate in water. The exact concentrations of the standard solutions are shown in the appendix.
Table.1 Four different strains of bacteria with their OD600 values and banana smell score-
Original device Score on banana smell
OD600* Number of cells Phase
(positive control) scale
T= 0 0.006 6000000 0 LAG
T= 20 0.006 6000000 1 LAG
T= 60 0.004 4000000 3 LAG
T= 80 0.039 39000000 3 LOG
T= 100 0.059 59000000 4 LOG
T= 120 0.411 411000000 5 LOG
T= 140 0.439 439000000 5 STATIONARY
T= 160 0.46 460000000 6 STATIONARY
Device with
Score on banana smell
inverter OD600 Number of cells Phase
scale
(design 1)
T= 0 0.021 21000000 4 LAG
T= 20 0.021 21000000 6 LAG
T= 60 0.035 35000000 6 LAG
T= 80 0.279 279000000 4 LOG
T= 100 0.449 449000000 3 LOG
phases of Eau d’coli-
Results and discussion-
Designed banana smell generating devices were genetically inserted into Escherichia Coli cells, these
modified cells are referred to as Eau d’coli. In Table.1, bacterial cell density measured using OD600
(optical density at wavelength 600 nm) setting in the spectrophotometer for four different strains is shown.
The data is presented with measurements made every 20 to 40-minute intervals, 20 minutes was the
approximate time required for the bacteria to double in the population size. In between measurements,
the bacteria were placed in incubator shakers to grow in closed test tubes. In addition to the OD600
values, a score on the banana smell strength was estimated by comparing the smell of the bacterial
sample solution with a set of six different standard solutions ranging between 0 to 5% concentrations of
isoamyl acetate in water. The exact concentrations of the standard solutions are shown in the appendix.
Table.1 Four different strains of bacteria with their OD600 values and banana smell score-
Original device Score on banana smell
OD600* Number of cells Phase
(positive control) scale
T= 0 0.006 6000000 0 LAG
T= 20 0.006 6000000 1 LAG
T= 60 0.004 4000000 3 LAG
T= 80 0.039 39000000 3 LOG
T= 100 0.059 59000000 4 LOG
T= 120 0.411 411000000 5 LOG
T= 140 0.439 439000000 5 STATIONARY
T= 160 0.46 460000000 6 STATIONARY
Device with
Score on banana smell
inverter OD600 Number of cells Phase
scale
(design 1)
T= 0 0.021 21000000 4 LAG
T= 20 0.021 21000000 6 LAG
T= 60 0.035 35000000 6 LAG
T= 80 0.279 279000000 4 LOG
T= 100 0.449 449000000 3 LOG
