1. Hyun Suk Park Anh Trinh Carissa Best
Would glucose or lactose be more beneficial for the growth of P. fluorescens?
Hyun Suk Park
Anh Trinh
Carissa Best
Glucose

2. The Critter Pseudomonas fluorescens Gram negative, rod-shaped
Thrives in environments of 25 degrees Celsius
Able to grow on a variety of media including lactose

3. Why we picked lactose?
To examine the effects on growth rate in comparison to glucose.
20% concentration of Glucose OD
Concluded that the glucose concentration was too high.
Toxified cells led to early death, thus we decided to lover glucose concentration.
Used this info to derive acceptable lactose concentration
Time(min)

4. Glucose vs. Lactose
P. Fluorescens growth on lactose or media enriched culture OD
-Glucose(3%)
-Lactose(3%)
0%-20% concentration of lactose and 0%-11% concentration of glucose. The lactose was able to slow and decrease the growth of the organism. However, most noteably in the stationary phase.
Although P. fluorescens did grow at a slower rate on lactose, it showed a more controlled growth than on lactose then glucose media.
Time(min)

5. Lactose concentrations
Further explore an effective amount of lactose at the lowest concentration possible to steady the growth rate OD
Due to contamination or human error at some point in the procedure for experiment 6 or 7 the data was unusable.
In experiment 8 there is an increasing trend on growth from the .01 µL-.07 µL, however we can not definitively say this because of the accuracy of the pipettes.
Time(min)

6. Conclusion
Lactose effectively controlled the overall growth of P. fluorescens in comparison to glucose within a certain range
At very low concentrations of lactose a more accurate transfer method is needed to have significant measures of the effects on overall growth

7. Next Time Possible further experiments with additional time
Better dilution method/procedure
Lactose solution settling and preparation