100 likes | 415 Views
The Effect of Caffeine on Growth of Pseudomonas fluorescens. Author: Eric Huffman Samy Behairy . In the Mix. P. fluorescens, a common bacteria found in soil and water, that also has a versatile metabolism. 2% nutrient broth is used for optimum growth in solution.
E N D
The Effect of Caffeine on Growth of Pseudomonas fluorescens Author: Eric Huffman SamyBehairy
In the Mix • P. fluorescens, a common bacteria found in soil and water, that also has a versatile metabolism. • 2% nutrient broth is used for optimum growth in solution. • Caffeine a stimulant to humans, is used as a defense mechanism against insects and fungi.
Hypothesis • Given the research on caffeine production by plants and from scholarly articles, it is hypothesized that caffeine will act as a antibacterial agent on the growth of P. fluorescens. • Given high mutation rates of bacteria, in 2% Nutrient broth, it is hypothesized that P. fluorescens can mutate toresist increasing levels of caffeine concentrations.
What and How? • What is the concentration of NB to support optimal growth of P. fluorescens? • What is the effect of caffeine in various concentrations on the growth of the bacteria with optimal NB concentration? • How resistant can we make overnight cultures of P.fluorescensto those caffeine concentrations in the shortest amount of time?
Conclusion • Both hypothesis were proven, with limitations. • Caffeine had an antibacterial effect on P. fluorescens, decreasing growth as caffeine percentage increased. • Inoculated to increasing percentages of caffeine in overnight cultures, P. fluorescens showed increased resistance with negative feedback at levels inoculated above 1% caffeine overnight cultures. • Future research can study the effects of higher concentration of caffeine where sample size is not a limitation (difficulty maintaining proportions) • Why do resistant cultures take longer for the initial growth burst (Lag Phase)?
Sources • Pictures in order. • http://web.mst.edu/~microbio/BIO221_2009/images_2009/Pseudomonas-1.jpg • http://www.caffeine.com/2762115755_162d5e3423_o.png • http://7bigspoons.com/wp-content/uploads/2011/06/bacteria-living-on-caffeine-only.png