Urease and Urea Agar

Serial Dilutions Exercise

Study: Women lead men in bacteria, hands down

Study: Women lead men in bacteria, hands down

The Oxidase Test - 10/30/08

Phenol Red Glucose - 10/30/08

Phenol red glucose: Uninoculated control tube vs. culture of E. coli (right).






















Phenol red glucose: Both of these organisms produce acid from glucose (how can you tell?) Also, the organism on the left is gas (+) *compare durham tubes!

IMViC - 10/30/08

Simmons' Citrate - 10/30/08 Lecture

Bromothymol blue is used as a pH indicator - starting color around pH 6.8 is green. So why does Simmons Citrate change its color from green to royal blue? This is because alongside citrate, which gets converted into pyruvic acid and some other end products, the medium contains ammonium salts that produce ammonia and ammonium hydroxide upon their utilization thus resulting in an increase in alkalinity and a color change in the pH color indicator.