Question

CTED VIEW Be careful files from the Internet can contain viruses. Unless you need to edit, it's safer to stay in Pra Metabolic Tests Workshe Summary Complete the following table that summarizes the tests that we conducte Appearance of Result What causes Reaction/Enzyme Used/Innoculation N the change in the Result medium's Test Biochemical Medium Involved Procedure Result appearance? Lactose Fermentation Gelatinase Starch Hydrolysis Urease Citrate Permease CatalaseARREN Tryptophanase Casein SIM Nitrate Reduction Questions Answer the following questions about the metabolic tests we performed in cla 1. You inoculate an organism into phenol red sucrose broth. The organism f sucrose. a. Whai color is the medium? b. What does this tell you about the pH of the medium? c. The organism ferments sucrose and produces gases. What do you us detect gas production? d. What do you see that indicates that gases are produced?

Answer 1

Ans.1)

(a) The media is red coloured clear solution without any precipitate.

(b) The media is alkaline in pH, with pH value of 7.5. This media turns yellow in presence of acid due to fermentation of sucrose.

(c) Gas produced by microbes is seen in Durhams tubes. Durhams tubes are inverted tubes placed in another test tube containing media.

(d) When the durhams tubes are placed inside the media tube, it is completely filled with media but as gas formation starts the media is get replaced by gas in inverted durhams tubes. The level of tubes emptied can be noticed easily.

Theory: Phenol Red Sucrose Broth is used for sucrose fermentation studies of microorganisms. Phenol Red Broth Medium with various carbohydrates serves as a differential medium by aiding in differentiation of various species and genera by their ability to ferment the specific carbohydrate, with the production of acid or acid and gas.