Hi Ms Chew... i read up on some biochemical tests avaliable in my lab... so here they are:

The Indole Test

The organism is inoculated into tryptone broth. Indole positive bacteria such as Escherichia coli produce tryptophanase, an enzyme that cleaves tryptophan, producing indole and other products. When Kovac's reagent is added to a broth with indole in it, a dark pink color develops. The indole test must be read by 48 hours of incubation because the indole can be further degraded if prolonged incubation occurs. The acidic pH produced by Escherichia coli limits its growth.


The Citrate Test

The citrate test utilizes Simmon's citrate media to determine if a bacterium can grow utilizing citrate as its sole carbon and energy source. Simmon's media contains bromthymol blue, a pH indicator with a range of 6.0 to 7.6. Bromthymol blue is yellow at acidic pH's (around 6), and gradually changes to blue at more alkaline pH's (around 7.6). Uninoculated Simmon's citrate agar has a pH of 6.9, so it is an intermediate green color. Growth of bacteria in the media leads to development of a Prussian blue color (positive citrate). Enterobacter and Klebsiella are citrate positive while E.coli is negative.

Triple sugar Iron (TSI) - & Hydrogen sulfide production (H2S)

Examines fermentation of glucose, lactose, and sucrose and checks if hydrogen sulfide is produced in the process. A pH indicator will change the color of the media in response to fermentation. Where the color change occurs in the tube will indicate what sugar or sugars were fermented. The presence of a black color indicates that H2S was produced. To inoculate, use a needle to stab agar and then uses a loop to streak the top slated region.

SLANT COLOR:
Interpretation
RED
Does not ferment either lactose or sucrose
YELLOW
Ferments lactose and/or sucrose


BUTT COLOR/CONDITION:
Interpretation
RED
No fermentation of glucose
YELLOW
Some fermentation of glucose has occurred, acid has been produced
GAS FORMED
Seen as cracks in the agar, bubbles, or the entire slant may be pushed out of the tube.
BLACK
H2S has been produced

Motility test

This test can be used to check for the ability of bacteria to migrate away from a line of inoculation thanks to physical features like flagella. To perform this test, the bacterial sample is inoculated into motility media using a needle. Simply stab the media in as straight a line as possible and withdraw the needle very carefully to avoid destroying the straight line. After incubating the sample for 24-48 hours observations can be made. Check to see if the bacteria have migrated away from the original line of inoculation. If migration away from the line of inoculation is evident then you can conclude that the test organism is motile (positive test). Lack of migration away from the line of inoculation indicates a lack of motility (negative test result).

Oxidation - fermentation tests (OF test)

This biooxidation test is used to decide the oxidative or fermentative metabolism of a carbohydrate or its non-utilization.

A. OF Media (green colored)
Use for Gram-negative rods.
yellow = positive green or blue = negative

B. CTA Media (orange colored)
Use for Gram-positive cocci.
yellow = positive orange or red = negative

Nitrate test

This is a test used to detect the presence of nitrite. Some facultative bacteria convert nitrate to nitrite by removing an oxygen from nitrate using the enzyme nitratase.

Interpretation:
After incubation, the broth must be turbid. A clear broth indicates that your organism did not grow and cannot be tested. Add several drops of 2% acetic acid to the broth culture. Shake gently. A positive reaction is shown by production of a dark color.