module 5b biochemical activities for the lab
TRANSCRIPT
BIOCHEMICAL ACTIVITIES
Principle, Reagents & Media
Procedures & End results
BIOCHEMICAL ACTIVITIES OF BACTERIA:
Biochemical properties could be used as tools
of identification demonstrate certain
metabolic activity of microbes
Example : Fermentation – durham tubes
Carbohydrates, amino acids, organic
acids 1. gases – Carbone dioxide, methane, hydrogen
2. Acid production – use of indicators to detect
Either acid or gas or both can be collected
IMVIC - INDOLE TEST
Principle : product of hydrolysis of an amino acid
tryptophan
Media – SIM (Sulfide Indole Motility)
Reagent - (Ehrlich’s) Para-dimethyl-
aminobenzaldehyde
Positive result :(+) pink or red color
Negative Result : (-) absence of pink or red color
IMVIC - METHYL RED TEST
Methyl red is a pH indicator
Principle : production of sufficient acidity from
glucose
Media- MR-VP broth
(+) red - acid
(-) yellow - alkaline
IMVIC - VOGUES PROSKAUER
• production of acetyl-methyl carbinol
from glucose
•media: MR-VP broth
•reagent: 40% KOH
•Positive (+) result = production of
an eosin like color
IMVIC - CITRATE UTILIZATION TEST
Principle: utilizes citrate as a source of Carbon
Media :Simmon Citrate (SCA)
(+) blue color
(--) green color
OTHER COMMON BIOCHEMICAL TESTS:
Coagulase test
Catalase test
Urease test
Hemolysis test
Greig’s Test
Oxidase Test
Hydrogen Sulfide Test
ASSIGNMENT:
Find the other biochemical Tests & tabulate
them based on:
Working principle
Reagents & Media
Positive & Negative Results
WHAT TO DO?
Place all your glassware in a plastic bag
Autoclave 15 psi, 121 C, 15 minutes
Wash , clean and dry
Wrap and sterilize in the oven, 150 C, 45
minutes
MEDIA PREPARATION
Prepare 200 ml each ( for the whole class)
SIM
MRVP
SCA
Dispense into 4 test tubes
1 tube SIM
2 tubes MRVP
1 tube SCA ( Slant )
Inoculate with bacteria ( get from me )
Incubate in incubator 48 hours
Add the reagents ( from previous slides )
Check results
Make a one page write – up
Submit