module 5b biochemical activities for the lab
DESCRIPTION
dr lu5bTRANSCRIPT
BIOCHEMICAL ACTIVITIES
Principle, Reagents & MediaProcedures & 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