Transcript of "Module 5b biochemical activities for the lab"
Principle, Reagents & MediaProcedures & End resultsBIOCHEMICAL ACTIVITIES
BIOCHEMICAL ACTIVITIES OF BACTERIA:Biochemical properties could be used as tools of identification demonstrate certain metabolic activity of microbesExample : 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 carbinolfrom glucose•media: MR-VP broth•reagent: 40% KOH•Positive (+) result = production ofan 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
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