Test Catageory
فئة التحليل
Microbiology
Refrence Books
كتب مراجع
1. Bailey & Scott’s Diagnostic Microbiology
2. Laboratory Manual and Workbook in Microbiology
Skills Required
المهارات المطلوبة
1. Broth inoculation
2. Reagent addition and shaking
3. Color interpretation
Video Resources
مصادر فيديو
Principle
Glucose phosphate broth promotes acetyl-methyl-carbinol (acetoin) production from pyruvic acid during glucose breakdown. Diacetyl formed from acetoin causes a red color with added VP reagents.
Solutions & Equipments
1. Glucose phosphate broth
2. Bacterial isolate
3. VP reagents (creatinine/NaOH)
4. Culture tubes, racks
Sample Type
Pure bacterial isolate suspensions from cultures grown in glucose phosphate broth.
Procedure
1. Inoculate glucose phosphate broth; incubate up to 48 hours
2. Add VP reagents down sides of two tubes
3. Shake tubes gently and let sit 1 hour
4. Observe for distinct red coloration
Results
No color change – negative
Red color – positive
Interpretation
Determine acetoin production capability
Use to identify Enterobacteriaceae based on VP pattern
Notes:
Test known VP positive/negative strains
Ensure optimal incubation periods
Properly layer added VP reagents
M. Sulieman
mohammad@mlsgaate.com
Test known VP positive/negative strains
Ensure optimal incubation periods
Properly layer added VP reagents