BACTE LA 17 Flashcards
Are microorganisms whose presence in water indicates probable presence of pathogens
INDICATOR ORGANISMS
defined as rode shaped gram negative nonendospore forming bacteria that ferment lactose with production of acid and gas at 35-37 deg C
COLIFORM
Enterobacteriaceae species that are not included in the TOTAL COLIFORMS
SALMONELLA
SHIGELLA
TOTAL COLIFORMS species that are not included in the FECAL COLIFORMS
ENTEROBACTER
CITROBACTER
MULTIPLE TUBE FERMENTATION TECHNIQUE Presumptive test
LAURYL TRYPTOSE BROTH
MULTIPLE TUBE FERMENTATION TECHNIQUE Confimatory test
TOTAL COLIFORM- Brilliant Green Bile Lactose Broth
FECAL COLIFORM- E. coli Broth
E. coli count- E. coli- MUG broth
MULTIPLE TUBE FERMENTATION TECHNIQUE Completion test
EMB Agar and Gram Staining
LAURYL TRYPTOSE BROTH
- Nitrogen & Carbon Source
- Carb Source
- Noncoliforms Inhibitor
- Fecal Streptococci Inhibitor
- Maintains osmosis
- PEPTONE
- LACTOSE
- SODIUM LAURYL SULPHATE
- BILE SALTS
- SODIUM CHLORIDE
Positive reaction for Lauryl Tryptose Broth
Fermentation (Gas, Yellowing, Turbidity)
How much sample per tube in PRESUMPTIVE TEST and How long to incubate
10ml per tube
24-48 Hours
BRILLIANT GREEN BILE LACTOSE BROTH
- Nitrogen & Carbon Source
- Carb Source
- Noncoliforms Inhibitor
- Fecal Streptococci Inhibitor
- PEPTONE
- LACTOSE
- BRILLIANT GREEN
- BILE SALTS
How much sample per tube in TOTAL COLIFORM CONFIRMATORY TEST and How long to incubate
2-3 Loopful per tube
35 deg C for 24-48 hours
Positive reaction for Brilliant Green Bile Lactose Broth
Gas
EC BROTH
- Nitrogen & Carbon Source
- Carb Source
- Fecal Streptococci Inhibitor
- Maintains osmosis
- Controls pH
- CASEIN
- LACTOSE
- BILE SALTS
- SODIUM CHLORIDE
- POTASSIUM PHOSPHATES
Positive reaction for EC Broth
Gas
EC-MUG BROTH
- Nitrogen & Carbon Source
- Carb Source
- Fecal Streptococci Inhibitor
- Maintains osmosis
- Controls pH
- Indicator
- CASEIN
- LACTOSE
- BILE SALTS
- SODIUM CHLORIDE
- POTASSIUM PHOSPHATES
- 4-Methylumbelliferyl B-D-Glucuronide (MUG)
Positive reaction for EC-MUG Broth
Fluorescence
How much sample per tube in FECAL COLIFORM CONFIRMATORY TEST and How long to incubate
2-3 Loopful per tube
44.5 deg C for 24 Hours
is an estimation based on statistical tables that correlate the pattern of positive and negative tubes with the most probable number of organisms
Most Probable Number
MPN/ ml Table equivalent
0= <1.1
1= 1.1
2= 2.6
3=4.6
4= 8.0
5= >8.0
Is an analytic method that is a useful operational tool for monitoring bacteriological water quality throughout the treatment process and in the distribution system
HETEROTROPHIC PLATE COUNT
how to count HPC for plates with 30- 300 colonies
CFU/ml= Colonies counted / actual volume of sample plated, mL
how to count HPC for plates with > 300 colonies
count to nearest 300 and compute CFU, report as ECFU/ ml
how to count HPC for plates with 10 colonies per square (Glass Plate)
Count 13 Squares (7 Horizontal, 6 Vertical) then multiply by 5
